Nature , IF:49.962 , 2023 Jan , V613 (7942) : P145-152 doi: 10.1038/s41586-022-05529-9
NLR surveillance of pathogen interference with hormone receptors induces immunity.
Key Laboratory of Plant Immunity, Department of Plant Pathology, Nanjing Agricultural University, Nanjing, China.; Howard Hughes Medical Institute, Department of Biology, Duke University, Durham, NC, USA.; Department of Plant Biology and The Genome Center, College of Biological Sciences, University of California, Davis, CA, USA.; Key Laboratory of Plant Immunity, Department of Plant Pathology, Nanjing Agricultural University, Nanjing, China. taoxiaorong@njau.edu.cn.
Phytohormone signalling pathways have an important role in defence against pathogens mediated by cell-surface pattern recognition receptors and intracellular nucleotide-binding leucine-rich repeat class immune receptors(1,2) (NLR). Pathogens have evolved counter-defence strategies to manipulate phytohormone signalling pathways to dampen immunity and promote virulence(3). However, little is known about the surveillance of pathogen interference of phytohormone signalling by the plant innate immune system. The pepper (Capsicum chinense) NLR Tsw, which recognizes the effector nonstructural protein NSs encoded by tomato spotted wilt orthotospovirus (TSWV), contains an unusually large leucine-rich repeat (LRR) domain. Structural modelling predicts similarity between the LRR domain of Tsw and those of the jasmonic acid receptor COI1, the auxin receptor TIR1 and the strigolactone receptor partner MAX2. This suggested that NSs could directly target hormone receptor signalling to promote infection, and that Tsw has evolved a LRR resembling those of phytohormone receptors LRR to induce immunity. Here we show that NSs associates with COI1, TIR1 and MAX2 through a common repressor-TCP21-which interacts directly with these phytohormone receptors. NSs enhances the interaction of COI1, TIR1 or MAX2 with TCP21 and blocks the degradation of corresponding transcriptional repressors to disable phytohormone-mediated host immunity to the virus. Tsw also interacts directly with TCP21 and this interaction is enhanced by viral NSs. Downregulation of TCP21 compromised Tsw-mediated defence against TSWV. Together, our findings reveal that a pathogen effector targets TCP21 to inhibit phytohormone receptor function, promoting virulence, and a plant NLR protein has evolved to recognize this interference as a counter-virulence strategy, thereby activating immunity.
PMID: 36517600
Trends Plant Sci , IF:18.313 , 2023 Feb doi: 10.1016/j.tplants.2023.02.003
The consequences of synthetic auxin herbicide on plant-herbivore interactions.
Department of Ecology and Evolutionary Biology, University of Michigan, Ann Arbor, MI 48109, USA.; Department of Ecology and Evolutionary Biology, University of Michigan, Ann Arbor, MI 48109, USA. Electronic address: rsbaucom@umich.edu.
Although herbicide drift is a common side effect of herbicide application in agroecosystems, its effects on the ecology and evolution of natural communities are rarely studied. A recent shift to dicamba, a synthetic auxin herbicide known for 'drifting' to nontarget areas, necessitates the examination of drift effects on the plant-insect interactions that drive eco-evo dynamics in weed communities. We review current knowledge of direct effects of synthetic auxin herbicides on plant-insect interactions, focusing on plant herbivory, and discuss potential indirect effects, which are cascading effects on organisms that interact with herbicide-exposed plants. We end by developing a framework for the study of plant-insect interactions given drift, highlighting potential changes to plant developmental timing, resource quantity, quality, and cues.
PMID: 36842859
Trends Plant Sci , IF:18.313 , 2023 Jan doi: 10.1016/j.tplants.2022.12.004
Auxin-cytokinin interplay shapes root functionality under low-temperature stress.
Department of Agronomy, Kansas State University, Manhattan, KA 66506, USA. Electronic address: manishtiwari@ksu.edu.; Department of Agronomy, Kansas State University, Manhattan, KA 66506, USA.; Department of Agronomy, Horticulture, and Plant Science, South Dakota State University, Brookings, SD 57006, USA.; Department of Molecular and Structural Biochemistry, North Carolina State University, Raleigh, NC 27695, USA.; Department of Agronomy, Kansas State University, Manhattan, KA 66506, USA; Department of Plant and Soil Science, Texas Tech University, Lubbock, TX 79410, USA. Electronic address: kjagadish.sv@ttu.edu.
Low-temperature stress alters root system architecture. In particular, changes in the levels and response to auxin and cytokinin determine the fate of root architecture and function under stress because of their vital roles in regulating root cell division, differentiation, and elongation. An intricate nexus of genes encoding components of auxin and cytokinin biosynthesis, signaling, and transport components operate to counteract stress and facilitate optimum development. We review the role of auxin transport and signaling and its regulation by cytokinin during root development and stem cell maintenance under low-temperature stress. We highlight intricate mechanisms operating in root stem cells to minimize DNA damage by altering phytohormone levels, and discuss a working model for cytokinin in low-temperatures stress response.
PMID: 36599768
Trends Plant Sci , IF:18.313 , 2023 Feb , V28 (2) : P131-134 doi: 10.1016/j.tplants.2022.10.007
Growth or stress responses: TMK-FER balancing act.
State Key Laboratory of Crop Biology, Engineering Center of Saline-Alkali Soil Plant - Microbial Joint Restoration, Shandong Agricultural University, Tai'an 271018, China.; State Key Laboratory of Crop Biology, Engineering Center of Saline-Alkali Soil Plant - Microbial Joint Restoration, Shandong Agricultural University, Tai'an 271018, China. Electronic address: shizhong@sdau.edu.cn.; State Key Laboratory of Crop Biology, Engineering Center of Saline-Alkali Soil Plant - Microbial Joint Restoration, Shandong Agricultural University, Tai'an 271018, China. Electronic address: cczheng@sdau.edu.cn.
Transmembrane kinases (TMKs) and Feronia (FER) belong to the leucine-rich repeat receptor-like kinase family. Recent studies reveal that they coordinate plant growth and stress responses by regulating the balance between acidification and alkalization and crosstalk between auxin and abscisic acid, revealing a dynamic equilibrium in the regulation of the TMK-FER module in plants.
PMID: 36371397
Trends Plant Sci , IF:18.313 , 2023 Jan , V28 (1) : P54-73 doi: 10.1016/j.tplants.2022.08.019
Is auxin enough? Cytokinins and margin patterning in simple leaves.
Instituto de Bioingenieria, Universidad Miguel Hernandez, Campus de Elche, 03202 Elche, Alicante, Spain.; Instituto de Bioingenieria, Universidad Miguel Hernandez, Campus de Elche, 03202 Elche, Alicante, Spain. Electronic address: jlmicol@umh.es.
The interplay between auxin and cytokinins affects facets of plant development as different as ovule formation and lateral root initiation. Moreover, cytokinins favor complexity in the development of Solanum lycopersicum and Cardamine hirsuta compound leaves. Nevertheless, no role has been proposed for cytokinins in patterning the margins of the simple leaves of Arabidopsis thaliana, a process that is assumed to be sufficiently explained by auxin localization. Here, we discuss evidence supporting the hypothesis that cytokinins play a role in simple leaf margin morphogenesis via crosstalk with auxin, as occurs in other plant developmental events. Indeed, mutant or transgenic arabidopsis plants defective in cytokinin biosynthesis or signaling, or with increased cytokinin degradation have leaf margins less serrated than the wild type.
PMID: 36180378
Nat Commun , IF:14.919 , 2023 Jan , V14 (1) : P423 doi: 10.1038/s41467-023-36200-0
A phosphoinositide hub connects CLE peptide signaling and polar auxin efflux regulation.
Department of Plant Molecular Biology, University of Lausanne, CH-1015, Lausanne, Switzerland.; Institute of Plant and Microbial Biology, University of Zurich, Zurich-Basel Plant Science Center, CH-8008, Zurich, Switzerland.; Department of Biology, Western University, London, Canada.; Department of Plant Molecular Biology, University of Lausanne, CH-1015, Lausanne, Switzerland. christian.hardtke@unil.ch.
Auxin efflux through plasma-membrane-integral PIN-FORMED (PIN) carriers is essential for plant tissue organization and tightly regulated. For instance, a molecular rheostat critically controls PIN-mediated auxin transport in developing protophloem sieve elements of Arabidopsis roots. Plasma-membrane-association of the rheostat proteins, BREVIS RADIX (BRX) and PROTEIN KINASE ASSOCIATED WITH BRX (PAX), is reinforced by interaction with PHOSPHATIDYLINOSITOL-4-PHOSPHATE-5-KINASE (PIP5K). Genetic evidence suggests that BRX dampens autocrine signaling of CLAVATA3/EMBRYO SURROUNDING REGION-RELATED 45 (CLE45) peptide via its receptor BARELY ANY MERISTEM 3 (BAM3). How excess CLE45-BAM3 signaling interferes with protophloem development and whether it does so directly or indirectly remains unclear. Here we show that rheostat polarity is independent of PIN polarity, but interdependent with PIP5K. Catalytically inactive PIP5K confers rheostat polarity without reinforcing its localization, revealing a possible PIP5K scaffolding function. Moreover, PIP5K and PAX cooperatively control local PIN abundance. We further find that CLE45-BAM3 signaling branches via RLCK-VII/PBS1-LIKE (PBL) cytoplasmic kinases to destabilize rheostat localization. Our data thus reveal antagonism between CLE45-BAM3-PBL signaling and PIP5K that converges on auxin efflux regulation through dynamic control of PAX polarity. Because second-site bam3 mutation suppresses root as well as shoot phenotypes of pip5k mutants, CLE peptide signaling likely modulates phosphoinositide-dependent processes in various developmental contexts.
PMID: 36702874
Sci Adv , IF:14.136 , 2023 Jan , V9 (1) : Peade2493 doi: 10.1126/sciadv.ade2493
Auxin promotes hypocotyl elongation by enhancing BZR1 nuclear accumulation in Arabidopsis.
The Key Laboratory of Plant Development and Environmental Adaptation Biology, Ministry of Education, School of Life Sciences, Shandong University, Qingdao, Shandong, China.
Auxin and brassinosteroids (BRs) are two major growth-promoting phytohormones that shape hypocotyl elongation; however, the cross-talk between auxin and BR in this process is not fully understood. In this study, we found that auxin-induced hypocotyl elongation is dependent on brassinazole-resistant 1 (BZR1), a core BR signaling component. Auxin promotes BZR1 nuclear accumulation in hypocotyl cells, a process dependent on mitogen-activated protein kinase 3 (MPK3) and MPK6, which are both activated by auxin and whose encoding genes are highly expressed in hypocotyls. We determined that MPK3/MPK6 phosphorylate and reduce the protein stability of general regulatory factor 4 (GRF4), a member of the 14-3-3 family of proteins that retain BZR1 in the cytoplasm. In summary, this study reveals the molecular mechanism by which auxin promotes hypocotyl elongation by enhancing BZR1 nuclear accumulation via MPK3/MPK6-regulated GRF4 protein stability.
PMID: 36598987
Mol Plant , IF:13.164 , 2023 Jan doi: 10.1016/j.molp.2023.01.010
Ca(2+)-dependent TaCCD1 cooperates with TaSAUR215 to enhance plasma membrane H(+)-ATPase activity and alkali stress tolerance by inhibiting PP2C-mediated dephosphorylation of TaHA2 in wheat.
Key Laboratory of Plant Development and Environmental Adaptation Biology, Ministry of Education, School of Life Science, Shandong University, Qingdao 266237, China.; Key Laboratory of Plant Development and Environmental Adaptation Biology, Ministry of Education, School of Life Science, Shandong University, Qingdao 266237, China. Electronic address: lshuwei@sdu.edu.cn.
Alkali stress is a major constraint for crop production in large regions of saline-alkali land. However, little is known about the mechanisms through which wheat responds to alkali stress. In this study, we identified a calcium ion-binding protein from wheat, TaCCD1, which is critical for regulating the plasma membrane (PM) H(+)-ATPase-mediated alkali stress response. Plasma membrane H(+)-ATPase activity is closely related to alkali tolerance in the wheat variety Shanrong 4 (SR4). We found that two D-clade type 2C protein phosphatases, TaPP2C.D1 and TaPP2C.D8 (TaPP2C.D1/8), negatively modulated alkali stress tolerance by inhibiting PM H(+)-ATPase activity via dephosphorylating the penultimate threonine residue (Thr926) of TaHA2. Alkali stress induced the expression of TaCCD1 in SR4, and TaCCD1 interacted with TaSAUR215, an early auxin-responsive protein. These responses were both dependent on calcium signaling triggered by alkali stress. TaCCD1 enhanced the inhibitory effect of TaSAUR215 on TaPP2C.D1/8 activity, thereby promoting the activity of the PM H(+)-ATPase TaHA2 and alkali stress tolerance in wheat. Functional and genetic analyses verified the effects of these genes in response to alkali stress and indicated that TaPP2C.D1/8 are located downstream of TaSAUR215 and TaCCD1. In conclusion, this study describes a comprehensive signaling pathway for the regulation of wheat responses to alkali stress. In this pathway, Ca(2+)-dependent TaCCD1 cooperates with TaSAUR215 to enhance PM H(+)-ATPase activity and alkali stress tolerance by inhibiting the TaPP2C.D1/8-mediated dephosphorylation of the penultimate threonine residue of PM H(+)-ATPase TaHA2 in wheat.
PMID: 36681864
Mol Plant , IF:13.164 , 2023 Feb , V16 (2) : P322-336 doi: 10.1016/j.molp.2022.12.013
Natural variations of OsAUX5, a target gene of OsWRKY78, control the neutral essential amino acid content in rice grains.
Sanya Nanfan Research Institute of Hainan University, Hainan Yazhou Bay Seed Laboratory, Sanya 572025, China; College of Tropical Crops, Hainan University, Haikou 570228, China.; Max Planck Institute of Molecular Plant Physiology, 14476 Potsdam-Golm, Germany.; National Key Laboratory of Crop Genetic Improvement and National Center of Plant Gene Research (Wuhan), Huazhong Agricultural University, Wuhan 430070, China.; Sanya Nanfan Research Institute of Hainan University, Hainan Yazhou Bay Seed Laboratory, Sanya 572025, China; College of Tropical Crops, Hainan University, Haikou 570228, China. Electronic address: jincheng@hainanu.edu.cn.; Sanya Nanfan Research Institute of Hainan University, Hainan Yazhou Bay Seed Laboratory, Sanya 572025, China; College of Tropical Crops, Hainan University, Haikou 570228, China. Electronic address: jie.luo@hainanu.edu.cn.
Grain essential amino acid (EAA) levels contribute to rice nutritional quality. However, the molecular mechanisms underlying EAA accumulation and natural variation in rice grains remain unclear. Here we report the identification of a previously unrecognized auxin influx carrier subfamily gene, OsAUX5, which encodes an amino acid transporter that functions in uptake of multiple amino acids. We identified an elite haplotype of Pro::OsAUX5(Hap2) that enhances grain EAA accumulation without an apparent negative effect on agronomic traits. Natural variations of OsAUX5 occur in the cis elements of its promoter, which are differentially activated because of the different binding affinity between OsWRKY78 and the W-box, contributing to grain EAA variation among rice varieties. The two distinct haplotypes were shown to have originated from different Oryza rufipogon progenitors, which contributed to the divergence between japonica and indica. Introduction of the indica-type Pro::OsAUX5(Hap2) genotype into japonica could significantly increase EAA levels, indicating that indica-type Pro::OsAUX5(Hap2) can be utilized to increase grain EAAs of japonica varieties. Collectively, our study uncovers an WRKY78-OsAUX5-based regulatory mechanism controlling grain EAA accumulation and provides a potential target for breeding EAA-rich rice.
PMID: 36540024
Mol Plant , IF:13.164 , 2023 Jan , V16 (1) : P260-278 doi: 10.1016/j.molp.2022.09.004
The protein-protein interaction landscape of transcription factors during gynoecium development in Arabidopsis.
Unidad de Genomica Avanzada (UGA-LANGEBIO), Centro de Investigacion y de Estudios Avanzados del Instituto Politecnico Nacional (CINVESTAV-IPN), Irapuato, Guanajuato 36824, Mexico.; Departamento de Biotecnologia y Bioquimica, Unidad Irapuato, CINVESTAV-IPN, Irapuato, Guanajuato 36824, Mexico.; Instituto de Fisica, Universidad de San Luis Potosi, San Luis Potosi, SLP 78290, Mexico.; Unidad de Genomica Avanzada (UGA-LANGEBIO), Centro de Investigacion y de Estudios Avanzados del Instituto Politecnico Nacional (CINVESTAV-IPN), Irapuato, Guanajuato 36824, Mexico. Electronic address: stefan.defolter@cinvestav.mx.
Flowers are composed of organs whose identity is defined by the combinatorial activity of transcription factors (TFs). The interactions between MADS-box TFs and protein complex formation have been schematized in the floral quartet model of flower development. The gynoecium is the flower's female reproductive part, crucial for fruit and seed production and, hence, for reproductive success. After the establishment of carpel identity, many tissues arise to form a mature gynoecium. TFs have been described as regulators of gynoecium development, and some interactions and complexes have been identified. However, broad knowledge about the interactions among these TFs and their participation during development remains scarce. In this study, we used a systems biology approach to understand the formation of a complex reproductive unit-as the gynoecium-by mapping binary interactions between well-characterized TFs. We analyzed almost 4500 combinations and detected more than 250 protein-protein interactions (PPIs), resulting in a process-specific interaction map. Topological analyses suggest hidden functions and novel roles for many TFs. In addition, we observed a close relationship between TFs involved in auxin and cytokinin-signaling pathways and other TFs. Furthermore, we analyzed the network by combining PPI data, expression, and genetic data, which helped us to dissect it into several dynamic spatio-temporal subnetworks related to gynoecium development processes. Finally, we generated an extended PPI network that predicts new players in gynoecium development. Taken together, all these results serve as a valuable resource for the plant community.
PMID: 36088536
EMBO J , IF:11.598 , 2023 Feb : Pe113018 doi: 10.15252/embj.2022113018
The birth of a giant: evolutionary insights into the origin of auxin responses in plants.
Laboratory of Biochemistry, Wageningen University, Wageningen, the Netherlands.
The plant signaling molecule auxin is present in multiple kingdoms of life. Since its discovery, a century of research has been focused on its action as a phytohormone. In land plants, auxin regulates growth and development through transcriptional and non-transcriptional programs. Some of the molecular mechanisms underlying these responses are well understood, mainly in Arabidopsis. Recently, the availability of genomic and transcriptomic data of green lineages, together with phylogenetic inference, has provided the basis to reconstruct the evolutionary history of some components involved in auxin biology. In this review, we follow the evolutionary trajectory that allowed auxin to become the "giant" of plant biology by focusing on bryophytes and streptophyte algae. We consider auxin biosynthesis, transport, physiological, and molecular responses, as well as evidence supporting the role of auxin as a chemical messenger for communication within ecosystems. Finally, we emphasize that functional validation of predicted orthologs will shed light on the conserved properties of auxin biology among streptophytes.
PMID: 36786017
Plant Cell , IF:11.277 , 2023 Jan doi: 10.1093/plcell/koad012
Hormone synergy: Auxin and jasmonate boost abscisic acid signaling via ARF10 and ARF16.
Assistant Features Editor, The Plant Cell, American Society of Plant Biologists, USA.; Department of Cell and Developmental Biology, University of California San Diego, La Jolla, 92093, USA.
PMID: 36651138
Plant Cell , IF:11.277 , 2023 Jan doi: 10.1093/plcell/koad004
Gateway to morphogenesis: TIR1 auxin receptor is essential for cellular differentiation and organ formation in Marchantia polymorpha.
Assistant Features Editor, The Plant Cell, American Society of Plant Biologists, USA.; Laboratory of Biochemistry, Wageningen University and Research, Wageningen, the Netherlands.
PMID: 36648106
Plant Cell , IF:11.277 , 2023 Feb , V35 (2) : P738-755 doi: 10.1093/plcell/koac335
Natural variation in CRABS CLAW contributes to fruit length divergence in cucumber.
State Key Laboratories of Agrobiotechnology, Beijing Key Laboratory of Growth and Developmental Regulation for Protected Vegetable Crops, MOE Joint Laboratory for International Cooperation in Crop Molecular Breeding, China Agricultural University, Beijing 100193, China.; School of Life Science, Key Laboratory of Herbage & Endemic Crop Biology, Ministry of Education, Inner Mongolia University, Hohhot 010070, China.; Horticulture Department, University of Wisconsin-Madison, 1575 Linden Drive, Madison, Wisconsin 53706, USA.; College of Horticulture, Hunan Agricultural University, Changsha, China.; USDA-ARS, Vegetable Crops Research Unit, 1575 Linden Drive, Madison, Wisconsin 53706, USA.
Fruit length is a key domestication trait that affects crop yield and appearance. Cucumber (Cucumis sativus) fruits vary from 5 to 60 cm in length. Despite the identification of several regulators and multiple quantitative trait loci (QTLs) underlying fruit length, the natural variation, and molecular mechanisms underlying differences in fruit length are poorly understood. Through map-based cloning, we identified a nonsynonymous polymorphism (G to A) in CRABS CLAW (CsCRC) as underlying the major-effect fruit size/shape QTL FS5.2 in cucumber. The short-fruit allele CsCRCA is a rare allele that has only been found in round-fruited semi-wild Xishuangbanna cucumbers. A near-isogenic line (NIL) homozygous for CsCRCA exhibited a 34 approximately 39% reduction in fruit length. Introducing CsCRCG into this NIL rescued the short-fruit phenotype, and knockdown of CsCRCG resulted in shorter fruit and smaller cells. In natural cucumber populations, CsCRCG expression was positively correlated with fruit length. Further, CsCRCG, but not CsCRCA, targets the downstream auxin-responsive protein gene CsARP1 to regulate its expression. Knockout of CsARP1 produced shorter fruit with smaller cells. Hence, our work suggests that CsCRCG positively regulates fruit elongation through transcriptional activation of CsARP1 and thus enhances cell expansion. Using different CsCRC alleles provides a strategy to manipulate fruit length in cucumber breeding.
PMID: 36427253
Plant Cell , IF:11.277 , 2023 Jan , V35 (1) : P390-408 doi: 10.1093/plcell/koac316
Brassinosteroids promote etiolated apical structures in darkness by amplifying the ethylene response via the EBF-EIN3/PIF3 circuit.
School of Life Sciences, Southwest University, Chongqing 400715, China.; State Key Laboratory of Protein and Plant Gene Research, School of Advanced Agricultural Sciences and Life Sciences, Peking University, Beijing 100871, China.; Peking-Tsinghua Center for Life Sciences, Academy for Advanced Interdisciplinary Studies, Peking University, Beijing 100871, China.; Key Laboratory of Growth Regulation and Transformation Research of Zhejiang Province, School of Life Sciences, Westlake University, 18 Shilongshan Road, Hangzhou 310024, China.; Key Laboratory of Molecular Design for Plant Cell Factory of Guangdong Higher Education Institutes, Institute of Plant and Food Science, School of Life Sciences, Southern University of Science and Technology, Shenzhen 518055, China.
Germinated plants grow in darkness until they emerge above the soil. To help the seedling penetrate the soil, most dicot seedlings develop an etiolated apical structure consisting of an apical hook and folded, unexpanded cotyledons atop a rapidly elongating hypocotyl. Brassinosteroids (BRs) are necessary for etiolated apical development, but their precise role and mechanisms remain unclear. Arabidopsis thaliana SMALL AUXIN UP RNA17 (SAUR17) is an apical-organ-specific regulator that promotes production of an apical hook and closed cotyledons. In darkness, ethylene and BRs stimulate SAUR17 expression by transcription factor complexes containing PHYTOCHROME-INTERACTING FACTORs (PIFs), ETHYLENE INSENSITIVE 3 (EIN3), and its homolog EIN3-LIKE 1 (EIL1), and BRASSINAZOLE RESISTANT1 (BZR1). BZR1 requires EIN3 and PIFs for enhanced DNA-binding and transcriptional activation of the SAUR17 promoter; while EIN3, PIF3, and PIF4 stability depends on BR signaling. BZR1 transcriptionally downregulates EIN3-BINDING F-BOX 1 and 2 (EBF1 and EBF2), which encode ubiquitin ligases mediating EIN3 and PIF3 protein degradation. By modulating the EBF-EIN3/PIF protein-stability circuit, BRs induce EIN3 and PIF3 accumulation, which underlies BR-responsive expression of SAUR17 and HOOKLESS1 and ultimately apical hook development. We suggest that in the etiolated development of apical structures, BRs primarily modulate plant sensitivity to darkness and ethylene.
PMID: 36321994
Plant Cell , IF:11.277 , 2023 Jan , V35 (1) : P453-468 doi: 10.1093/plcell/koac297
The RAC/ROP GTPase activator OsRopGEF10 functions in crown root development by regulating cytokinin signaling in rice.
State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, South China Agricultural University, Guangzhou 510642, China.; Guangdong Provincial Key Laboratory of Protein Function and Regulation in Agricultural Organisms, College of Life Sciences, South China Agricultural University, Guangzhou 510642, China.; Guangdong Laboratory for Lingnan Modern Agriculture, Guangzhou 510642, China.; Department of Biochemistry and Molecular Biology, University of Massachusetts, Amherst, Massachusetts 01003, USA.
RAC/Rho of plant (ROP) GTPases are major molecular switches that control diverse signaling cascades for plant growth, development, and defense. Here, we discovered a signaling node that connects RAC/ROPs to cytokinins. Rice (Oryza sativa) plants develop a fibrous root system mainly composed of crown roots. Cytokinin signaling via a phosphorelay system is critical for crown root development. We show that OsRopGEF10, which activates RAC/ROPs, acts upstream of the cytoplasmic-nuclear shuttling phosphotransfer proteins AHPs of the cytokinin signaling pathway to promote crown root development. Mutations of OsRopGEF10 induced hypersensitivity to cytokinin, whereas overexpressing this gene reduced the cytokinin response. Loss of OsRopGEF10 function reduced the expression of the response regulator gene OsRR6, a repressor of cytokinin signaling, and impaired crown root development. Mutations in OsAHP1/2 led to increased crown root production and rescued the crown root defect of Osropgef10. Furthermore, auxin activates the ROP GTPase OsRAC3, which attenuates cytokinin signaling for crown root initiation. Molecular interactions between OsRopGEF10, OsRAC3, and OsAHP1/2 implicate a mechanism whereby OsRopGEF10-activated OsRAC3 recruits OsAHP1/2 to the cortical cytoplasm, sequestering them from their phosphorelay function in the nucleus. Together, our findings uncover the OsRopGEF10-OsRAC3-OsAHP1/2 signaling module, establish a link between RAC/ROPs and cytokinin, and reveal molecular crosstalk between auxin and cytokinin during crown root development.
PMID: 36190337
Proc Natl Acad Sci U S A , IF:11.205 , 2023 Jan , V120 (3) : Pe2209781120 doi: 10.1073/pnas.2209781120
CPR5-mediated nucleo-cytoplasmic localization of IAA12 and IAA19 controls lateral root development during abiotic stress.
Department of Life Sciences, Pohang University of Science and Technology, Pohang 37673, Korea.; Department of Systems Biology, Yonsei University, Seoul 03722, Korea.; Institute for Convergence Research and Education in Advanced Technology, Yonsei University, Incheon 21983, Korea.
Plasticity of the root system architecture (RSA) is essential in enabling plants to cope with various environmental stresses and is mainly controlled by the phytohormone auxin. Lateral root development is a major determinant of RSA. Abiotic stresses reduce auxin signaling output, inhibiting lateral root development; however, how abiotic stress translates into a lower auxin signaling output is not fully understood. Here, we show that the nucleo-cytoplasmic distribution of the negative regulators of auxin signaling AUXIN/INDOLE-3-ACETIC ACID INDUCIBLE 12 (AUX/IAA12 or IAA12) and IAA19 determines lateral root development under various abiotic stress conditions. The cytoplasmic localization of IAA12 and IAA19 in the root elongation zone enforces auxin signaling output, allowing lateral root development. Among components of the nuclear pore complex, we show that CONSTITUTIVE EXPRESSOR OF PATHOGENESIS-RELATED GENES 5 (CPR5) selectively mediates the cytoplasmic translocation of IAA12/19. Under abiotic stress conditions, CPR5 expression is strongly decreased, resulting in the accumulation of nucleus-localized IAA12/19 in the root elongation zone and the suppression of lateral root development, which is reiterated in the cpr5 mutant. This study reveals a regulatory mechanism for auxin signaling whereby the spatial distribution of AUX/IAA regulators is critical for lateral root development, especially in fluctuating environmental conditions.
PMID: 36623191
Curr Biol , IF:10.834 , 2023 Feb , V33 (3) : PR114-R117 doi: 10.1016/j.cub.2022.12.007
Plant physiology: The to-and-fro of hormone signals to respond to drought.
Department of Biology, Duke University, Durham, NC 27708, USA.; Department of Biology, Duke University, Durham, NC 27708, USA; Howard Hughes Medical Institute, Duke University, Durham, NC 27708, USA. Electronic address: philip.benfey@duke.edu.
Xerobranching, a temporary suppression of root branching when water is limiting, is controlled by the plant hormone abscisic acid (ABA). A recently published study reveals how root branching is dynamically controlled by redistribution in opposite directions of ABA and auxin.
PMID: 36750024
Curr Biol , IF:10.834 , 2023 Jan , V33 (1) : P75-85.e5 doi: 10.1016/j.cub.2022.11.045
Local light signaling at the leaf tip drives remote differential petiole growth through auxin-gibberellin dynamics.
Plant-Environment Signaling, Department of Biology, Utrecht University, Padualaan 8, 3584 CH Utrecht, the Netherlands.; Theoretical Biology and Bioinformatics, Department of Biology, Utrecht University, Padualaan 8, 3584 CH Utrecht, the Netherlands.; Plant-Environment Signaling, Department of Biology, Utrecht University, Padualaan 8, 3584 CH Utrecht, the Netherlands; Laboratory of Biochemistry, Wageningen University, Stippeneng 4, 6708 WE Wageningen, the Netherlands.; Laboratory for Molecular Biology, Wageningen University, Droevendaalsesteeg 1, 6708 PB Wageningen, the Netherlands.; Laboratory of Biochemistry, Wageningen University, Stippeneng 4, 6708 WE Wageningen, the Netherlands.; Plant-Environment Signaling, Department of Biology, Utrecht University, Padualaan 8, 3584 CH Utrecht, the Netherlands. Electronic address: r.pierik@uu.nl.
Although plants are immobile, many of their organs are flexible to move in response to environmental cues. In dense vegetation, plants detect neighbors through far-red light perception with their leaf tip. They respond remotely, with asymmetrical growth between the abaxial and adaxial sides of the leafstalk, the petiole. This results in upward movement that brings the leaf blades into better lit zones of the canopy. The plant hormone auxin is required for this response, but it is not understood how non-differential leaf tip-derived auxin can remotely regulate movement. Here, we show that remote signaling of far-red light promotes auxin accumulation in the abaxial petiole. This local auxin accumulation is facilitated by reinforcing an intrinsic directionality of the auxin transport protein PIN3 on the petiole endodermis, as visualized with a PIN3-GFP line. Using an auxin biosensor, we show that auxin accumulates in all cell layers from endodermis to epidermis in the abaxial petiole, upon far-red light signaling in the remote leaf tip. In the petiole, auxin elicits a response to both auxin itself as well as a second growth promoter; gibberellin. We show that this dual regulation is necessary for hyponastic leaf movement in response to light. Our data indicate that gibberellin is required to permit cell growth, whereas differential auxin accumulation determines which cells can grow. Our results reveal how plants can spatially relay information about neighbor proximity from their sensory leaf tips to the petiole base, thus driving adaptive growth.
PMID: 36538931
J Hazard Mater , IF:10.588 , 2023 Mar , V445 : P130530 doi: 10.1016/j.jhazmat.2022.130530
Pre treatment of melatonin rescues cotton seedlings from cadmium toxicity by regulating key physio-biochemical and molecular pathways.
State Key Laboratory of Grassland Agro-ecosystems, College of Ecology, Lanzhou University, Lanzhou 730000, China; School of Life Science and Technology, Henan Institute of Science and Technology, Hualan St. 90, Xinxiang 453003, China.; State Key Laboratory of Cotton Biology, Institute of Cotton Research of Chinese Academy of Agricultural Sciences, Anyang 450000, China; Hainan Yazhou Bay Seed Laboratory, Sanya 572024, China; National Nanfan Research Institute (Sanya), Chinese Academy of Agriculture Sciences, Sanya 572024, China.; School of Life Science and Technology, Henan Institute of Science and Technology, Hualan St. 90, Xinxiang 453003, China.; Faculty of Science, University Brunei Darussalam, Jalan Tungku Link, Gadong BE1410, Brunei Darussalam.; Institute of Ecology and Evolution, 5289 University of Oregon, Eugene, OR 97403, USA.; Sinopharm Wuhan Plasma-derived Biotherapies Co., Ltd, Wuhan, China.; School of Life Science and Technology, Henan Institute of Science and Technology, Hualan St. 90, Xinxiang 453003, China. Electronic address: ruiyangzh@gmail.com.; State Key Laboratory of Grassland Agro-ecosystems, College of Ecology, Lanzhou University, Lanzhou 730000, China. Electronic address: xiongyc@lzu.edu.cn.
Melatonin, a plant/animal origin hormone, regulates plant response to abiotic stresses by protecting them from oxidative damage. This study identified physiochemical and molecular mechanism of melatonin-induced cadmium (Cd) stress tolerance and detoxification in cotton seedlings. Cotton seedlings, with or without melatonin (15 microM) pretreatment, were subjected to Cd (100 microM) stress in a hydroponic medium for eight days. We found that higher cellular Cd accumulation in leaf tissues significantly inhibited the growth and physiology of cotton seedlings. In contrast, melatonin-treated seedlings maintained leaf photosynthetic capacity, producing relatively higher fresh (17.4%) and dry (19.3%) weights than non-melatonin-treated plants under Cd-contaminated environments. The improved growth and leaf functioning were strongly linked with the melatonin-induced repression of Cd transporter genes (LOC107894197, LOC107955631, LOC107899273) in roots. Thus, melatonin induced downregulation of the Cd transporter genes further inhibited Cd ion transport towards leaf tissues. This suggests that the differentially expressed transporter genes (DEG) are key drivers of the melatonin-mediated regulation of Cd transportation and sequestration in cotton. Melatonin also protected cotton seedlings from Cd-induced oxidative injury by reducing tissues malondialdehyde (MDA) and hydrogen peroxide (H(2)O(2)) levels and increasing the activities of superoxide dismutase (SOD), peroxidase (POD), catalase (CAT), and ascorbate peroxidase (APX) enzymes. Transcriptomic analysis revealed that melatonin activated mitogen-activated protein kinase (MAPK) signaling pathways to simulate stomatal adjustment and photosynthesis in Cd-stressed leaves. Further, melatonin protects intercellular organs, particularly ribosomes, from Cd-induced oxidative damage by promoting ribosomal biosynthesis and improving translational efficiency. The findings elucidated the molecular basis of melatonin-mediated Cd stress tolerance in plants and provided a key for the effective strategy of Cd accumulation in cotton.
PMID: 36463746
J Hazard Mater , IF:10.588 , 2023 Feb , V444 (Pt A) : P130427 doi: 10.1016/j.jhazmat.2022.130427
Transcriptome reveals the exposure effects of CeO(2) nanoparticles on pakchoi (Brassica chinensis L.) photosynthesis.
College of Environment, Zhejiang University of Technology, Hangzhou, Zhejiang 310014, China. Electronic address: jhong@zjut.edu.cn.; College of Environment, Zhejiang University of Technology, Hangzhou, Zhejiang 310014, China.; College of Life Sciences, Shanxi Agricultural University, Taigu, Shanxi 030801, China.; Department of Chemistry and Biochemistry, The University of Texas, El Paso, TX 79968, United States.
In this study, soil-grown pakchoi after 2 weeks seedling cultivation were exposed to CeO(2) nanoparticles (CeO(2) NPs) at 0.7, 7, 70, and 350 mg kg(-1) for 30 days. Results showed that chlorophyll content and photosynthetic assimilation rate were decreased significantly under all treatments with the largest decrease of 34.16% (0.7 mg kg(-1) CeO(2) NPs), however, sub-stomatal CO(2) was increased dramatically under low dose of CeO(2) NPs (0.7 mg kg(-1)). There were 4576, 3548, 2787, and 2514 genes up/down regulated significantly by 0.7, 7, 70, and 350 mg kg(-1) CeO(2) NPs, respectively, and 767 genes affected under all treatments. In addition, 0.7 mg kg(-1) CeO(2) NPs up-regulated 10 chlorophyll synthesis genes, 20 photosynthesis genes, and 10 carbon fixation enzyme genes; while 350 mg kg(-1) CeO(2) NPs down-regulated 5 photosynthesis genes and 28 auxin-activated genes. Among the key genes of photosynthesis, Ferredoxin-NADP reductase (PetH) was upregulated in 0.7, 7 and 70 mg kg(-1) treatments, while Photosystem II lipoprotein (Psb27) was downregulated under 7, 70 and 350 mg kg(-1) treatments. Top 20 metabolic pathways affected by CeO(2) NPs including plant hormone, amino acids, and glutathione, and carbon metabolism These results provide information about utilizing CeO(2) NPs more safely and effectively in the future.
PMID: 36410248
J Hazard Mater , IF:10.588 , 2023 Jan , V441 : P129843 doi: 10.1016/j.jhazmat.2022.129843
Changes in the m6A RNA methylome accompany the promotion of soybean root growth by rhizobia under cadmium stress.
College of Agriculture, Northeast Agricultural University, Harbin 150030, Heilongjiang, People's Republic of China.; Daqing Branch, Heilongjiang Academy of Agricultural Sciences, Daqing 163316, Heilongjiang, People's Republic of China.; College of Agriculture, Northeast Agricultural University, Harbin 150030, Heilongjiang, People's Republic of China. Electronic address: qshchen@126.com.; College of Agriculture, Northeast Agricultural University, Harbin 150030, Heilongjiang, People's Republic of China. Electronic address: qizhaoming1860@126.com.
Cadmium (Cd) is the most widely distributed heavy metal pollutant in soil and has significant negative effects on crop yields and human health. Rhizobia can enhance soybean growth in the presence of heavy metals, and the legume-rhizobia symbiosis has been used to promote heavy-metal phytoremediation, but much remains to be learned about the molecular networks that underlie these effects. Here, we demonstrated that soybean root growth was strongly suppressed after seven days of Cd exposure but that the presence of rhizobia largely eliminated this effect, even prior to nodule development. Moreover, rhizobia did not appear to promote root growth by limiting plant Cd uptake: seedlings with and without rhizobia had similar root Cd concentrations. Previous studies have demonstrated a role for m6A RNA methylation in the response of rice and barley to Cd stress. We therefore performed transcriptome-wide m6A methylation profiling to investigate changes in the soybean RNA methylome in response to Cd with and without rhizobia. Here, we provide some of the first data on transcriptome-wide m6a RNA methylation patterns in soybean; m6A modifications were concentrated at the 3' UTR of transcripts and showed a positive relationship with transcript abundance. Transcriptome-wide m6A RNA methylation peaks increased in the presence of Cd, and the integration of m6A methylome and transcriptome results enabled us to identify 154 genes whose transcripts were both differentially methylated and differentially expressed in response to Cd stress. Annotation results suggested that these genes were associated with Ca(2+) homeostasis, ROS pathways, polyamine metabolism, MAPK signaling, hormones, and biotic stress responses. There were 176 differentially methylated and expressed transcripts under Cd stress in the presence of rhizobia. In contrast to the Cd-only gene set, they were also enriched in genes related to auxin, jasmonic acid, and brassinosteroids, as well as abiotic stress tolerance. They contained fewer genes related to Ca(2+) homeostasis and also included candidates with known functions in the legume-rhizobia symbiosis. These findings offer new insights into how rhizobia promote soybean root growth under Cd stress; they provide candidate genes for research on plant heavy metal responses and for the use of legumes in phytoremediation.
PMID: 36113351
J Nanobiotechnology , IF:10.435 , 2023 Jan , V21 (1) : P2 doi: 10.1186/s12951-022-01753-7
Silica nanoparticles promote wheat growth by mediating hormones and sugar metabolism.
MARA Key Laboratory of Sustainable Crop Production in the Middle Reaches of the Yangtze River (Co-Construction By Ministry and Province), College of Agriculture, Yangtze University, Jingzhou, 434025, Hubei, China.; Key Laboratory of Integrated Pest Management of Crops in Central China, Ministry of Agriculture/Hubei Key Laboratory of Crop Diseases, Institute of Plant Protection and Soil Science, Insect Pests and Weeds Control, Hubei Academy of Agricultural Sciences, Wuhan, 430064, Hubei, China.; MARA Key Laboratory of Sustainable Crop Production in the Middle Reaches of the Yangtze River (Co-Construction By Ministry and Province), College of Agriculture, Yangtze University, Jingzhou, 434025, Hubei, China. yinjunliang@yangtzeu.edu.cn.; MARA Key Laboratory of Sustainable Crop Production in the Middle Reaches of the Yangtze River (Co-Construction By Ministry and Province), College of Agriculture, Yangtze University, Jingzhou, 434025, Hubei, China. yongxingzhu@yangtzeu.edu.cn.
BACKGROUND: Silica nanoparticles (SiNPs) have been demonstrated to have beneficial effects on plant growth and development, especially under biotic and abiotic stresses. However, the mechanisms of SiNPs-mediated plant growth strengthening are still unclear, especially under field condition. In this study, we evaluated the effect of SiNPs on the growth and sugar and hormone metabolisms of wheat in the field. RESULTS: SiNPs increased tillers and elongated internodes by 66.7% and 27.4%, respectively, resulting in a larger biomass. SiNPs can increase the net photosynthetic rate by increasing total chlorophyll contents. We speculated that SiNPs can regulate the growth of leaves and stems, partly by regulating the metabolisms of plant hormones and soluble sugar. Specifically, SiNPs can increase auxin (IAA) and fructose contents, which can promote wheat growth directly or indirectly. Furthermore, SiNPs increased the expression levels of key pathway genes related to soluble sugars (SPS, SUS, and alpha-glucosidase), chlorophyll (CHLH, CAO, and POR), IAA (TIR1), and abscisic acid (ABA) (PYR/PYL, PP2C, SnRK2, and ABF), whereas the expression levels of genes related to CTKs (IPT) was decreased after SiNPs treatment. CONCLUSIONS: This study shows that SiNPs can promote wheat growth and provides a theoretical foundation for the application of SiNPs in field conditions.
PMID: 36593514
New Phytol , IF:10.151 , 2023 Jan doi: 10.1111/nph.18783
Save your TIRs - more to auxin than meets the eye.
John Innes Centre, Norwich, NR4 7UH, UK.; Department of Biology, University of Oxford, Oxford, OX1 3RB, UK.
Auxin has long been known as an important regulator of plant growth and development. Classical studies in auxin biology have uncovered a 'canonical' transcriptional auxin-signalling pathway involving the TRANSPORT INHIBITOR RESPONSE1/AUXIN SIGNALING F-BOX (TIR1/AFB) receptors. TIR1/AFB perception of auxin triggers the degradation of repressors and the derepression of auxin-responsive genes. Nevertheless, the canonical pathway cannot account for all aspects of auxin biology, such as physiological responses that are too rapid for transcriptional regulation. This Tansley insight will explore several 'non-canonical' pathways that have been described in recent years mediating fast auxin responses. We focus on the interplay between a nontranscriptional branch of TIR1/AFB signalling and a TRANSMEMBRANE KINASE1 (TMK1)-mediated pathway in root acid growth. Other developmental aspects involving the TMKs and their association with the controversial AUXIN-BINDING PROTEIN 1 (ABP1) will be discussed. Finally, we provide an updated overview of the ETTIN (ETT)-mediated pathway in contexts outside of gynoecium development.
PMID: 36721296
New Phytol , IF:10.151 , 2023 Jan doi: 10.1111/nph.18774
Somatic embryo initiation by rice BABY BOOM1 involves activation of zygote-expressed auxin biosynthesis genes.
Department of Plant Sciences, University of California, Davis, CA, 95616, USA.; Innovative Genomics Institute, University of California, Berkeley, CA, 94720, USA.; Department of Plant Biology, University of California, Davis, CA, 95616, USA.
Plant embryogenesis results from the fusion of male and female gametes but can also be induced in somatic cells. The molecular pathways for embryo initiation are poorly understood, especially in monocots. In rice, the male gamete expressed BABY BOOM1 (OsBBM1) transcription factor functions as an embryogenic trigger in the zygote and can also promote somatic embryogenesis when ectopically expressed in somatic tissues. We used gene editing, transcriptome profiling, and chromatin immunoprecipitation to determine the molecular players involved in embryo initiation downstream of OsBBM1. We identify OsYUCCA (OsYUC) auxin biosynthesis genes as direct targets of OsBBM1. Unexpectedly, these OsYUC targets in zygotes are expressed only from the maternal genome, whereas the paternal genome exclusively provides functional OsBBM1 to initiate embryogenesis. Induction of somatic embryogenesis by exogenous auxin requires OsBBM genes and downstream OsYUC targets. Ectopic OsBBM1 initiates somatic embryogenesis without exogenous auxins but requires functional OsYUC genes. Thus, an OsBBM-OsYUC module is a key player for both somatic and zygotic embryogenesis in rice. Zygotic embryo initiation involves a partnership of male and female genomes, through which paternal OsBBM1 activates maternal OsYUC genes. In somatic embryogenesis, exogenous auxin triggers OsBBM1 expression, which then activates endogenous auxin biosynthesis OsYUC genes.
PMID: 36707918
New Phytol , IF:10.151 , 2023 Mar , V237 (6) : P2118-2135 doi: 10.1111/nph.18691
A Physcomitrella PIN protein acts in spermatogenesis and sporophyte retention.
Plant Biotechnology, Faculty of Biology, University of Freiburg, 79104, Freiburg, Germany.; Spemann Graduate School of Biology and Medicine (SGBM), University of Freiburg, 79104, Freiburg, Germany.; CIBSS - Centre for Integrative Biological Signalling Studies, University of Freiburg, 79104, Freiburg, Germany.; Cluster of Excellence livMatS @ FIT - Freiburg Center for Interactive Materials and Bioinspired Technologies, University of Freiburg, 79110, Freiburg, Germany.
The auxin efflux PIN-FORMED (PIN) proteins are conserved in all land plants and important players in plant development. In the moss Physcomitrella (Physcomitrium patens), three canonical PINs (PpPINA-C) are expressed in the leafy shoot (gametophore). PpPINA and PpPINB show functional activity in vegetative growth and sporophyte development. Here, we examined the role of PpPINC in the life cycle of Physcomitrella. We established reporter and knockout lines for PpPINC and analysed vegetative and reproductive tissues using microscopy and transcriptomic sequencing of moss gametangia. PpPINC is expressed in immature leaves, mature gametangia and during sporophyte development. The sperm cells (spermatozoids) of pinC knockout mutants exhibit increased motility and an altered flagella phenotype. Furthermore, the pinC mutants have a higher portion of differentially expressed genes related to spermatogenesis, increased fertility and an increased abortion rate of premeiotic sporophytes. Here, we show that PpPINC is important for spermatogenesis and sporophyte retention. We propose an evolutionary conserved way of polar growth during early moss embryo development and sporophyte attachment to the gametophore while suggesting the mechanical function in sporophyte retention of a ring structure, the Lorch ring.
PMID: 36696950
New Phytol , IF:10.151 , 2023 Jan doi: 10.1111/nph.18733
Local auxin biosynthesis regulates brace root angle and lodging resistance in maize.
State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, College of Life Sciences, South China Agricultural University, Guangzhou, 510642, China.; Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Beijing, 100081, China.; HainanYazhou Bay Seed Lab, Sanya, 572025, China.; Department of Forest Sciences, Faculty of Agriculture and Forestry, University of Helsinki, Helsinki, 00790, Finland.; College of Agronomy, Qingdao Agricultural University, Qingdao, 266109, China.; Shimadzu (China) Co. Ltd Shenzhen Branch, 518042, Shenzhen, China.; Guangdong Laboratory for Lingnan Modern Agriculture, Guangzhou, 510642, China.
Root lodging poses a major threat to maize production, resulting in reduced grain yield and quality, and increased harvest costs. Here, we combined expressional, genetic, and cytological studies to demonstrate a role of ZmYUC2 and ZmYUC4 in regulating gravitropic response of the brace root and lodging resistance in maize. We show that both ZmYUC2 and ZmYUC4 are preferentially expressed in root tips with partially overlapping expression patterns, and the protein products of ZmYUC2 and ZmYUC4 are localized in the cytoplasm and endoplasmic reticulum, respectively. The Zmyuc4 single mutant and Zmyuc2/4 double mutant exhibit enlarged brace root angle compared with the wild-type plants, with larger brace root angle being observed in the Zmyuc2/4 double mutant. Consistently, the brace root tips of the Zmyuc4 single mutant and Zmyuc2/4 double mutant accumulate less auxin and are defective in proper reallocation of auxin in response to gravi-stimuli. Furthermore, we show that the Zmyuc4 single mutant and the Zmyuc2/4 double mutant display obviously enhanced root lodging resistance. Our combined results demonstrate that ZmYUC2- and ZmYUC4-mediated local auxin biosynthesis is required for normal gravity response of the brace roots and provide effective targets for breeding root lodging resistant maize cultivars.
PMID: 36636793
New Phytol , IF:10.151 , 2023 Feb , V237 (4) : P1115-1121 doi: 10.1111/nph.18602
Extranuclear auxin signaling: a new insight into auxin's versatility.
Department of Botany and Plant Sciences, Institute of Integrated Genome Biology, University of California, Riverside, CA, 92521, USA.; FAFU-UCR Joint Center for Horticultural Biology and Metabolomics, Haixia Institute of Science and Technology, Fujian Agriculture and Forestry University, Fuzhou, Fujian, 350002, China.
Auxin phytohormone has a role in most aspects of the life of a land plant and is found even in ancient plants such as single-cell green algae. Auxin's ubiquitous but specific effects have been mainly explained by the extraordinary ability of plants to interpret spatiotemporal patterns of auxin concentrations via the regulation of gene transcription. This is thought to be achieved through the combinatorial effects of two families of nuclear coreceptor proteins, that is the TRANSPORT INHIBITOR RESPONSE1 and AUXIN-SIGNALING F-BOX (TIR1/AFB) and AUXIN/INDOLE ACETIC ACID. Recent evidence has suggested transcription-independent roles of TIR1/AFBs localized outside the nucleus and TRANSMEMBRANE KINASE (TMK)-based auxin signaling occurring in the plasma membrane. Furthermore, emerging evidence supports a coordinated action of the intra- and extranuclear auxin signaling pathways to regulate specific auxin responses. Here, we highlight how auxin signaling acts inside and outside the nucleus for the regulation of growth and morphogenesis and propose that the future direction of auxin biology lies in the elucidation of a new collaborative paradigm of intra- and extranuclear auxin signaling.
PMID: 36336825
New Phytol , IF:10.151 , 2023 Feb , V237 (4) : P1320-1332 doi: 10.1111/nph.18600
Soilborne bacterium Klebsiella pneumoniae promotes cluster root formation in white lupin through ethylene mediation.
Joint International Research Laboratory of Water and Nutrient in Crop, College of Resources and Environment, Fujian Agriculture and Forestry University, Fuzhou, 350002, China.; Fujian Provincial Key Laboratory of Plant Functional Biology, College of Life Sciences, Fujian Agriculture and Forestry University, Fuzhou, 350002, China.; Department of Biology, Hong Kong Baptist University and State Key Laboratory of Agrobiotechnology, The Chinese University of Hong Kong, Shatin, Hong Kong, 999077, China.
Cluster roots of white lupin are induced by low phosphorus (LP) to efficiently access unavailable P, but how soilborne microbes are associated with cluster root formation (CRF) is unclear. We investigated the roles of soilborne bacteria in CRF response to LP by high-throughput sequencing and root-bacteria interactions. Cluster root number was significantly decreased in plants grown in sterilized soil compared with nonsterilized soil. Proteobacteria was enriched in CR, as shown by microbiome analysis of soil (bulk, rhizosphere, and rhizosheath) and roots (main, lateral, and CR). Large-scale gene expression level implicated ethylene mediation in CRF. Klebsiella pneumoniae (P7), a soilborne bacterium belonging to Proteobacteria, was isolated from CR. Among 11 isolated strains, P7 exhibited the highest 1-aminocyclopropane-1-carboxylate deaminase (ACCD) activity; this enzyme inhibits the biosynthesis of ethylene in plants by the cleavage of the ethylene precursor 1-aminocyclopropane-1-carboxylic acid and promotes CRF under LP. We constructed an ACCD-deficit mutant accd in the P7 genetic background. The loss-of-function mutation failed to promote CRF under LP conditions. Also, auxin responses may be involved in K. pneumoniae-ethylene-mediated CRF. Overall, we propose that the soilborne bacterium K. pneumoniae promotes CRF of white lupin in response to LP by ethylene mediation.
PMID: 36336781
New Phytol , IF:10.151 , 2023 Feb , V237 (4) : P1391-1404 doi: 10.1111/nph.18589
A GT-1 and PKc domain-containing transcription regulator SIMPLE LEAF1 controls compound leaf development in woodland strawberry.
Key Laboratory of Horticultural Plant Biology (Ministry of Education), Huazhong Agricultural University, Wuhan, 430070, China.; Hubei Hongshan Laboratory, Wuhan, 430070, China.; Department of Cell Biology and Molecular Genetics, University of Maryland, College Park, MD, 20742, USA.
Leaves are strikingly diverse in terms of shapes and complexity. The wild and cultivated strawberry plants mostly develop trifoliate compound leaves, yet the underlying genetic basis remains unclear in this important fruit crop in Rosaceae. Here, we identified two EMS mutants designated simple leaf1 (sl1-1 and sl1-2) and one natural simple-leafed mutant monophylla in Fragaria vesca. Their causative mutations all reside in SL1 (FvH4_7g28640) causing premature stop codon at different positions in sl1-1 and sl1-2 and an eight-nucleotide insertion (GTTCATCA) in monophylla. SL1 encodes a transcription regulator with the conserved DNA-binding domain GT-1 and the catalytic domain of protein kinases PKc. Expression of SL1pro::SL1 in sl1-1 completely restored compound leaf formation. The 35S::SL1 lines developed palmate-like leaves with four or five leaflets at a low penetrance. However, overexpressing the truncated SL1(DeltaPK) caused no phenotypes, probably due to the disruption of homodimerization. SL1 is preferentially expressed at the tips of leaflets and serrations. Moreover, SL1 is closely associated with the auxin pathway and works synergistically with FveLFYa in leaf morphogenesis. Overall, our work uncovered a new type of transcription regulator that promotes compound leaf formation in the woodland strawberry and shed new lights on the diversity of leaf complexity control.
PMID: 36319612
New Phytol , IF:10.151 , 2023 Feb , V237 (3) : P807-822 doi: 10.1111/nph.18570
Root architecture plasticity in response to endoparasitic cyst nematodes is mediated by damage signaling.
Laboratory of Nematology, Wageningen University & Research, 6708 PB, Wageningen, the Netherlands.; Laboratory of Molecular Biology, Cluster of Plant Developmental Biology, Wageningen University & Research, 6708 PB, Wageningen, the Netherlands.; State Key Laboratory of Plant Physiology and Biochemistry, College of Biological Sciences, China Agricultural University, Beijing, 100193, China.; Institute of Crop Science and Resource Conservation (INRES), Molecular Phytomedicine, University of Bonn, 53115, Bonn, Germany.
Plant root architecture plasticity in response to biotic stresses has not been thoroughly investigated. Infection by endoparasitic cyst nematodes induces root architectural changes that involve the formation of secondary roots at infection sites. However, the molecular mechanisms regulating secondary root formation in response to cyst nematode infection remain largely unknown. We first assessed whether secondary roots form in a nematode density-dependent manner by challenging wild-type Arabidopsis plants with increasing numbers of cyst nematodes (Heterodera schachtii). Next, using jasmonate-related reporter lines and knockout mutants, we tested whether tissue damage by nematodes triggers jasmonate-dependent secondary root formation. Finally, we verified whether damage-induced secondary root formation depends on local auxin biosynthesis at nematode infection sites. Intracellular host invasion by H. schachtii triggers a transient local increase in jasmonates, which activates the expression of ERF109 in a COI1-dependent manner. Knockout mutations in COI1 and ERF109 disrupt the nematode density-dependent increase in secondary roots observed in wild-type plants. Furthermore, ERF109 regulates secondary root formation upon H. schachtii infection via local auxin biosynthesis. Host invasion by H. schachtii triggers secondary root formation via the damage-induced jasmonate-dependent ERF109 pathway. This points at a novel mechanism underlying plant root plasticity in response to biotic stress.
PMID: 36285401
New Phytol , IF:10.151 , 2023 Jan , V237 (2) : P563-575 doi: 10.1111/nph.18552
Root placement patterns in allelopathic plant-plant interactions.
College of Resources and Environmental Sciences, China Agricultural University, Beijing, 100193, China.; Department of Biological Sciences, Eastern Illinois University, Charleston, IL, 61920, USA.
Plants actively respond to their neighbors by altering root placement patterns. Neighbor-modulated root responses involve root detection and interactions mediated by root-secreted functional metabolites. However, chemically mediated root placement patterns and their underlying mechanisms remain elusive. We used an allelopathic wheat model system challenged with 60 target species to identify root placement responses in window rhizobox experiments. We then tested root responses and their biochemical mechanisms in incubation experiments involving the addition of activated carbon and functional metabolites with amyloplast staining and auxin localization in roots. Wheat and each target species demonstrated intrusive, avoidant or unresponsive root placement, resulting in a total of nine combined patterns. Root placement patterns were mediated by wheat allelochemicals and (-)-loliolide signaling of neighbor species. In particular, (-)-loliolide triggered wheat allelochemical production that altered root growth and placement, degraded starch grains in the root cap and induced uneven distribution of auxin in target species roots. Root placement patterns in wheat-neighbor interactions were perception dependent and species dependent. Signaling (-)-loliolide induced the production and release of wheat allelochemicals that modulated root placement patterns. Therefore, root placement patterns are generated by both signaling chemicals and allelochemicals in allelopathic plant-plant interactions.
PMID: 36263726
New Phytol , IF:10.151 , 2023 Jan , V237 (2) : P483-496 doi: 10.1111/nph.18556
The RhLOL1-RhILR3 module mediates cytokinin-induced petal abscission in rose.
Beijing Key Laboratory of Development and Quality Control of Ornamental Crops, Department of Ornamental Horticulture, College of Horticulture, China Agricultural University, Beijing, 100193, China.; Crops Pathology and Genetic Research Unit, United States Department of Agriculture, Agricultural Research Service, Davis, CA, 95616, USA.; Department of Plant Sciences, University of California at Davis, Davis, CA, 95616, USA.
In many plant species, petal abscission can be considered the final step of petal senescence. Cytokinins (CKs) are powerful suppressors of petal senescence; however, their role in petal abscission is ambiguous. Here, we observed that, in rose (Rosa hybrida), biologically active CK is accumulated during petal abscission and acts as an accelerator of the abscission process. Using a combination of reverse genetics, and molecular and biochemical techniques, we explored the roles of a LESION SIMULATING DISEASE1 (LSD1) family member RhLOL1 interacting with a bHLH transcription factor RhILR3 in CK-induced petal abscission. Silencing RhLOL1 delays rose petal abscission, while the overexpression of its ortholog SlLOL1 in tomato (Solanum lycopersicum) promotes pedicel abscission, indicating the conserved function of LOL1 in activating plant floral organ abscission. In addition, we identify a bHLH transcription factor, RhILR3, that interacts with RhLOL1. We show that RhILR3 binds to the promoters of the auxin signaling repressor auxin/indole-3-acetic acid (Aux/IAA) genes to inhibit their expression; however, the interaction of RhLOL1 with RhILR3 activates the expression of the Aux/IAA genes including RhIAA4-1. Silencing RhIAA4-1 delays rose petal abscission. Our results thus reveal a RhLOL1-RhILR3 regulatory module involved in CK-induced petal abscission via the regulation of the expression of the Aux/IAA genes.
PMID: 36263705
New Phytol , IF:10.151 , 2023 Jan , V237 (1) : P78-87 doi: 10.1111/nph.18536
SUE4, a novel PIN1-interacting membrane protein, regulates acropetal auxin transport in response to sulfur deficiency.
Division of Life Sciences and Medicine, Hefei National Science Center for Physical Sciences at the Microscale, University of Science and Technology of China, The Innovation Academy of Seed Design, Chinese Academy of Sciences, Hefei, Anhui Province, 230027, China.; Division of Molecular & Cell Biophysics, Hefei National Science Center for Physical Sciences at the Microscale, University of Science and Technology of China, The Innovation Academy of Seed Design, Chinese Academy of Sciences, Hefei, Anhui Province, 230027, China.; College of Resources and Environment, Fujian Agriculture and Forestry University, Fuzhou, Fujian Province, 350002, China.; State Key Laboratory of Plant Genomics, National Center for Plant Gene Research, Institute of Genetics and Developmental Biology, Innovation Academy for Seed Design, Chinese Academy of Sciences, Beijing, 100101, China.; State Key Laboratory of Plant Cell and Chromosome Engineering, Institute of Genetics and Developmental Biology, Innovation Academy for Seed Design, Chinese Academy of Sciences, Beijing, 100101, China.; College of Environmental and Resources Sciences, Zhejiang University, Hangzhou, Zhejiang Province, 310058, China.; Shanghai Key Laboratory of Plant Functional Genomics and Resources, Shanghai Chenshan Botanical Garden, Shanghai, 201602, China.
Sulfur (S) is an essential macronutrient for plants and a signaling molecule in abiotic stress responses. It is known that S availability modulates root system architecture; however, the underlying molecular mechanisms are largely unknown. We previously reported an Arabidopsis gain-of-function mutant sulfate utilization efficiency4 (sue4) that could tolerate S deficiency during germination and early seedling growth with faster primary root elongation. Here, we report that SUE4, a novel plasma membrane-localized protein, interacts with the polar auxin transporter PIN1, resulting in reduced PIN1 protein levels and thus decreasing auxin transport to the root tips, which promotes primary root elongation. Moreover, SUE4 is induced by sulfate deficiency, consistent with its role in root elongation. Further analyses showed that the SUE4-PIN1 interaction decreased PIN1 levels, possibly through 26 S proteasome-mediated degradation. Taken together, our finding of SUE4-mediated root elongation is consistent with root adaptation to highly mobile sulfate in soil, thus revealing a novel component in the adaptive response of roots to S deficiency.
PMID: 36226797
New Phytol , IF:10.151 , 2023 Jan , V237 (2) : P408-413 doi: 10.1111/nph.18487
Systemic control of plant regeneration and wound repair.
The Institute of Plant Sciences, Faculty of Agriculture, The Hebrew University, Rehovot, 761000, Israel.
Plants have a broad capacity to regenerate damaged organs. The study of wounding in multiple developmental systems has uncovered many of the molecular properties underlying plants' competence for regeneration at the local cellular level. However, in nature, wounding is rarely localized to one place, and plants need to coordinate regeneration responses at multiple tissues with environmental conditions and their physiological state. Here, we review the evidence for systemic signals that regulate regeneration on a plant-wide level. We focus on the role of auxin and sugars as short- and long-range signals in natural wounding contexts and discuss the varied origin of these signals in different regeneration scenarios. Together, this evidence calls for a broader, system-wide view of plant regeneration competence.
PMID: 36101501
Plant Biotechnol J , IF:9.803 , 2023 Feb doi: 10.1111/pbi.14031
LAZY3 interacts with LAZY2 to regulate tiller angle by modulating shoot gravity perception in rice.
Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, China.; University of Chinese Academy of Sciences, Beijing, China.; College of Advanced Agricultural Sciences, Zhejiang A&F University, Hangzhou, China.; State Key Laboratory of Crop Biology, College of Life Sciences, Shandong Agricultural University, Tai'an, China.
Starch biosynthesis in gravity-sensing tissues of rice shoot determines the magnitude of rice shoot gravitropism and thus tiller angle. However, the molecular mechanism underlying starch biosynthesis in rice gravity-sensing tissues is still unclear. We characterized a novel tiller angle gene LAZY3 (LA3) in rice through map-based cloning. Biochemical, molecular and genetic studies further demonstrated the essential roles of LA3 in gravity perception of rice shoot and tiller angle control. The shoot gravitropism and lateral auxin transport were defective in la3 mutant upon gravistimulation. We showed that LA3 encodes a chloroplast-localized tryptophan-rich protein associated with starch granules via Tryptophan-rich region (TRR) domain. Moreover, LA3 could interact with the starch biosynthesis regulator LA2, determining starch granule formation in shoot gravity-sensing tissues. LA3 and LA2 negatively regulate tiller angle in the same pathway acting upstream of LA1 to mediate asymmetric distribution of auxin. Our study defined LA3 as an indispensable factor of starch biosynthesis in rice gravity-sensing tissues that greatly broadens current understanding in the molecular mechanisms underlying the starch granule formation in gravity-sensing tissues, and provides new insights into the regulatory mechanism of shoot gravitropism and rice tiller angle.
PMID: 36789453
Plant Biotechnol J , IF:9.803 , 2023 Mar , V21 (3) : P591-605 doi: 10.1111/pbi.13974
Profiling of phytohormone-specific microRNAs and characterization of the miR160-ARF1 module involved in glandular trichome development and artemisinin biosynthesis in Artemisia annua.
Medical School of Nantong University, Nantong, China.; School of Food and Bioengineering, Fujian Polytechnic Normal University, Fuqing, China.; Department of Pharmaceutical Botany, School of Pharmacy, Naval Medical University, Shanghai, China.; Research and Development Center of Chinese Medicine Resources and Biotechnology, Shanghai University of Traditional Chinese Medicine, Shanghai, China.; Institute of Edible Fungi, Shanghai Academy of Agricultural Sciences, National Engineering Research Center of Edible Fungi, Shanghai, China.; Key Laboratory of Edible Fungi Resources and Utilization (South), Ministry of Agriculture, Shanghai, China.; Innovative Drug R&D Center, College of Life Sciences, Huaibei Normal University, Huaibei, China.
MicroRNAs (miRNAs) play crucial roles in plant development and secondary metabolism through different modes of sequence-specific interaction with their targets. Artemisinin biosynthesis is extensively regulated by phytohormones. However, the function of phytohormone-responsive miRNAs in artemisinin biosynthesis remains enigmatic. Thus, we combined the analysis of transcriptomics, small RNAs, and the degradome to generate a comprehensive resource for identifying key miRNA-target circuits involved in the phytohormone-induced process of artemisinin biosynthesis in Artemisia annua. In total, 151 conserved and 52 novel miRNAs and their 4132 targets were determined. Based on the differential expression analysis, miR160 was selected as a potential miRNA involved in artemisinin synthesis. Overexpressing MIR160 significantly impaired glandular trichome formation and suppressed artemisinin biosynthesis in A. annua, while repressing its expression resulted in the opposite effect, indicating that miR160 negatively regulates glandular trichome development and artemisinin biosynthesis. RNA ligase-mediated 5' RACE and transient transformation assays showed that miR160 mediates the RNA cleavage of Auxin Response Factor 1 (ARF1) in A. annua. Furthermore, ARF1 was shown to increase artemisinin synthesis by activating AaDBR2 expression. Taken together, our results reveal the intrinsic link between the miR160-ARF1 module and artemisinin biosynthesis, and may expedite the innovation of metabolic engineering approaches for high and stable production of artemisinin in the future.
PMID: 36478140
Plant Biotechnol J , IF:9.803 , 2023 Jan , V21 (1) : P122-135 doi: 10.1111/pbi.13930
A HST1-like gene controls tiller angle through regulating endogenous auxin in common wheat.
National Key Laboratory of Wheat and Maize Crop Science / CIMMYT-China Wheat and Maize Joint Research Center /Agronomy College, Henan Agricultural University, Zhengzhou, China.
Tiller angle is one of the most important agronomic traits and one key factor for wheat ideal plant architecture, which can both increase photosynthetic efficiency and greatly enhance grain yield. Here, a deacetylase HST1-like (TaHST1L) gene controlling wheat tiller angle was identified by the combination of a genome-wide association study (GWAS) and bulked segregant analysis (BSA). Ethyl methane sulfonate (EMS)-mutagenized tetraploid wheat lines with the premature stop codon of TaHST1L exhibited significantly smaller tiller angles than the wild type. TaHST1L-overexpressing (OE) plants exhibited significantly larger tiller angles and increased tiller numbers in both winter and spring wheat, while TaHST1L-silenced RNAi plants displayed significantly smaller tiller angles and decreased tiller numbers. Moreover, TaHST1L strongly interacted with TaIAA17 and inhibited its expression at the protein level, and thus possibly improved the content of endogenous auxin in the basal tissue of tillers. The transcriptomics and metabolomics results indicated that TaHST1L might change plant architecture by mediating auxin signal transduction and regulating endogenous auxin levels. In addition, a 242-bp insertion/deletion (InDel) in the TaHST1L-A1 promoter altered transcriptional activity and TaHST1L-A1b allele with the 242-bp insertion widened the tiller angle of TaHST1L-OE transgenic rice plants. Wheat varieties with TaHST1L-A1b allele possessed the increased tiller angle and grain yield. Further analysis in wheat and its progenitors indicated that the 242-bp InDel possibly originated from wild emmer and was strongly domesticated in the current varieties. Therefore, TaHST1L involved in the auxin signalling pathway showed the big potential to improve wheat yield by controlling plant architecture.
PMID: 36128872
Cell Rep , IF:9.423 , 2023 Feb , V42 (2) : P112130 doi: 10.1016/j.celrep.2023.112130
Physcomitrium patens PpRIC, an ancestral CRIB-domain ROP effector, inhibits auxin-induced differentiation of apical initial cells.
Cell Biology, Department of Biology, University Erlangen-Nuremberg, 91058 Erlangen, Germany.; Physiology and Environmental Toxicology, Department of Organismal Biology, Uppsala University, 75236 Uppsala, Sweden.; Umea Plant Science Centre, Department of Forest Genetics and Plant Physiology, Swedish University of Agricultural Sciences, 90183 Umea, Sweden.; Cell Biology, Department of Biology, University Erlangen-Nuremberg, 91058 Erlangen, Germany. Electronic address: benedikt.kost@fau.de.
RHO guanosine triphosphatases are important eukaryotic regulators of cell differentiation and behavior. Plant ROP (RHO of plant) family members activate specific, incompletely characterized downstream signaling. The structurally simple land plant Physcomitrium patens is missing homologs of key animal and flowering plant RHO effectors but contains a single CRIB (CDC42/RAC interactive binding)-domain-containing RIC (ROP-interacting CRIB-containing) protein (PpRIC). Protonemal P. patens filaments elongate based on regular division and PpROP-dependent tip growth of apical initial cells, which upon stimulation by the hormone auxin differentiate caulonemal characteristics. PpRIC interacts with active PpROP1, co-localizes with this protein at the plasma membrane at the tip of apical initial cells, and accumulates in the nucleus. Remarkably, PpRIC is not required for tip growth but is targeted to the nucleus to block caulonema differentiation downstream of auxin-controlled gene expression. These observations establish functions of PpRIC in mediating crosstalk between ROP and auxin signaling, which contributes to the maintenance of apical initial cell identity.
PMID: 36790931
Cell Rep , IF:9.423 , 2023 Jan , V42 (1) : P111913 doi: 10.1016/j.celrep.2022.111913
Control of lateral root initiation by DA3 in Arabidopsis.
School of Life Sciences, Anhui Agricultural University, Hefei 230036, China; Department of Biological Sciences, Faculty of Science, National University of Singapore, Singapore 117543, Singapore.; State Key Laboratory of Plant Cell and Chromosome, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China.; School of Life Sciences, Anhui Agricultural University, Hefei 230036, China.; Department of Biological Sciences, Faculty of Science, National University of Singapore, Singapore 117543, Singapore.; School of Science, Anhui Agricultural University, Hefei 230036, China.; Department of Biological Sciences, Faculty of Science, National University of Singapore, Singapore 117543, Singapore. Electronic address: dbsyuhao@nus.edu.sg.
Lateral root (LR) initiation is controlled by the pericycle and the neighboring endodermis in Arabidopsis. Here, we demonstrate that UBIQUITIN-SPECIFIC PROTEASE14/DA3 regulates LR initiation by modulating auxin signaling in the pericycle and endodermis. DA3 negatively affects the mRNA and protein levels of AUXIN RESPONSE FACTOR7 (ARF7) and ARF19 in the pericycle and endodermis but positively regulates the protein stability of SHORT HYPOCOTYL 2 (SHY2/IAA3), an auxin signaling repressor, in the endodermis. We show that DA3 interacts with ARF7 and ARF19, inhibiting their binding to the locus of LATERAL ORGAN BOUNDARY DOMAIN16 (LBD16) to repress its expression in the pericycle. SHY2 also interacts with ARF7 and ARF19 in the endodermis and enhances the DA3 repressive effect on ARF7 and ARF19, thus modulating LBD16 expression in the pericycle. Overall, our findings show that DA3 acts with SHY2, ARF7, and ARF19 to coordinate auxin signaling in the pericycle and endodermis to control LR initiation in Arabidopsis.
PMID: 36640335
EMBO Rep , IF:8.807 , 2023 Jan : Pe56271 doi: 10.15252/embr.202256271
ABCB-mediated shootward auxin transport feeds into the root clock.
Department of Plant Biotechnology and Bioinformatics, Ghent University, Ghent, Belgium.; Center for Plant Systems Biology, VIB, Ghent, Belgium.; School of Plant Sciences and Food Security, Tel-Aviv University, Tel-Aviv, Israel.; Department of Biology, University of Fribourg, Fribourg, Switzerland.; Section of Cell and Developmental Biology, University of California San Diego, La Jolla, CA, USA.; Department of Plants and Crops, Ghent University, Ghent, Belgium.; Lab of Plant Growth Analysis, Ghent University Global Campus, Incheon, Republic of Korea.
Although strongly influenced by environmental conditions, lateral root (LR) positioning along the primary root appears to follow obediently an internal spacing mechanism dictated by auxin oscillations that prepattern the primary root, referred to as the root clock. Surprisingly, none of the hitherto characterized PIN- and ABCB-type auxin transporters seem to be involved in this LR prepatterning mechanism. Here, we characterize ABCB15, 16, 17, 18, and 22 (ABCB15-22) as novel auxin-transporting ABCBs. Knock-down and genome editing of this genetically linked group of ABCBs caused strongly reduced LR densities. These phenotypes were correlated with reduced amplitude, but not reduced frequency of the root clock oscillation. High-resolution auxin transport assays and tissue-specific silencing revealed contributions of ABCB15-22 to shootward auxin transport in the lateral root cap (LRC) and epidermis, thereby explaining the reduced auxin oscillation. Jointly, these data support a model in which LRC-derived auxin contributes to the root clock amplitude.
PMID: 36718777
Plant Physiol , IF:8.34 , 2023 Feb doi: 10.1093/plphys/kiad099
MicroRNA156ab regulates apple plant growth and drought tolerance by targeting transcription factor MsSPL13.
Department of Pomology, College of Horticulture, China Agricultural University, Beijing 100193, China.
Drought stress substantially reduces the productivity of apple plants and severely restricts the development of the apple industry. Malus sieversii, a wild apple with excellent drought resistance, is a valuable wild resource for rootstock improvement of cultivated apple (Malus domestica). miRNAs and their targets play essential roles in plant growth and stress responses, but their roles in drought stress responses in apple are unknown. Here, we demonstrate that microRNA156ab is upregulated in M. sieversii in response to drought stress. Overexpressing msi-miR156ab promoted auxin accumulation, maintained the growth of apple plants, and increased plant resistance to osmotic stress. Antioxidant enzyme activities and proline contents were also increased in miR156ab-OE transgenic apple lines, which improved drought resistance. The SQUAMOSA PROMOTER BINDING PROTEIN-LIKE (SPL) transcription factor MsSPL13 is the target of msi-miR156ab, as demonstrated by 5-RACE and dual luciferase assays. Heterologous expression of MsSPL13 decreased auxin contents and inhibited growth in Arabidopsis (Arabidopsis thaliana) under normal and stress conditions. The activities of antioxidant enzymes were also suppressed in MsSPL13-OE transgenic Arabidopsis, reducing drought resistance. We showed that MsSPL13 regulates the expression of the auxin-related genes MsYUCCA5, PIN-FORMED7 (MsPIN7), and Gretchen Hagen3-5 (MsGH3-5) by binding to the GTAC cis-elements in their promoters, thereby regulating auxin metabolism. Finally, we demonstrated that the miR156ab-SPL13 module is involved in mediating the difference in auxin metabolism and stress responses between the M. sieversii and M26 (M. domestica) rootstocks. Overall, these findings reveal that the miR156ab-SPL13 module enhances drought stress tolerance in apples by regulating auxin metabolism and antioxidant enzyme activities.
PMID: 36805285
Plant Physiol , IF:8.34 , 2023 Feb doi: 10.1093/plphys/kiad101
To grow up or not: SUMOylation of IAA7 acts as a key molecular switch of auxin signaling.
School of Biological Sciences, The University of Hong Kong, Hong Kong, China.; State Key Laboratory of Agrobiotechnology, The Chinese University of Hong Kong, Hong Kong, China.
PMID: 36797804
Plant Physiol , IF:8.34 , 2023 Feb doi: 10.1093/plphys/kiad086
Wheat AUXIN RESPONSE FACTOR 15 delays senescence through interaction at the TaNAM1 locus.
Department of Plant Biology and Genome Center, University of California, Davis, California 95616.
PMID: 36788762
Plant Physiol , IF:8.34 , 2023 Feb doi: 10.1093/plphys/kiad073
Dynamic GOLVEN-ROOT GROWTH FACTOR 1 INSENSITIVE signaling in the root cap mediates root gravitropism.
Department of Plant Biotechnology and Bioinformatics, Ghent University, Technologiepark 71, B-9052 Ghent, Belgium.; VIB-UGent Center for Plant Systems Biology, Technologiepark 71, B-9052 Ghent, Belgium.
Throughout exploration of the soil, roots interact with their environment and adapt to different conditions. Directional root growth is guided by asymmetric molecular patterns but how these become established or are dynamically regulated is poorly understood. Asymmetric gradients of the phytohormone auxin are established during root gravitropism, mainly through directional transport mediated by polarized auxin transporters. Upon gravistimulation, PIN-FORMED2 (PIN2) is differentially distributed and accumulates at the lower root side to facilitate asymmetric auxin transport up to the elongation zone where it inhibits cell elongation. GOLVEN (GLV) peptides function in gravitropism by affecting PIN2 abundance in epidermal cells. In addition, GLV signaling through ROOT GROWTH FACTOR 1 INSENSITIVE (RGI) receptors regulates root apical meristem maintenance. Here, we show that GLV-RGI signaling in these two processes in Arabidopsis (Arabidopsis thaliana) can be mapped to different cells in the root tip and that, in the case of gravitropism, it operates mainly in the lateral root cap (LRC) to maintain PIN2 levels at the plasma membrane. Furthermore, we found that GLV signaling upregulates the phosphorylation level of PIN2 in an RGI-dependent manner. In addition, we demonstrated that the RGI5 receptor is asymmetrically distributed in the LRC and accumulates in the lower side of the LRC after gravistimulation. Asymmetric GLV-RGI signaling in the root cap likely accounts for differential PIN2 abundance at the plasma membrane to temporarily support auxin transport up to the elongation zone thereby representing an additional level of control on the asymmetrical auxin flux to mediate differential growth of the root.
PMID: 36747317
Plant Physiol , IF:8.34 , 2023 Feb doi: 10.1093/plphys/kiad045
Sucrose-induced auxin conjugate hydrolase restores symbiosis in a Medicago cytokinin perception mutant.
Department of Biochemistry, University of Calcutta, Kolkata 700019, India.
Rhizobia-legume interactions recruit cytokinin for the induction of nodule primordia in the cortex. Cytokinin signaling regulates auxin transport and biosynthesis, causing local auxin accumulation which triggers cortical cell division. Since sugar signaling can trigger auxin responses, we explored whether sugar treatments could rescue symbiosis in the Medicago truncatula Cytokinin Response 1 mutant (cre1.) Herein we demonstrate that sucrose and its nonmetabolizable isomer turanose can trigger auxin response and recover functional symbiosis in cre1, indicating sucrose signaling to be necessary for restoration of symbiosis. In both M. truncatula A17 (wild-type) and cre1, sucrose signaling significantly upregulated IAA-Ala Resistant 3 (IAR33), encoding an auxin conjugate hydrolase, in rhizobia-infected as well as in uninfected roots. Knockdown of IAR33 (IAR33-KD) significantly reduced nodulation in A17, highlighting the importance of deconjugation-mediated auxin accumulation during nodule inception. In cre1, IAR33-KD restricted the sucrose mediated restoration of functional symbiosis, suggesting deconjugation-mediated auxin accumulation plays a key role in the absence of CRE1-mediated auxin biosynthesis and transport control. Overexpression of IAR33 also restored functional symbiosis in cre1, further suggesting thatIAR33 mediates auxin accumulation in response to sucrose signaling. Since all the observed sucrose mediated responses were common to A17 and cre1, deconjugation-mediated auxin response appeared to be independent of CRE1, whichnormally governs local auxin accumulation in the presence of rhizobia. We propose that sucrose-dependent restoration of symbiosis in cre1 occurs by the activation of IAR33-mediated auxin deconjugation.
PMID: 36722159
Plant Physiol , IF:8.34 , 2023 Jan doi: 10.1093/plphys/kiad038
Causes and consequences of endogenous hypoxia on growth and metabolism of developing maize kernels.
Leibniz-Institut fur Pflanzengenetik und Kulturpflanzenforschung, Corrensstrasse, 06466 Seeland-Gatersleben, Germany.; University of Florida, Horticultural Sciences Department, Fifield Hall, 2550 Hull Rd., PO Box 110690, Gainesville, FL, 32611, USA.; KU Leuven - University of Leuven, BIOSYST-MeBioS, Willem de Croylaan 42, B-3001 Leuven, Belgium.
Maize (Zea mays) kernels are the largest cereal grains, and their endosperm is severely oxygen deficient during grain fill. The causes, dynamics, and mechanisms of acclimation to hypoxia are minimally understood. Here, we demonstrate that hypoxia develops in the small, growing endosperm, but not the nucellus, and becomes the standard state, regardless of diverse structural and genetic perturbations in modern maize (B73, popcorn, sweet corn), mutants (sweet4c, glossy6, waxy), and non-domesticated wild relatives (teosintes and Tripsacum species). We also uncovered an interconnected void space at the chalazal pericarp, providing superior oxygen supply to the placental tissues and basal endosperm transfer layer. Modelling indicated a very high diffusion resistance inside the endosperm, which, together with internal oxygen consumption, could generate steep oxygen gradients at the endosperm surface. Manipulation of oxygen supply induced reciprocal shifts in gene expression implicated in controlling mitochondrial functions (23.6 kDa Heat-Shock Protein, Voltage Dependent Anion Channel 2) and multiple signalling pathways (core hypoxia genes, cyclic nucleotide metabolism, ethylene synthesis). Metabolite profiling revealed oxygen-dependent shifts in mitochondrial pathways, ascorbate metabolism, starch synthesis, and auxin degradation. Long-term elevated oxygen supply enhanced the rate of kernel development. Altogether, evidence here supports a mechanistic framework for the establishment of and acclimation to hypoxia in the maize endosperm.
PMID: 36691698
Plant Physiol , IF:8.34 , 2023 Jan doi: 10.1093/plphys/kiad034
Auxin-independent effects of apical dominance induce changes in phytohormones correlated with bud outgrowth.
ARC Centre of Excellence for Plant Success in Nature and Agriculture, School of Biological Sciences, The University of Queensland, Brisbane, QLD 4072, Australia.; School of Biological Sciences, The University of Queensland, Brisbane, QLD 4072, Australia.
The inhibition of shoot branching by the growing shoot tip of plants, termed apical dominance, was originally thought to be mediated by auxin. Recently the importance of the shoot tip sink strength during apical dominance has re-emerged with recent studies highlighting roles for sugars in promoting branching. This raises many unanswered questions on the relative roles of auxin and sugars in apical dominance. Here we show that auxin depletion after decapitation is not always the initial trigger of rapid cytokinin increases in buds that are instead correlated with enhanced sugars. Auxin may also act through strigolactones which have been shown to suppress branching after decapitation, but here we show that strigolactones do not have a significant effect on initial bud outgrowth after decapitation. We report here that when sucrose or cytokinin is abundant, strigolactones are less inhibitory during the bud release stage compared to during later stages and that strigolactone treatment rapidly inhibits cytokinin accumulation in pea (Pisum sativum) axillary buds of intact plants. After initial bud release, we find an important role of gibberellin in promoting sustained bud growth downstream of auxin. We are therefore able to suggest a model of apical dominance that integrates auxin, sucrose, strigolactones, cytokinins and gibberellins and describes differences in signalling across stages of bud release to sustained growth.
PMID: 36690819
Plant Physiol , IF:8.34 , 2023 Jan doi: 10.1093/plphys/kiad006
Roles of very-long-chain fatty acids in compound leaf patterning in Medicago truncatula.
The Key Laboratory of Plant Development and Environmental Adaptation Biology, Ministry of Education, School of Life Sciences, Shandong University, Qingdao 266101, China.; Grassland Agri-Husbandry Research Center, Qingdao Agricultural University, Qingdao 266109, China.; College of Life Sciences, Shandong Normal University, Jinan 250014, China.; State Key Laboratory of Biocatalysis and Enzyme Engineering, School of Life Sciences, Hubei University, Wuhan 430062, China.; Hunan Provincial Key Laboratory of Phytohormones and Growth Development, Hunan Provincial Key Laboratory for Crop Germplasm Innovation and Utilization, Hunan Agricultural University, Changsha 410128, China.; Institute of Agricultural Biosciences, Oklahoma State University, 3210 Sam Noble Parkway, Ardmore, Oklahoma 73401, USA.
Plant cuticles are composed of hydrophobic cuticular waxes and cutin. Very long-chain fatty acids (VLCFAs) are components of epidermal waxes and the plasma membrane and are involved in organ morphogenesis. By screening a barrelclover (Medicago truncatula) mutant population tagged by the transposable element of tobacco (Nicotiana tabacum) cell type1 (Tnt1), we identified two types of mutants with unopened flower phenotypes, named unopened flower1 (uof1) and uof2. Both UOF1 and UOF2 encode enzymes that are involved in the biosynthesis of VLCFAs and cuticular wax. Comparative analysis of the mutants indicated that the mutation in UOF1, but not UOF2, leads to increased number of leaflets in M. truncatula. UOF1 was specifically expressed in the outermost cell layer (L1) of the shoot apical meristem (SAM) and leaf primordia. The uof1 mutants displayed defects in VLCFAs-mediated plasma membrane integrity, resulting in the disordered localization of the PIN-FORMED1 (PIN1) ortholog SMOOTH LEAF MARGIN1 (SLM1) in M. truncatula. Our work demonstrates that the UOF1-mediated biosynthesis of VLCFAs in L1 is critical for compound leaf patterning, which is associated with the polarization of the auxin efflux carrier in M. truncatula.
PMID: 36617225
Plant Physiol , IF:8.34 , 2023 Feb , V191 (2) : P834-836 doi: 10.1093/plphys/kiac535
Wheat AUXIN RESPONSE FACTOR 15 delays senescence through competitive interaction at the TaNAM1 locus.
Department of Plant Biology and Genome Center, University of California, Davis, California 95616, USA.
PMID: 36454670
Plant Physiol , IF:8.34 , 2023 Feb , V191 (2) : P1365-1382 doi: 10.1093/plphys/kiac530
SYNTAXIN OF PLANTS81 regulates root meristem activity and stem cell niche maintenance via ROS signaling.
Key Laboratory of Saline-alkali Vegetation Ecology Restoration, Ministry of Education, College of Life Sciences, Northeast Forestry University, Harbin 150040, China.; Peking University Institute of Advanced Agricultural Sciences, Shandong Laboratory of Advanced Agricultural Sciences at Weifang, Weifang, Shandong 261000, China.; Key Laboratory of Soybean Molecular Design Breeding, Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, Changchun 130102, China.; Institute of Advanced Biotechnology and School of Life Sciences, Southern University of Science and Technology, Shenzhen 518055, China.; Center for Advanced Bioindustry Technologies, Chinese Academy of Agricultural Sciences, Beijing 100081, China.
Root growth and development depend on continuous cell division and differentiation in root tips. In these processes, reactive oxygen species (ROS) play a critical role as signaling molecules. However, few ROS signaling regulators have been identified. In this study, we found knockdown of a syntaxin gene, SYNTAXIN OF PLANTS81 in Arabidopsis thaliana (AtSYP81) resulted in a severe reduction in root meristem activity and disruption of root stem cell niche (SCN) identity. Subsequently, we found AtSYP81 was highly expressed in roots and localized on the endoplasmic reticulum (ER). Interestingly, the reduced expression of AtSYP81 conferred a decreased number of peroxisomes in root meristem cells, raising a possibility that AtSYP81 regulates root development through peroxisome-mediated ROS production. Further transcriptome analysis revealed that class III peroxidases, which are responsible for intracellular ROS homeostasis, showed significantly changed expression in the atsyp81 mutants and AtSYP81 overexpression lines, adding evidence of the regulatory role of AtSYP81 in ROS signaling. Accordingly, rescuing the decreased ROS level via applying ROS donors effectively restored the defects in root meristem activity and SCN identity in the atsyp81 mutants. APETALA2 (AP2) transcription factors PLETHORA1 and 2 (PLT1 and PLT2) were then established as the downstream effectors in this pathway, while potential crosstalk between ROS signaling and auxin signaling was also indicated. Taken together, our findings suggest that AtSYP81 regulates root meristem activity and maintains root SCN identity by controlling peroxisome- and peroxidase-mediated ROS homeostasis, thus both broadening and deepening our understanding of the biological roles of SNARE proteins and ROS signaling.
PMID: 36427205
Plant Physiol , IF:8.34 , 2023 Jan , V191 (1) : P496-514 doi: 10.1093/plphys/kiac516
The B-box transcription factor IbBBX29 regulates leaf development and flavonoid biosynthesis in sweet potato.
Key Laboratory of Sweet Potato Biology and Biotechnology, Ministry of Agriculture and Rural Affairs/Beijing Key Laboratory of Crop Genetic Improvement/Laboratory of Crop Heterosis and Utilization and Joint Laboratory for International Cooperation in Crop Molecular Breeding, Ministry of Education, College of Agronomy and Biotechnology, China Agricultural University, Beijing 100193, China.; Sanya Institute of China Agricultural University, Hainan 572025, China.; Provincial Key Laboratory of Agrobiology, Institute of Food Crops, Jiangsu Academy of Agricultural Sciences, Nanjing 210000, China.; Institute of Grain and Oil Crops, Yantai Academy of Agricultural Sciences, Yantai 265500, China.; College of Agronomy and Biotechnology, Southwest University, Chongqing 400715, China.
Plant flavonoids are valuable natural antioxidants. Sweet potato (Ipomoea batatas) leaves are rich in flavonoids, regenerate rapidly, and can adapt to harsh environments, making them an ideal material for flavonoid biofortification. Here, we demonstrate that the B-box (BBX) family transcription factor IbBBX29 regulates the flavonoid contents and development of sweet potato leaves. IbBBX29 was highly expressed in sweet potato leaves and significantly induced by auxin (IAA). Overexpression of IbBBX29 contributed to a 21.37%-70.94% increase in leaf biomass, a 12.08%-21.85% increase in IAA levels, and a 31.33%-63.03% increase in flavonoid accumulation in sweet potato, whereas silencing this gene produced opposite effects. Heterologous expression of IbBBX29 in Arabidopsis (Arabidopsis thaliana) led to a dwarfed phenotype, along with enhanced IAA and flavonoid accumulation. RNA-seq analysis revealed that IbBBX29 modulates the expression of genes involved in the IAA signaling and flavonoid biosynthesis pathways. Chromatin immunoprecipitation-quantitative polymerase chain reaction and electrophoretic mobility shift assay indicated that IbBBX29 targets key genes of IAA signaling and flavonoid biosynthesis to activate their expression by binding to specific T/G-boxes in their promoters, especially those adjacent to the transcription start site. Moreover, IbBBX29 physically interacted with developmental and phenylpropanoid biosynthesis-related proteins, such as AGAMOUS-LIKE 21 protein IbAGL21 and MYB308-like protein IbMYB308L. Finally, overexpressing IbBBX29 also increased flavonoid contents in sweet potato storage roots. These findings indicate that IbBBX29 plays a pivotal role in regulating IAA-mediated leaf development and flavonoid biosynthesis in sweet potato and Arabidopsis, providing a candidate gene for flavonoid biofortification in plants.
PMID: 36377782
Plant Physiol , IF:8.34 , 2023 Jan , V191 (1) : P463-478 doi: 10.1093/plphys/kiac513
Transcription factors KNAT3 and KNAT4 are essential for integument and ovule formation in Arabidopsis.
The State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, South China Agricultural University, Guangzhou 510642, China.; Guangdong Key Laboratory for Innovative Development and Utilization of Forest Plant Germplasm, College of Forestry and Landscape Architectures, South China Agricultural University, Guangzhou 510642, China.; Umea Plant Science Centre, Department of Forest Genetics and Plant Physiology, Swedish University of Agricultural Sciences, Umea 90183, Sweden.; Tianjin Key Laboratory of Protein Sciences, Department of Plant Biology and Ecology, College of Life Sciences, Nankai University, Tianjin 300071, China.; Bioproduction Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Ibaraki, Japan.; Guangdong Laboratory of Lingnan Modern Agriculture, Guangzhou 510642, China.
Integuments form important protective cell layers surrounding the developing ovules in gymno- and angiosperms. Although several genes have been shown to influence the development of integuments, the transcriptional regulatory mechanism is still poorly understood. In this work, we report that the Class II KNOTTED1-LIKE HOMEOBOX (KNOX II) transcription factors KNOTTED1-LIKE HOMEBOX GENE 3 (KNAT3) and KNAT4 regulate integument development in Arabidopsis (Arabidopsis thaliana). KNAT3 and KNAT4 were co-expressed in inflorescences and especially in young developing ovules. The loss-of-function double mutant knat3 knat4 showed an infertility phenotype, in which both inner and outer integuments of the ovule are arrested at an early stage and form an amorphous structure as in the bell1 (bel1) mutant. The expression of chimeric KNAT3- and KNAT4-EAR motif repression domain (SRDX repressors) resulted in severe seed abortion. Protein-protein interaction assays demonstrated that KNAT3 and KNAT4 interact with each other and also with INNER NO OUTER (INO), a key transcription factor required for the outer integument formation. Transcriptome analysis showed that the expression of genes related with integument development is influenced in the knat3 knat4 mutant. The knat3 knat4 mutant also had a lower indole-3-acetic acid (IAA) content, and some auxin signaling pathway genes were downregulated. Moreover, transactivation analysis indicated that KNAT3/4 and INO activate the auxin signaling gene IAA INDUCIBLE 14 (IAA14). Taken together, our study identified KNAT3 and KNAT4 as key factors in integument development in Arabidopsis.
PMID: 36342216
Plant Physiol , IF:8.34 , 2023 Jan , V191 (1) : P772-788 doi: 10.1093/plphys/kiac511
HEAT-RESPONSIVE PROTEIN regulates heat stress via fine-tuning ethylene/auxin signaling pathways in cotton.
Institute of Crop Science, Plant Precision Breeding Academy, Zhejiang Provincial Key Laboratory of Crop Genetic Resources, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou, China.; Institute of Plant Breeding and Biotechnology, MNS University of Agriculture, Multan, Pakistan.; National Center for Gene Research, State Key Laboratory of Plant Molecular Genetics, CAS Center for Excellence in Molecular Plant Sciences, Shanghai Institute of Plant Physiology and Ecology, Chinese Academy of Sciences, Shanghai, China.
Plants sense and respond to fluctuating temperature and light conditions during the circadian cycle; however, the molecular mechanism underlying plant adaptability during daytime warm conditions remains poorly understood. In this study, we reveal that the ectopic regulation of a HEAT RESPONSIVE PROTEIN (GhHRP) controls the adaptation and survival of cotton (Gossypium hirsutum) plants in response to warm conditions via modulating phytohormone signaling. Increased ambient temperature promptly enhanced the binding of the phytochrome interacting factor 4 (GhPIF4)/ethylene-insensitive 3 (GhEIN3) complex to the GhHRP promoter to increase its mRNA level. The ectopic expression of GhHRP promoted the temperature-dependent accumulation of GhPIF4 transcripts and hypocotyl elongation by triggering thermoresponsive growth-related genes. Notably, the upregulation of the GhHRP/GhPIF4 complex improved plant growth via modulating the abundance of Arabidopsis thaliana auxin biosynthetic gene YUCCA8 (AtYUC8)/1-aminocyclopropane-1-carboxylate synthase 8 (AtACS8) for fine-tuning the auxin/ethylene interplay, ultimately resulting in decreased ethylene biosynthesis. GhHRP thus protects chloroplasts from photo-oxidative bursts via repressing AtACS8 and AtACS7 and upregulating AtYUC8 and the heat shock transcription factors (HSFA2), heat shock proteins (HSP70 and HSP20). Strikingly, the Deltahrp disruption mutant exhibited compromised production of HSP/YUC8 that resulted in an opposite phenotype with the loss of the ability to respond to warm conditions. Our results show that GhHRP is a heat-responsive signaling component that assists plants in confronting the dark phase and modulates auxin signaling to rescue growth under temperature fluctuations.
PMID: 36342207
Plant Physiol , IF:8.34 , 2023 Feb , V191 (2) : P1254-1271 doi: 10.1093/plphys/kiac497
The auxin response factor TaARF15-A1 negatively regulates senescence in common wheat (Triticum aestivum L.).
Key Laboratory of Crop Gene Resources and Germplasm Enhancement, Institute of Crop Sciences, Chinese Academy of Agricultural Sciences, Beijing 100081, China.; Center for Agricultural Resources Research, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Shijiazhuang 050000, China.; Institute of Cotton Research, Chinese Academy of Agricultural Sciences, Anyang 455000, China.; Institute of Wheat Research, Shanxi Agricultural University, Linfen 041000, China.
Auxin plays an important role in regulating leaf senescence. Auxin response factors (ARFs) are crucial components of the auxin signaling pathway; however, their roles in leaf senescence in cereal crops are unknown. In this study, we identified TaARF15-A1 as a negative regulator of senescence in wheat (Triticum aestivum L.) by analyzing TaARF15-A1 overexpression (OE) and RNA interference lines and CRISPR/Cas9-based arf15 mutants. OE of TaARF15-A1 delayed senescence, whereas knockdown lines and knockout mutants showed accelerated leaf senescence and grain ripening. RNA-seq analysis revealed that TaARF15-A1 delays leaf senescence by negatively regulating senescence-promoting processes and positively modulating senescence-delaying genes including senescence-associated phytohormone biosynthesis and metabolism genes as well as transcription factors (TFs). We also demonstrated that TaARF15-A1 physically interacts with TaMYC2, a core jasmonic acid (JA) signaling TF that positively modulates wheat senescence. Furthermore, TaARF15-A1 suppressed the expression of TaNAM-1 (TaNAM-A1 and TaNAM-D1) via protein-protein interaction and competition with TaMYC2 for binding to its promoter to regulate senescence. Finally, we identified two haplotypes of TaARF15-A1 in global wheat collections. Association analysis revealed that TaARF15-A1-HapI has undergone strong selection during wheat breeding in China, likely owing to its earlier maturity. Thus, we identify TaARF15-A1 as a negative regulator of senescence in common wheat and present another perspective on the crosstalk between auxin and JA signaling pathways in regulating plant senescence.
PMID: 36282536
Plant Physiol , IF:8.34 , 2023 Jan , V191 (1) : P610-625 doi: 10.1093/plphys/kiac464
Transition to ripening in tomato requires hormone-controlled genetic reprogramming initiated in gel tissue.
Laboratoire de Recherche en Sciences Vegetales-Genomique et Biotechnologie des Fruits-UMR5546, Universite de Toulouse, CNRS, UPS, Toulouse-INP, Toulouse, France.; Universite de Toulouse, INRAe/INP Toulouse, Genomique et Biotechnologie des Fruits-UMR990, Castanet-Tolosan, France.; Key Laboratory of Bio-Resource and Eco-Environment of Ministry of Education, College of Life Sciences, Sichuan University, Chengdu, Sichuan 610065, China.; Institute of Biosciences, Department of Botany, Universidade de Sao Paulo, Sao Paulo, 11461 Brazil.; Departamento de Alimentos e Nutricao Experimental, Faculdade de Ciencias Farmaceuticas, Universidade de Sao Paulo, Sao Paulo, SP, Brazil.; Metatoul-AgromiX platform, LRSV, Universite de Toulouse, CNRS, UPS, Toulouse INP, France.; MetaboHUB-MetaToul, National Infrastructure of Metabolomics and Fluxomics, Toulouse, 31077, France.
Ripening is the last stage of the developmental program in fleshy fruits. During this phase, fruits become edible and acquire their unique sensory qualities and post-harvest potential. Although our knowledge of the mechanisms that regulate fruit ripening has improved considerably over the past decades, the processes that trigger the transition to ripening remain poorly deciphered. While transcriptomic profiling of tomato (Solanum lycopersicum L.) fruit ripening to date has mainly focused on the changes occurring in pericarp tissues between the Mature Green and Breaker stages, our study addresses the changes between the Early Mature Green and Late Mature Green stages in the gel and pericarp separately. The data showed that the shift from an inability to initiate ripening to the capacity to undergo full ripening requires extensive transcriptomic reprogramming that takes place first in the locular tissues before extending to the pericarp. Genome-wide transcriptomic profiling revealed the wide diversity of transcription factor (TF) families engaged in the global reprogramming of gene expression and identified those specifically regulated at the Mature Green stage in the gel but not in the pericarp, thereby providing potential targets toward deciphering the initial factors and events that trigger the transition to ripening. The study also uncovered an extensive reformed homeostasis for most plant hormones, highlighting the multihormonal control of ripening initiation. Our data unveil the antagonistic roles of ethylene and auxin during the onset of ripening and show that auxin treatment delays fruit ripening via impairing the expression of genes required for System-2 autocatalytic ethylene production that is essential for climacteric ripening. This study unveils the detailed features of the transcriptomic reprogramming associated with the transition to ripening of tomato fruit and shows that the first changes occur in the locular gel before extending to pericarp and that a reformed auxin homeostasis is essential for the ripening to proceed.
PMID: 36200876
Plant Physiol , IF:8.34 , 2023 Jan , V191 (1) : P335-351 doi: 10.1093/plphys/kiac462
Factor of DNA methylation 1 affects woodland strawberry plant stature and organ size via DNA methylation.
Key Laboratory of Horticultural Plant Biology (Ministry of Education), Huazhong Agricultural University, Wuhan 430070, China.; Hubei Hongshan Laboratory, Wuhan 430070, China.; College of Horticulture, Anhui Agricultural University, Hefei 230036, China.; Department of Cell Biology and Molecular Genetics, University of Maryland, Mary land 20742, USA.
RNA-directed DNA methylation (RdDM) is an epigenetic process that directs silencing to specific genomic regions and loci. The biological functions of RdDM are not well studied in horticultural plants. Here, we isolated the ethyl methane-sulfonate-induced mutant reduced organ size (ros) producing small leaves, flowers, and fruits in woodland strawberry (Fragaria vesca) due to reduced cell numbers compared with that in the wild-type (WT). The candidate mutation causes a premature stop codon in FvH4_6g28780, which shares high similarity to Arabidopsis (Arabidopsis thaliana) Factor of DNA Methylation1 (FDM1) encoding an RdDM pathway component and was named FveFDM1. Consistently, the fvefdm1CR mutants generated by CRISPR/Cas9 also produced smaller organs. Overexpressing FveFDM1 in an Arabidopsis fdm1-1 fdm2-1 double mutant restored DNA methylation at the RdDM target loci. FveFDM1 acts in a protein complex with its homolog Involved in De Novo 2 (FveIDN2). Furthermore, whole-genome bisulfite sequencing revealed that DNA methylation, especially in the CHH context, was remarkably reduced throughout the genome in fvefdm1. Common and specific differentially expressed genes were identified in different tissues of fvefdm1 compared to in WT tissues. DNA methylation and expression levels of several gibberellic acid (GA) biosynthesis and cell cycle genes were validated. Moreover, the contents of GA and auxin were substantially reduced in the young leaves of fvefdm1 compared to in the WT. However, exogenous application of GA and auxin could not recover the organ size of fvefdm1. In addition, expression levels of FveFDM1, FveIDN2, Nuclear RNA Polymerase D1 (FveNRPD1), Domains Rearranged Methylase 2 (FveDRM2), and cell cycle genes were greatly induced by GA treatment. Overall, our work demonstrated the critical roles of FveFDM1 in plant growth and development via RdDM-mediated DNA methylation in horticultural crops.
PMID: 36200851
Plant Physiol , IF:8.34 , 2023 Jan , V191 (1) : P542-557 doi: 10.1093/plphys/kiac447
Abscisic acid modulates neighbor proximity-induced leaf hyponasty in Arabidopsis.
Faculty of Biology and Medicine, Centre for Integrative Genomics, University of Lausanne, Genopode Building, Lausanne CH-1015, Switzerland.; Plant Biochemistry, Department of Biology, ETH Zurich, Universitat-Str. 2, CH-8092 Zurich, Switzerland.; Department of Plant Sciences, Downing Street, Cambridge, University of Cambridge, CB2 3EA, UK.
Leaves of shade-avoiding plants such as Arabidopsis (Arabidopsis thaliana) change their growth pattern and position in response to low red to far-red ratios (LRFRs) encountered in dense plant communities. Under LRFR, transcription factors of the phytochrome-interacting factor (PIF) family are derepressed. PIFs induce auxin production, which is required for promoting leaf hyponasty, thereby favoring access to unfiltered sunlight. Abscisic acid (ABA) has also been implicated in the control of leaf hyponasty, with gene expression patterns suggesting that LRFR regulates the ABA response. Here, we show that LRFR leads to a rapid increase in ABA levels in leaves. Changes in ABA levels depend on PIFs, which regulate the expression of genes encoding isoforms of the enzyme catalyzing a rate-limiting step in ABA biosynthesis. Interestingly, ABA biosynthesis and signaling mutants have more erect leaves than wild-type Arabidopsis under white light but respond less to LRFR. Consistent with this, ABA application decreases leaf angle under white light; however, this response is inhibited under LRFR. Tissue-specific interference with ABA signaling indicates that an ABA response is required in different cell types for LRFR-induced hyponasty. Collectively, our data indicate that LRFR triggers rapid PIF-mediated ABA production. ABA plays a different role in controlling hyponasty under white light than under LRFR. Moreover, ABA exerts its activity in multiple cell types to control leaf position.
PMID: 36135791
Plant Physiol , IF:8.34 , 2023 Jan , V191 (1) : P265-279 doi: 10.1093/plphys/kiac407
Abscisic acid inhibits primary root growth by impairing ABI4-mediated cell cycle and auxin biosynthesis.
School of Ecology and Environment, Northwestern Polytechnical University, Xi'an 710129, China.; College of Agronomy and Biotechnology, China Agricultural University, Beijing 100193, China.; Institute of Ecological Agriculture, Sichuan Agricultural University, Chengdu 611130, China.
Cell cycle progression and the phytohormones auxin and abscisic acid (ABA) play key roles in primary root growth, but how ABA mediates the transcription of cell cycle-related genes and the mechanism of crosstalk between ABA and auxin requires further research. Here, we report that ABA inhibits primary root growth by regulating the ABA INSENSITIVE4 (ABI4)-CYCLIN-DEPENDENT KINASE B2;2 (CDKB2;2)/CYCLIN B1;1 (CYCB1;1) module-mediated cell cycle as well as auxin biosynthesis in Arabidopsis (Arabidopsis thaliana). ABA induced ABI4 transcription in the primary root tip, and the abi4 mutant showed an ABA-insensitive phenotype in primary root growth. Compared with the wild type (WT), the meristem size and cell number of the primary root in abi4 increased in response to ABA. Further, the transcription levels of several cell-cycle positive regulator genes, including CDKB2;2 and CYCB1;1, were upregulated in abi4 primary root tips. Subsequent chromatin immunoprecipitation (ChIP)-seq, ChIP-qPCR, and biochemical analysis revealed that ABI4 repressed the expression of CDKB2;2 and CYCB1;1 by physically interacting with their promoters. Genetic analysis demonstrated that overexpression of CDKB2;2 or CYCB1;1 fully rescued the shorter primary root phenotype of ABI4-overexpression lines, and consistently, abi4/cdkb2;2-cr or abi4/cycb1;1-cr double mutations largely rescued the ABA-insensitive phenotype of abi4 with regard to primary root growth. The expression levels of DR5promoter-GFP and PIN1promoter::PIN1-GFP in abi4 primary root tips were significantly higher than those in WT after ABA treatment, with these changes being consistent with changes in auxin concentration and expression patterns of auxin biosynthesis genes. Taken together, these findings indicated that ABA inhibits primary root growth through ABI4-mediated cell cycle and auxin-related regulatory pathways.
PMID: 36047837
Environ Pollut , IF:8.071 , 2023 Jan , V322 : P121140 doi: 10.1016/j.envpol.2023.121140
Enhanced detoxification via Cyt-P450 governs cross-tolerance to ALS-inhibiting herbicides in weed species of Centaurea.
Agroforestry and Plant Biochemistry, Proteomics and Systems Biology, Department of Biochemistry and Molecular Biology, University of Cordoba, UCO-CeiA3, 14014, Cordoba, Spain.; Agroforestry and Plant Biochemistry, Proteomics and Systems Biology, Department of Biochemistry and Molecular Biology, University of Cordoba, UCO-CeiA3, 14014, Cordoba, Spain. Electronic address: z82vagaj@uco.es.; Biosciences Department, Polytechnic Institute of Beja, Beja, Portugal; VALORIZA-Research Centre for Endogenous Resource Valorization, Polytechnic Institute of Portalegre, Portalegre, Portugal.; Department of Agroforestry Sciences, Campus El Carmen, University of Huelva, 21007, Huelva, Spain.; Centro de Ciencias da Natureza, Campus Lagoa Do Sino, Universidade Federal de Sao Carlos, Buri, 18290-000, Brazil.; Plant Protection Department, Extremadura Scientific and Technological Research Center (CICYTEX), Ctra. de AV, Km 372, Badajoz, 06187, Guadajira, Spain.; Department D'Hortofructicultura, Botanica i Jardineria, Agrotecnio-CERCA Center, Universitat de Lleida, Lleida, Spain.
Centaurea is a genus of winter weeds with a similar life cycle and competitive traits, which occurs in small-grains production fields in the central-southern of the Iberian Peninsula. However, most of herbicides recommended for weed management in wheat show poor control of Centaurea species. This study summarizes the biology, herbicide tolerance to acetolactate synthase (ALS) inhibitors, and recommended chemical alternatives for the control of Centaurea species. Four species (C. cyanus L., C. diluta Aiton, C. melitensis L. and C. pullata L. subsp. baetica Talavera), taxonomically characterized, were found as the main important broadleaf weeds in small-grains production fields of the Iberian Peninsula. These species showed innate tolerance to tribenuron-methyl (TM), showing LD(50) values (mortality of 50% of a population) higher than the field dose of TM (20 g ai ha(-1)). The order of tolerance was C. diluta (LD(50) = 702 g ha(-1)) >> C. pullata (LD(50) = 180 g ha(-1)) >> C. cyanus (LD(50) = 65 g ha(-1)) > C. melitensis (LD(50) = 32 g ha(-1)). Centaurea cyanus and C. melitensis presented higher foliar retention (150-180 muL herbicide solution), absorption (14-28%) and subsequent translocation (7-12%) of TM with respect to the other two species. Centaurea spp. plants were able to metabolize (14)C-TM into non-toxic forms (hydroxylated OH-metsulfuron-methyl and conjugated-metsulfuron-methyl), with cytochrome P450 (Cyt-P450) monooxygenases being responsible for herbicide detoxification. Centaurea cyanus and C. mellitensis metabolized up to 25% of TM, while C. diluta and C. pullata metabolized more than 50% of the herbicide. Centaurea species showed 80-100% survival when treated with of florasulam, imazamox and/or metsulfuron-methyl, i.e., these weeds present cross-tolerance to ALS inhibitors. In contrast, auxin mimics herbicides (2,4-D, clopyralid, dicamba, fluroxypir and MCPA) efficiently controlled the four Centaurea species. In addition, the mixture of ALS-inhibitors and auxin mimics also proved to be an interesting alternative for the control of Centaurea. These results show that plants of the genus Centaurea found in the winter cereal fields of the Iberian Peninsula have an innate tolerance to TM and cross-resistance to other ALS-inhibiting herbicides, governed by reduced absorption and translocation, but mainly by the metabolization of the herbicide via Cyt-P450.
PMID: 36706859
Sci Total Environ , IF:7.963 , 2023 Jan , V855 : P158888 doi: 10.1016/j.scitotenv.2022.158888
Regulation of rhizospheric microbial network to enhance plant growth and resist pollutants: Unignorable weak electric field.
MOE Key Laboratory of Pollution Processes and Environmental Criteria, Tianjin Key Laboratory of Environmental Remediation and Pollution Control, College of Environmental Science and Engineering, Nankai University, No. 38 Tongyan Road, Jinnan District, Tianjin 300350, China.; College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China.; MOE Key Laboratory of Pollution Processes and Environmental Criteria, Tianjin Key Laboratory of Environmental Remediation and Pollution Control, College of Environmental Science and Engineering, Nankai University, No. 38 Tongyan Road, Jinnan District, Tianjin 300350, China. Electronic address: tianli1@nankai.edu.cn.
The union of Plant Growth-Promoting Bacteria (PGPB) and rhizosphere confers a series of functions beneficial to plant. However, the lack of an opearable in situ method limits the further understanding on the mechanism. In this study, a weak electric field was designed to regulate rhizospheric microflora in a constructed root-splitting reactor. Compared with the control, the aboveground and underground biomass of rice seedling increased by 17 % and 18 % (p < 0.05) respectively under the exist of weak electric field of 0.14 V/cm. The joint action of rhizosphere and PGPB displayed the detoxification ability in the condition of soluble petroleum hydrocarbons, where the height, stem diameter, biomass and root vigor of the plant was increased by 58 %, 32 %, 43 % and 48 % respectively than the control. The selective reproduction of endophytes and ectophytes (denitrifying, auxin-producing, hydrocarbon-degrading and electroactive bacteria) was observed under applied weak electric field, which enhanced the nitrogen utilization, cellular metabolic activity and resistance to toxic organics of plant. This was further confirmed by the up-regulated OTUs related to the hydrocarbon degradation function, tryptophan metabolism and metabolism of nicotinate and nicotinamide. Moreover, the weak electric field also enhanced the transfer ability of partial endophytes grown in the root to improve plant stress resistance. The results in this work inspired an exercisable method for in situ enrichment of PGPB in the rhizosphere to cope with food crisis and provided a new way to deal with sudden environmental events.
PMID: 36165908
mBio , IF:7.867 , 2023 Jan : Pe0336322 doi: 10.1128/mbio.03363-22
Emergence of an Auxin Sensing Domain in Plant-Associated Bacteria.
Laboratory of Crystallographic Studies, IACT (CSIC-UGR), Armilla, Spain.; Department of Biotechnology and Environmental Protection, Estacion Experimental del Zaidin, Consejo Superior de Investigaciones Cientificas, Granada, Spain.; Department of Biochemistry and Molecular Biology B and Immunology, Faculty of Chemistry, University of Murcia, Regional Campus of International Excellence Campus Mare Nostrum, Murcia, Spain.; Bioinformatics Research Center, Pavlov First Saint Petersburg Medical State University, St. Petersburg, Russia.; Molecular Biology Institute of Barcelona, CSIC, Barcelona, Spain.; The Center of Bio- and Chemoinformatics, I. M. Sechenov First Moscow State Medical University, Moscow, Russia.; Department of Microbiology, The Ohio State University, Columbus, Ohio, USA.
Bacteria have evolved a sophisticated array of signal transduction systems that allow them to adapt their physiology and metabolism to changing environmental conditions. Typically, these systems recognize signals through dedicated ligand binding domains (LBDs) to ultimately trigger a diversity of physiological responses. Nonetheless, an increasing number of reports reveal that signal transduction receptors also bind antagonists to inhibit responses mediated by agonists. The mechanisms by which antagonists block the downstream signaling cascade remain largely unknown. To advance our knowledge in this field, we used the LysR-type transcriptional regulator AdmX as a model. AdmX activates the expression of an antibiotic biosynthetic cluster in the rhizobacterium Serratia plymuthica. AdmX specifically recognizes the auxin phytohormone indole-3-acetic acid (IAA) and its biosynthetic intermediate indole-3-pyruvic acid (IPA) as signals. However, only IAA, but not IPA, was shown to regulate antibiotic production in S. plymuthica. Here, we report the high-resolution structures of the LBD of AdmX in complex with IAA and IPA. We found that IAA and IPA compete for binding to AdmX. Although IAA and IPA binding does not alter the oligomeric state of AdmX, IPA binding causes a higher degree of compactness in the protein structure. Molecular dynamics simulations revealed significant differences in the binding modes of IAA and IPA by AdmX, and the inspection of the three-dimensional structures evidenced differential agonist- and antagonist-mediated structural changes. Key residues for auxin binding were identified and an auxin recognition motif defined. Phylogenetic clustering supports the recent evolutionary emergence of this motif specifically in plant-associated enterobacteria. IMPORTANCE Although antagonists were found to bind different bacterial signal transduction receptors, we are still at the early stages of understanding the molecular details by which these molecules exert their inhibitory effects. Here, we provide insight into the structural changes resulting from the binding of an agonist and an antagonist to a sensor protein. Our data indicate that agonist and antagonist recognition is characterized by small conformational differences in the LBDs that can be efficiently transmitted to the output domain to modulate the final response. LBDs are subject to strong selective pressures and are rapidly evolving domains. An increasing number of reports support the idea that environmental factors drive the evolution of sensor domains. Given the recent evolutionary history of AdmX homologs, as well as their narrow phyletic distribution within plant-associated bacteria, our results are in accordance with a plant-mediated evolutionary process that resulted in the emergence of receptor proteins that specifically sense auxin phytohormones.
PMID: 36602305
Curr Opin Plant Biol , IF:7.834 , 2023 Jan , V73 : P102336 doi: 10.1016/j.pbi.2023.102336
Compounds from rhizosphere microbes that promote plant growth.
Instituto de Investigaciones Quimico-Biologicas, Universidad Michoacana de San Nicolas de Hidalgo. Edificio B3, Ciudad Universitaria, C. P. 58030, Morelia, Michoacan, Mexico.; Facultad de Quimico Farmacobiologia, Universidad Michoacana de San Nicolas de Hidalgo, C. P. 58240, Morelia, Michoacan, Mexico.; Instituto de Investigaciones Quimico-Biologicas, Universidad Michoacana de San Nicolas de Hidalgo. Edificio B3, Ciudad Universitaria, C. P. 58030, Morelia, Michoacan, Mexico. Electronic address: jbucio@umich.mx.
The rhizosphere is the soil-plant interface colonized by bacterial and fungal species that exert growth-promoting and adaptive benefits. The plant-bacteria relationships rely upon the perception of volatile organic compounds (VOCs), canonical phytohormones such as auxins and cytokinins, and the bacterial quorum sensing-related N-acyl-L-homoserine lactones and cyclodipeptides. On the other hand, plant-beneficial Trichoderma fungi emit highly active VOCs, including 6-pentyl-2H-pyran-2-one (6-PP), and beta-caryophyllene, which contribute to plant morphogenesis, but also into how these microbes spread over roots or live as endophytes. Here, we describe recent findings concerning how compounds from beneficial bacteria and fungi affect root architecture and advance into the signaling events that mediate microbial recognition.
PMID: 36716513
Food Chem , IF:7.514 , 2023 May , V408 : P135215 doi: 10.1016/j.foodchem.2022.135215
A multiomics integrative analysis of color de-synchronization with softening of 'Hass' avocado fruit: A first insight into a complex physiological disorder.
Escuela de Agronomia, Facultad de Ciencias Agronomicas y de los Alimentos, Pontificia Universidad Catolica de Valparaiso, Quillota, Chile.; KU Leuven, Facility for Systems Biology based Mass Spectrometry SYBIOMA, Leuven, Belgium; Biodiversity International, Biodiversity for Food and Agriculture, Leuven, Belgium.; Department of Analytical Chemistry, Faculty of Sciences, University of Granada, Granada, Spain.; Universidad Nacional Agraria La Molina, Instituto de Biotecnologia, Lima, Peru.; Centro de Estudios Postcosecha, Facultad de Ciencias Agronomicas, Universidad de Chile, Santiago, Chile.; Departamento de Fruticultura y Enologia, Facultad de Agronomia e Ingenieria Forestal, Pontificia Universidad Catolica de Chile, Santiago, Chile; Departamento de Genetica Molecular y Microbiologia, Facultad de Ciencias Biologicas, Pontificia Universidad Catolica de Chile, Santiago, Chile; ANID-Millennium Science Initiative Program - Millennium Nucleus for the Development of Super Adaptable Plants (MN-SAP), Santiago, Chile; Millennium Institute Center for Genome Regulation (CRG), Santiago, Chile. Electronic address: claudio.meneses@uc.cl.; Escuela de Agronomia, Facultad de Ciencias Agronomicas y de los Alimentos, Pontificia Universidad Catolica de Valparaiso, Quillota, Chile; Millennium Institute Center for Genome Regulation (CRG), Santiago, Chile. Electronic address: romina.pedreschi@pucv.cl.
Exocarp color de-synchronization with softening of 'Hass' avocado is a relevant recurrent problem for the avocado supply chain. This study aimed to unravel the mechanisms driving this de-synchronization integrating omics datasets from avocado exocarp of different storage conditions and color phenotypes. In addition, we propose potential biomarkers to predict color synchronized/de-synchronized fruit. Integration of transcriptomics, proteomics and metabolomics and network analysis revealed eight transcription factors associated with differentially regulated genes between regular air (RA) and controlled atmosphere (CA) and twelve transcription factors related to avocado fruit color de-synchronization control in ready-to-eat stage. CA was positively correlated to auxins, ethylene, cytokinins and brassinosteroids-related genes, while RA was characterized by enrichment of cell wall remodeling and abscisic acid content associated genes. At ready-to-eat higher contents of flavonoids, abscisic acid and brassinosteroids were associated with color-softening synchronized avocados. In contrast, de-synchronized fruit revealed increases of jasmonic acid, salicylic acid and auxin levels.
PMID: 36528992
Free Radic Biol Med , IF:7.376 , 2023 Feb , V196 : P93-107 doi: 10.1016/j.freeradbiomed.2023.01.015
Responses of individual and combined polystyrene and polymethyl methacrylate nanoplastics on hormonal content, fluorescence/photochemistry of chlorophylls and ROS scavenging capacity in Lemna minor under arsenic-induced oxidative stress.
Department of Molecular Biology and Genetics, Faculty of Science, Necmettin Erbakan University, Meram, 42090, Konya, Turkey. Electronic address: cozfidan@erbakan.edu.tr.; Department of Biotechnology, Faculty of Science, Selcuk University, Selcuklu, 42130, Konya, Turkey. Electronic address: eytugay@selcuk.edu.tr.; Department of Biotechnology, Faculty of Science, Selcuk University, Selcuklu, 42130, Konya, Turkey. Electronic address: busra.arikan@selcuk.edu.tr.; Department of Biotechnology, Faculty of Science, Selcuk University, Selcuklu, 42130, Konya, Turkey. Electronic address: fatmanur.alp@selcuk.edu.tr.; Department of Agricultural Trade and Management, Faculty of Economy and Administrative Sciences, Yeditepe University, 34755, Istanbul, Turkey. Electronic address: metinturan@yeditepe.edu.tr.; Department of Physics, Faculty of Science, Selcuk University, Selcuklu, 42130, Konya, Turkey. Electronic address: hcavusoglu@selcuk.edu.tr.; Graduate School of Natural and Applied Sciences, Nanotechnology and Advanced Materials, Selcuk University, Selcuklu, 42130, Konya, Turkey. Electronic address: huseyinsakalak@gmail.com.
Nanoplastics alter the adverse impacts of hazardous contaminants such as heavy metals by changing their adsorption and accumulation. Few findings are available on the interaction between nanoplastic and heavy metals in plants. However, there is no report on the mechanisms for removing metal stress-mediated oxidative damage by the combination treatments of nanoplastics. To address this lack of information, polystyrene nanoplastic (PS, 100 mg L(-1)) and polymethyl methacrylate (PMMA, 100 mg L(-1)) were hydroponically applied to Lemna minor exposed to arsenate (As, 100 muM) for 7 days. PS or PMMA caused a reduction in the contents of N, P, K, Ca, Mg and Mn, but the improved contents were detected in the presence of PS or PMMA plus As stress. The hormone contents (auxin, gibberellic acid, cytokinin, salicylic acid and jasmonic acid) reduced by stress were re-arranged through PS or PMMA applications. Based on chlorophyll efficiency, fluorescence kinetics and performance of PSII, the impaired photosynthesis by As stress was improved via PS or PMMA applications. This alleviation did not continue under the combined form of PS and PMMA in As-applied plants. All analyzed antioxidant activity (superoxide dismutase (SOD), catalase (CAT), peroxidase (POX), ascorbate peroxidase (APX), glutathione reductase (GR), glutathione S-transferase (GST), glutathione peroxidase (GPX), monodehydroascorbate reductase (MDHAR) and dehydroascorbate reductase (DHAR)) decreased or unchanged under As, PS or PMMA. Due to the inactivation of the defense system, L. minor had high levels of hydrogen peroxide (H(2)O(2)) and thiobarbituric acid reactive substances (TBARS), showing lipid peroxidation. After As toxicity, induvial applications of PS or PMMA indicated the activated enzyme capacity (SOD, POX, GST and GPX) and upregulated AsA/DHA, GSH/GSSG and redox state of GSH, which facilitated the removal of radical accumulation. The efficiency of the antioxidant system in As + PS + PMMA-applied L. minor was not enough to remove damage induced by As stress; hereby, TBARS and H(2)O(2) contents were similar to the As-treated group. Our findings from alone or combined application of PS and PMMA provide new information to advance the tolerance mechanism against As exposure in L. minor.
PMID: 36657731
Plant Cell Environ , IF:7.228 , 2023 Jan doi: 10.1111/pce.14548
Low light stress promotes new tiller regeneration by changing source-sink relationship and activating expression of expansin genes in wheat.
Key Laboratory of Agricultural Water Resources, Hebei Laboratory of Agricultural Water-Saving, Center for Agricultural Resources Research, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Shijiazhuang, China.; College of Advanced Agricultural Sciences, University of Chinese Academy of Sciences, Beijing, China.; Jilin Da'an Agro-ecosystem National Observation Research Station, Changchun Jingyuetan Remote Sensing Experiment Station, State Key Laboratory of Black Soils Conservation and Utilization, Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, Changchun, China.
Low light stress seriously decreased wheat grain number through the formation of aborted spike during the reproductive period and induced new tiller regeneration to offset the loss of grain number. However, the mechanism by which plants coordinate spike aborted growth and the regeneration of new tillers remains unknown. To better understand this coordinated process, morphological, physiological and transcriptomic analyses were performed under low light stress at the young microspore stage. Our findings indicated that leaves exhausted most stored carbohydrates in 1 day of darkness. However, spike and uppermost internode (UI) were converted from sink to source, due to increased abscisic acid (ABA) content and decreased cytokinin content. During this process, genes encoding amylases, Sugars Will Eventually be Exported Transporters (SWEET) and sucrose transporters or sucrose carriers (SUT/SUC) were upregulated in spike and UI, which degraded starch into soluble sugars and loaded them into the phloem. Subsequently, soluble sugars were transported to tiller node (TN) where cytokinin and auxin content increased and ABA content decreased, followed by unloading into TN cells by upregulated cell wall invertase (CWINV) genes and highly expressed H(+) /hexose symporter genes. Finally, expansin genes integrated the sugar pathway and hormone pathway, and regulate the formation of new tillers directly.
PMID: 36695201
Plant Cell Environ , IF:7.228 , 2023 Mar , V46 (3) : P975-990 doi: 10.1111/pce.14517
ZmBET5L1 inhibits primary root growth and decreases osmotic stress tolerance by mediating vesicle aggregation and tethering in maize.
National Key Laboratory of Crop Genetic Improvement, Hubei Hongshan Laboratory, Huazhong Agricultural University, Wuhan, China.; State Key Laboratory of Crop Biology, College of Life Science, Shandong Agricultural University, Shandong, Tai-An, China.; Key Laboratory of Plant Development and Environmental Adaption Biology, Ministry of Education, School of Life Sciences, Shandong University, Qingdao, China.
Improving osmotic stress tolerance is critical to help crops to thrive and maintain high yields in adverse environments. Here, we characterized a core subunit of the transport protein particle (TRAPP) complex, ZmBET5L1, in maize using knowledge-driven data mining and genome editing. We found that ZmBET5L1 can interact with TRAPP I complex subunits and act as a tethering factor to mediate vesicle aggregation and targeting from the endoplasmic reticulum to the Golgi apparatus. ZmBET5L1 knock-out increased the primary root elongation rate under 20% polyethylene glycol-simulated osmotic stress and the survival rate under drought stress compared to wild-type seedlings. In addition, we found that ZmBET5L1 moderates PIN1 polar localization and auxin flow to maintain normal root growth. ZmBET5L1 knock-out optimized auxin flow to the lateral side of the root and promoted its growth to generate a robust root, which may be related to improved osmotic stress tolerance. Together, these findings demonstrate that ZmBET5L1 inhibits primary root growth and decreases osmotic stress tolerance by regulating vesicle transport and auxin distribution. This study has improved our understanding of the role of tethering factors in response to abiotic stresses and identified desirable variants for breeding osmotic stress tolerance in maize.
PMID: 36515184
Plant Cell Environ , IF:7.228 , 2023 Mar , V46 (3) : P1018-1032 doi: 10.1111/pce.14508
Wheat genome architecture influences interactions with phytobeneficial microbial functional groups in the rhizosphere.
Univ Lyon, Universite Claude Bernard Lyon 1, CNRS, INRAE, VetAgro Sup, UMR5557 Ecologie Microbienne, Villeurbanne, France.; Genebank Department, Leibniz Institute of Plant Genetics and Crop Plant Research (IPK), Gatersleben, Germany.
Wheat has undergone a complex evolutionary history, which led to allopolyploidization and the hexaploid bread wheat Triticum aestivum. However, the significance of wheat genomic architecture for beneficial plant-microbe interactions is poorly understood, especially from a functional standpoint. In this study, we tested the hypothesis that wheat genomic architecture was an overriding factor determining root recruitment of microorganisms with particular plant-beneficial traits. We chose five wheat species representing genomic profiles AA (Triticum urartu), BB SS (Aegilops speltoides), DD (Aegilops tauschii), AABB (Triticum dicoccon) and AABBDD (Triticum aestivum) and assessed by quantitative polymerase chain reaction their ability to interact with free-nitrogen fixers, 1-aminocyclopropane-1-carboxylate deaminase producers, 2,4-diacetylphloroglucinol producers and auxin producers via the phenylpyruvate decarboxylase pathway, in combination with Illumina MiSeq metabarcoding analysis of N fixers (and of the total bacterial community). We found that the abundance of the microbial functional groups could fluctuate according to wheat genomic profile, as did the total bacterial abundance. N fixer diversity and total bacterial diversity were also influenced significantly by wheat genomic profile. Often, rather similar results were obtained for genomes DD (Ae. tauschii) and AABBDD (T. aestivum), pointing for the first time that the D genome could be particularly important for wheat-bacteria interactions.
PMID: 36494920
Plant Cell Environ , IF:7.228 , 2023 Feb , V46 (2) : P498-517 doi: 10.1111/pce.14491
ABA-responsive AREB1/ABI3-1/ABI5 cascade regulates IAA oxidase gene SlDAO2 to inhibit hypocotyl elongation in tomato.
Key Laboratory of Horticultural Crop Biology and Germplasm Innovation, Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Ministry of Agriculture, Beijing, People's Republic of China.; Crop Breeding and Cultivation Research Institute, Shanghai Academy of Agricultural Sciences, Shanghai, China.
Hypocotyl elongation is dramatically influenced by environmental factors and phytohormones. Indole-3-acetic acid (IAA) plays a prominent role in hypocotyl elongation, whereas abscisic acid (ABA) is regarded as an inhibitor through repressing IAA synthesis and signalling. However, the regulatory role of ABA in local IAA deactivation remains largely uncharacterized. In this study, we confirmed the antagonistic interplay of ABA and IAA during the hypocotyl elongation of tomato (Solanum lycopersicum) seedlings. We identified an IAA oxidase enzyme DIOXYGENASE FOR AUXIN OXIDATION2 (SlDAO2), and its expression was induced by both external and internal ABA signals in tomato hypocotyls. Moreover, the overexpression of SlDAO2 led to a reduced sensitivity to IAA, and the knockout of SlDAO2 alleviated the inhibitory effect of ABA on hypocotyl elongation. Furthermore, an ABA-responsive regulatory SlAREB1/SlABI3-1/SlABI5 cascade was identified to act upstream of SlDAO2 and to precisely control its expression. SlAREB1 directly bound to the ABRE present in the SlDAO2 promoter to activate SlDAO2 expression, and SlABI3-1 enhanced while SlABI5 inhibited the activation ability of SlAREB1 by directly interacting with SlAREB1. Our findings revealed that ABA might induce local IAA oxidation and deactivation via SlDAO2 to modulate IAA homoeostasis and thereby repress hypocotyl elongation in tomato.
PMID: 36369997
Plant Cell Environ , IF:7.228 , 2023 Feb , V46 (2) : P567-591 doi: 10.1111/pce.14486
Low iron ameliorates the salinity-induced growth cessation of seminal roots in wheat seedlings.
School of Agricultural Sciences, Zhengzhou University, Zhengzhou, China.; School of Life Sciences, Zhengzhou University, Zhengzhou, China.
Wheat plants are ubiquitously simultaneously exposed to salinity and limited iron availability caused by soil saline-alkalisation. Through this study, we found that both low Fe and NaCl severely inhibited the growth of seminal roots in wheat seedlings; however, sufficient Fe caused greater growth cessation of seminal roots than low Fe under salt stress. Low Fe improved the root meristematic division activity, not altering the mature cell sizes compared with sufficient Fe under salt stress. Foliar Fe spray and split-root experiments showed that low Fe-alleviating the salinity-induced growth cessation of seminal roots was dependent on local low Fe signals in the roots. Ionomics combined with TEM/X-ray few differences in the root Na(+) uptake and vacuolar Na(+) sequestration between two Fe levels under salt stress. Phytohormone profiling and metabolomics revealed salinity-induced overaccumulation of ACC/ethylene and tryptophan/auxin in the roots under sufficient Fe than under low Fe. Differential gene expression, pharmacological inhibitor addition and the root growth performance of transgenic wheat plants revealed that the rootward auxin efflux and was responsible for the low Fe-mediated amelioration of the salinity-induced growth cessation of seminal roots. Our findings will provide novel insights into the modulation of crop root growth under salt stress.
PMID: 36358019
Plant Cell Environ , IF:7.228 , 2023 Jan , V46 (1) : P306-321 doi: 10.1111/pce.14460
Integrated transcriptomic and metabolomic profiles reveal adaptive responses of three poplar varieties against the bacterial pathogen Lonsdalea populi.
National Engineering Research Center of Tree Breeding and Ecological Restoration, Key Laboratory of Genetics and Breeding in Forest Trees and Ornamental Plants, Ministry of Education, The Tree and Ornamental Plant Breeding and Biotechnology Laboratory of National Forestry and Grassland Administration, College of Biological Sciences and Biotechnology, Beijing Forestry University, Beijing, China.; Beijing Advanced Innovation Center for Tree Breeding by Molecular Design, Beijing Forestry University, Beijing, China.; The Key Laboratory for Silviculture and Conservation of Ministry of Education, College of Forestry, Beijing Forestry University, Beijing, China.
Different poplar varieties vary in their tolerance to certain pathogens. However, knowledge about molecular regulation and critical responses of resistant poplars during pathogen infection remains scarce. To investigate adaptive responses to canker disease caused by the bacterium Lonsdalea populi, we screened three poplar varieties with contrasting tolerance, including Populus deltoides. 'Zhonglin 2025' (2025), Populus x Euramericana. '74/76' (107) and Populus tomentosa cv 'henan' (P. tomentosa). Transcriptomic analysis revealed significant changes in the expression levels of defence-related genes in different poplar varieties in response to infection, which reshaped the PTI and ETI processes. Intriguingly, photosynthesis-related genes were found to be highly expressed in the resistant variety, whereas the opposite was observed in the susceptible variety. Susceptible poplars maintained the activation of defence-related genes during early period of onset, which restricted the expression of photosynthesis-related and auxin signal-related genes. Furthermore, combined with metabolomic analysis, differences in the content of antibacterial substances and key differentially expressed genes in phenylpropane and flavonoid biosynthesis pathways were identified. Delayed induction of catechin in the susceptible variety and it's in vitro antibacterial activity were considered to be one of the important reasons for the differences in resistance to L. populi compared with the resistant variety, which is of practical interest for tree breeding. Moreover, the trade-off between growth and defence observed among the three poplar varieties during infection provides new insights into the multilevel regulatory circuits in tree-pathogen interactions.
PMID: 36217265
Plant Cell Environ , IF:7.228 , 2023 Jan , V46 (1) : P215-238 doi: 10.1111/pce.14451
Impacts of iron on phosphate starvation-induced root hair growth in Arabidopsis.
State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, Nanjing, China and University of Chinese Academy of Sceinces, Beijing, China.; Co-Innovation Center for Sustainable Forestry in Southern China, College of Biology and the Environment, Nanjing Forestry University, Nanjing, China.
In Arabidopsis, phosphate starvation (-Pi)-induced responses of primary root and lateral root growth are documented to be correlated with ambient iron (Fe) status. However, whether and how Fe participates in -Pi-induced root hair growth (RHG) remains unclear. Here, responses of RHG to different Fe concentrations under Pi sufficiency/deficiency were verified. Generally, distinct dosage effects of Fe on RHG appeared at both Pi levels, due to the generation of reactive oxygen species. Following analyses using auxin mutants and the phr1 mutant revealed that auxin and the central regulator PHR1 are required for Fe-triggered RHG under -Pi. A further proteomic study indicated that processes of vesicle trafficking and auxin synthesis and transport were affected by Fe under -Pi, which were subsequently validated by using a vesicle trafficking inhibitor, brefeldin A, and an auxin reporter, R2D2. Moreover, vesicle trafficking-mediated recycling of PIN2, an auxin efflux transporter, was notably affected by Fe under -Pi. Correspondingly, root hairs of pin2 mutant displayed attenuated responses to Fe under -Pi. Together, we propose that Fe affects auxin signalling probably by modulating vesicle trafficking, chiefly the PIN2 recycling, which might work jointly with PHR1 on modulating -Pi-induced RHG.
PMID: 36174546
Microbiol Spectr , IF:7.171 , 2023 Feb : Pe0352522 doi: 10.1128/spectrum.03525-22
Root-Associated Antagonistic Pseudomonas spp. Contribute to Soil Suppressiveness against Banana Fusarium Wilt Disease of Banana.
Jiangsu Provincial Key Lab of Solid Organic Waste Utilization, Jiangsu Collaborative Innovation Center of Solid Organic Wastes, Educational Ministry Engineering Center of Resource-saving fertilizers, The Key Laboratory of Plant Immunity, Joint International Research Laboratory of Soil Health, Nanjing Agricultural University, Nanjing, Jiangsu, People's Republic of China.; The Sanya Institute of the Nanjing Agricultural University, Sanya, Hainan, People's Republic of China.
Members of the microbiotas colonizing the plant endophytic compartments and the surrounding bulk and rhizosphere soil play an important role in determining plant health. However, the relative contributions of the soil and endophytic microbiomes and their mechanistic roles in achieving disease suppression remain elusive. To disentangle the relative importance of the different microbiomes in the various plant compartments in inhibiting pathogen infection, we conducted a field experiment to track changes in the composition of microbial communities in bulk and rhizosphere soil and of root endophytes and leaf endosphere collected from bananas planted on Fusarium-infested orchards in disease-suppressive and disease-conducive soils. We found that the rhizosphere and roots were the two dominant plant parts whose bacterial communities contributed to pathogen suppression. We further observed that Pseudomonas was potentially a key organism acting as a pathogen antagonist, as illustrated by microbial community composition and network analysis. Subsequently, culturable pathogen-antagonistic Pseudomonas strains were isolated, and their potential suppressive functions or possible antibiosis in terms of auxin or siderophore synthesis and phosphate solubilization were screened to analyze the mode of action of candidate disease-suppressive Pseudomonas strains. In a follow-up in vivo and greenhouse experiment, we revealed that microbial consortia of culturable Pseudomonas strains P8 and S25 (or S36), isolated from banana plantlet rhizosphere and roots, respectively, significantly suppressed the survival of pathogens in the soil, manipulated the soil microbiome, and stimulated indigenous beneficial microbes. Overall, our study demonstrated that root-associated microbiomes, especially the antagonistic Pseudomonas sp. components, contribute markedly to soil suppression of banana Fusarium wilt. IMPORTANCE Soil suppression of Fusarium wilt disease has been proven to be linked with the local microbial community. However, the contribution of endophytic microbes to disease suppression in wilt-suppressive soils remains unclear. Moreover, the key microbes involving in Fusarium wilt-suppressive soils and in the endophytic populations have not been fully characterized. In this study, we demonstrate that root-associated microbes play vitally important roles in disease suppression. Root-associated Pseudomonas consortia were recognized as a key component in inhibiting pathogen abundance associated with the host banana plants. This finding is crucial to developing alternate strategies for soilborne disease management by harnessing the plant microbiome.
PMID: 36786644
Chemosphere , IF:7.086 , 2023 Feb , V313 : P137571 doi: 10.1016/j.chemosphere.2022.137571
Toxicity effects of nanoplastics on soybean (Glycine max L.): Mechanisms and transcriptomic analysis.
Key Laboratory of Wetland Ecology and Environment, State Key Laboratory of Black Soils Conservation and Utilization, Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, Changchun 130102, China.; Key Laboratory of Soybean Molecular Design Breeding, Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, Harbin 150081, China.; Engineering Research Center of Chinese Ministry of Education for Edible and Medicinal Fungi, Jilin Agricultural University, Changchun 130118, China. Electronic address: hanxuerong@jlau.edu.cn.; Key Laboratory of Wetland Ecology and Environment, State Key Laboratory of Black Soils Conservation and Utilization, Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, Changchun 130102, China. Electronic address: yuhw@iga.ac.cn.
Microplastic (MP) pollution has become a major concern in recent years. In agricultural production, MPs can not only affect the growth of crops but also affect yield. Compared with micron-sized MPs, nanoplastics (NPs) may be more harmful to plants. However, the effects of NPs on plant growth and development have attracted relatively little attention. As such, research has currently plateaued at the level of morphology and physiology, and the molecular mechanisms are still unclear. In this study, soybeans (Glycine max L.) were treated with polystyrene nanoplastics (PS-NPs) to observe phenotypic changes and measure the effects of PS-NPs on diverse aspects of soybeans. Compared to the control group, the soybean stem and root lengths were inhibited by 11.78% and 12.58%, respectively. The reactive oxygen species content and the antioxidant enzyme activities changed significantly (p < 0.05). The accumulation of manganese (Mn) and magnesium (Mg) in the roots revealed that root transmembrane transport was affected by PS-NPs stress. The content of salicylic acid 2-O-beta-glucoside was inhibited whereas the accumulation of l-tryptophan, the precursor of auxin synthesis, was significantly increased (p < 0.05) in leaves. Transcriptomic analysis showed that PS-NPs could affect soybean DNA repair, membrane protein transport, and hormone synthesis and response. This study revealed the toxicity of NPs to soybeans and that NPs affected a variety of biological processes through transcriptome and hormone metabolome analysis, which provides a theoretical basis to further study the molecular mechanism of the effects on plants.
PMID: 36535503
J Integr Plant Biol , IF:7.061 , 2023 Jan doi: 10.1111/jipb.13460
ESCRT-III component OsSNF7.2 modulates leaf rolling by trafficking and endosomal degradation of auxin biosynthetic enzyme OsYUC8 in rice.
State Key Laboratory for Crop Genetics and Germplasm Enhancement, Jiangsu Plant Gene Engineering Research Center, Nanjing Agricultural University, Nanjing, 210095, China.; Jiangsu Key Laboratory of Crop Genomics and Molecular Breeding/Key Laboratory of Plant Functional Genomics of the Ministry of Education/Jiangsu Key Laboratory of Crop Genetics and Physiology, Agricultural College of Yangzhou University, Yangzhou, 225009, China.; National Key Facility for Crop Gene Resources and Genetic Improvement, Institute of Crop Sciences, Chinese Academy of Agricultural Sciences, Beijing, 100081, China.
The endosomal sorting complex required for transport (ESCRT) is highly conserved in eukaryotic cells and plays an essential role in the biogenesis of multivesicular bodies and cargo degradation to the plant vacuole or lysosomes. Although ESCRT components affect a variety of plant growth and development processes, their impact on leaf development is rarely reported. Here, we found that OsSNF7.2, an ESCRT-III component, controls leaf rolling in rice (Oryza sativa). The Ossnf7.2 mutant rolled leaf 17 (rl17) has adaxially rolled leaves due to the decreased number and size of the bulliform cells. OsSNF7.2 is expressed ubiquitously in all tissues, and its protein is localized in the endosomal compartments. OsSNF7.2 homologs, including OsSNF7, OsSNF7.3, and OsSNF7.4, can physically interact with OsSNF7.2, but their single mutation did not result in leaf rolling. Other ESCRT complex subunits, namely OsVPS20, OsVPS24, and OsBRO1, also interact with OsSNF7.2. Further assays revealed that OsSNF7.2 interacts with OsYUC8 and aids its vacuolar degradation. Both Osyuc8 and rl17 Osyuc8 showed rolled leaves, indicating that OsYUC8 and OsSNF7.2 function in the same pathway, conferring leaf development. This study reveals a new biological function for the ESCRT-III components, and provides new insights into the molecular mechanisms underlying leaf rolling. This article is protected by copyright. All rights reserved.
PMID: 36702785
J Integr Plant Biol , IF:7.061 , 2023 Feb , V65 (2) : P324-342 doi: 10.1111/jipb.13441
To curve for survival: Apical hook development.
Department of Biology, School of Life Sciences, Key Laboratory of Molecular Design for Plant Cell Factory of Guangdong Higher Education Institutes, Institute of Plant and Food Science, Southern University of Science and Technology (SUSTech), Shenzhen, 518055, China.
Apical hook is a simple curved structure formed at the upper part of hypocotyls when dicot seeds germinate in darkness. The hook structure is transient but essential for seedlings' survival during soil emergence due to its efficient protection of the delicate shoot apex from mechanical injury. As a superb model system for studying plant differential growth, apical hook has fascinated botanists as early as the Darwin age, and significant advances have been achieved at both the morphological and molecular levels to understand how apical hook development is regulated. Here, we will mainly summarize the research progress at these two levels. We will also briefly compare the growth dynamics between apical hook and hypocotyl gravitropic bending at early seed germination phase, with the aim to deduce a certain consensus on their connections. Finally, we will outline the remaining questions and future research perspectives for apical hook development.
PMID: 36562414
J Integr Plant Biol , IF:7.061 , 2023 Jan , V65 (1) : P82-99 doi: 10.1111/jipb.13366
Transmembrane kinase 1-mediated auxin signal regulates membrane-associated clathrin in Arabidopsis roots.
Ministry of Education Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, 730000, China.; College of Life Sciences, Shaoxing University, Shaoxing, 312000, China.
Clathrin-mediated endocytosis (CME) is the major endocytic pathway in eukaryotic cells that directly regulates abundance of plasma membrane proteins. Clathrin triskelia are composed of clathrin heavy chains (CHCs) and light chains (CLCs), and the phytohormone auxin differentially regulates membrane-associated CLCs and CHCs, modulating the endocytosis and therefore the distribution of auxin efflux transporter PIN-FORMED2 (PIN2). However, the molecular mechanisms by which auxin regulates clathrin are still poorly understood. Transmembrane kinase (TMKs) family proteins are considered to contribute to auxin signaling and plant development; it remains unclear whether they are involved in PIN transport by CME. We assessed TMKs involvement in the regulation of clathrin by auxin, using genetic, pharmacological, and cytological approaches including live-cell imaging and immunofluorescence. In tmk1 mutant seedlings, auxin failed to rapidly regulate abundance of both CHC and CLC and to inhibit PIN2 endocytosis, leading to an impaired asymmetric distribution of PIN2 and therefore auxin. Furthermore, TMK3 and TMK4 were shown not to be involved in regulation of clathrin by auxin. In summary, TMK1 is essential for auxin-regulated clathrin recruitment and CME. TMK1 therefore plays a critical role in the establishment of an asymmetric distribution of PIN2 and an auxin gradient during root gravitropism.
PMID: 36114789
J Integr Plant Biol , IF:7.061 , 2023 Jan , V65 (1) : P25-44 doi: 10.1111/jipb.13365
Cowpea NAC1/NAC2 transcription factors improve growth and tolerance to drought and heat in transgenic cowpea through combined activation of photosynthetic and antioxidant mechanisms.
Department of Biosciences and Bioengineering, Indian Institute of Technology Guwahati, Guwahati, Assam, 781039, India.; Faculty of Applied Biological Sciences, Gifu University, 1-1, Yanagido, Gifu, 501-1193,, Japan.
NAC (NAM/ATAF1/2/CUC2) transcription factors are central switches of growth and stress responses in plants. However, unpredictable interspecies conservation of function and regulatory targets makes the well-studied NAC orthologs inapt for pulse engineering. The knowledge of suitable NAC candidates in hardy pulses like cowpea (Vigna unguiculata (L.) Walp.) is still in infancy, hence warrants immediate biotechnological intervention. Here, we showed that overexpression of two native NAC genes (VuNAC1 and VuNAC2) promoted germinative, vegetative, and reproductive growth and conferred multiple abiotic stress tolerance in a commercial cowpea variety. The transgenic lines displayed increased leaf area, thicker stem, nodule-rich denser root system, early flowering, higher pod production ( approximately 3.2-fold and approximately 2.1-fold), and greater seed weight (10.3% and 6.0%). In contrast, transient suppression of VuNAC1/2 caused severe growth retardation and flower inhibition. The overexpressor lines showed remarkable tolerance to major yield-declining terminal stresses, such as drought, salinity, heat, and cold, and recovered growth and seed production by boosting photosynthetic activity, water use efficiency, membrane integrity, Na(+) /K(+) homeostasis, and antioxidant activity. The comparative transcriptome study indicated consolidated activation of genes involved in chloroplast development, photosynthetic complexes, cell division and expansion, cell wall biogenesis, nutrient uptake and metabolism, stress response, abscisic acid, and auxin signaling. Unlike their orthologs, VuNAC1/2 direct synergistic transcriptional tuning of stress and developmental signaling to avoid unwanted trade-offs. Their overexpression governs the favorable interplay of photosynthesis and reactive oxygen species regulation to improve stress recovery, nutritional sufficiency, biomass, and production. This unconventional balance of strong stress tolerance and agronomic quality is useful for translational crop research and molecular breeding of pulses.
PMID: 36107155
J Exp Bot , IF:6.992 , 2023 Feb doi: 10.1093/jxb/erad058
The NIN-LIKE PROTEIN 7 (NLP7) transcription factor modulates auxin pathways to regulate root cap development.
Department of Botany and Plant Pathology and Center for Plant Biology, Purdue University, West Lafayette, IN.
The root cap is a small tissue located at the tip of the root with critical functions for root growth. Present in nearly all vascular plants, the root cap protects the root meristem, influences soil penetration, and perceives and transmits environmental signals that are critical for root branching patterns. To perform these functions, the root cap must remain a relatively stable size and must integrate endogenous developmental pathways with environmental signals, yet how it does so is not clear. We previously showed that low pH conditions alter root cap development, and these changes are mediated by the NIN LIKE PROTEIN 7 (NLP7) transcription factor, a master regulator of nitrate signaling. Here we show that NLP7 integrates nitrate signaling with auxin pathways to regulate root cap development. We find that low nitrate conditions promote aberrant release of root cap cells in Arabidopsis. Nitrate deficiency impacts auxin pathways in the last layer of the root cap, and this is mediated in part by NLP7. Mutations in NLP7 abolish the auxin minimum in the last layer of the root cap and alter root cap expression of the auxin carriers PIN-LIKES 3 (PILS3) and PIN-FORMED 7 (PIN7) as well as transcription factors that regulate PIN expression. Together, our data reveal NLP7 as a link between endogenous auxin pathways and nitrate signaling in the root cap.
PMID: 36787214
J Exp Bot , IF:6.992 , 2023 Feb doi: 10.1093/jxb/erad051
The wheat basic helix-loop-helix (bHLH) protein TabHLH123 positively regulates the formation of crown root and associates with plant height and 1000-grain weight in wheat under various conditions.
National Key Facility for Crop Gene Resources and Genetic Improvement/Institute of Crop Sciences, Chinese Academy of Agricultural Sciences, Beijing 100081, China.; College of Agronomy, Shanxi Agricultural University, Taigu 030031, China.
Crown roots are the main components of the fibrous root system in cereal crops and play critical roles in plant adaptation. However, the molecular mechanisms of crown root formation in wheat (Triticum aestivum L.) have not been fully elucidated. Here, we identified a wheat basic helix-loop-helix (bHLH) protein TabHLH123, which interacts with the essential regulator of crown root initiation, MORE ROOT in wheat (TaMOR). It is expressed highly in shoot bases and roots. Ectopic expression of TabHLH123 in rice exhibits more roots compared with wild type. TabHLH123 regulates the expression of genes controlling crown root development, auxin metabolism, response and transport. Moreover, we analyzed the nucleotide sequence polymorphisms of TabHLH123s in wheat genome. The superior haplotype of TabHLH123-6B with high root dry weight (RDW) and 1000-grain weight (TGW), and short plant height (PH) was identified. Our study highlights the role of TabHLH123 in regulating the crown root formation and puts a novel insight for molecular marker assisted breeding in wheat.
PMID: 36749713
J Exp Bot , IF:6.992 , 2023 Feb doi: 10.1093/jxb/erad048
Just enough fruit: understanding feedback mechanisms during sexual reproductive development.
Department of Fruit Tree Sciences, Institute of Plant Sciences, ARO, The Volcani Institute, Rishon Le'Zion 7528809, Israel.; School of Biology, Faculty of Biological Sciences, University of Leeds, Leeds.; The Robert H. Smith Faculty of Agriculture, Food and Environment, The Hebrew University of Jerusalem, Rehovot, 76100, Israel.
The fruit and seed produced by a small number of crop plants provide the majority of food eaten across the world. Given the growing global population, there is a pressing need to increase yields of these crops without using more land or more chemical inputs. Many of these crops display prominent 'fruit-flowering feedbacks', in which fruit produced early in sexual reproductive development can inhibit the production of further fruit by a range of mechanisms. Understanding and over-coming these feedbacks thus presents a plausible route to increasing crop yields 'for free'. In this review, we define three key types of fruit-flowering feedback, and examine how frequent they are, and their effects on reproduction in a wide range of both wild and cultivated species. We then assess how these phenomenologically distinct phenomena might arise from conserved phytohormonal signalling events, particularly the export of auxin from growing organs. Finally, we offer some thoughts on the evolutionary basis for these self-limiting sexual reproductive patterns, and whether they are also present in the cereal crops that fundamentally underpin global diets.
PMID: 36724082
J Exp Bot , IF:6.992 , 2023 Feb , V74 (3) : P743-754 doi: 10.1093/jxb/erac443
Phytohormones in plant responses to boron deficiency and toxicity.
International Research Centre for Environmental Membrane Biology & Department of Horticulture, Foshan University, Foshan 528000, China.; Tasmanian Institute of Agriculture, University of Tasmania, Hobart, TAS 7001, Australia.; Australian Research Council Centre of Excellence for Plant Success in Nature and Agriculture, School of Natural Sciences, University of Tasmania, Hobart, TAS 7001, Australia.; School of Biological Science, University of Western Australia, Crawley, WA 6009, Australia.
Boron (B) is an essential element for plant growth. Many agricultural soils around the globe have either insufficient or excessive amounts of available B, with major implications for crop production. Understanding major limitations imposed by B nutritional disorders may allow breeding crops for improved B use efficiency as well as make them more resilient to excessive B, thus reducing yield penalties. It has become apparent that B-related physiological disorders are mediated in large part by their impact on plant hormone production and signaling. The aim of this review is to summarize current knowledge of the roles of hormones in plant responses to B and their impact on plant growth and development. The most significant effect of B deficiency is the inhibition of root elongation. Boron deficiency promotes the redistribution of auxin in the root elongation zone. Together with cytokinin signals and ethylene, this redistribution and modulation of auxin content triggers inhibition of the root cell elongation. Under B deficiency, root development is also regulated by brassinosteroids and jasmonic acid. Excess B can induce the production of reactive oxygen species (ROS). Abscisic acid and salicylic acid are both produced in response to B toxicity, and both can induce the antioxidant defense system to detoxify ROS. Another adaptation to B toxicity involves changes in the expression levels and activity of aquaporins in roots, thus reducing the uptake of water and delivery of B into the transpiration stream. In addition, abscisic acid mediates stomatal closure to further limit transpiration and the consequent accumulation of B in leaves.
PMID: 36398724
J Exp Bot , IF:6.992 , 2023 Feb , V74 (4) : P1176-1185 doi: 10.1093/jxb/erac441
Jasmonate-regulated root growth inhibition and root hair elongation.
CAS Key Laboratory of Tropical Plant Resources and Sustainable Use, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Kunming, Yunnan 650223, China.; Center of Economic Botany, Core Botanical Gardens, Chinese Academy of Sciences, Kunming, Yunnan 650223, China.; University of Chinese Academy of Sciences, Beijing 100049, China.; State Key Laboratory for Conservation and Utilization of Bio-Resources in Yunnan, School of Life Sciences, Yunnan University, Kunming, Yunnan 650091, China.
The phytohormone jasmonate is an essential endogenous signal in the regulation of multiple plant processes for environmental adaptation, such as primary root growth inhibition and root hair elongation. Perception of environmental stresses promotes the accumulation of jasmonate, which is sensed by the CORONATINE INSENSITIVE1 (COI1)-JASMONATE ZIM-DOMAIN (JAZ) co-receptor, triggering the degradation of JAZ repressors and induction of transcriptional reprogramming. The basic helix-loop-helix (bHLH) subgroup IIIe transcription factors MYC2, MYC3, and MYC4 are the most extensively characterized JAZ-binding factors and together stimulate jasmonate-signaled primary root growth inhibition. Conversely, the bHLH subgroup IIId transcription factors (i.e. bHLH3 and bHLH17) physically associate with JAZ proteins and suppress jasmonate-induced root growth inhibition. For root hair development, JAZ proteins interact with and inhibit ROOT HAIR DEFECTIVE 6 (RHD6) and RHD6 LIKE1 (RSL1) transcription factors to modulate jasmonate-enhanced root hair elongation. Moreover, jasmonate also interacts with other signaling pathways (such as ethylene and auxin) to regulate primary root growth and/or root hair elongation. Here, we review recent progress into jasmonate-mediated primary root growth and root hair development.
PMID: 36346644
J Exp Bot , IF:6.992 , 2023 Feb , V74 (3) : P931-944 doi: 10.1093/jxb/erac430
The locoweed endophyte Alternaria oxytropis affects root development in Arabidopsis in vitro through auxin signaling and polar transport.
Key Laboratory of Resource Biology and Biotechnology in Western China, Ministry of Education, College of Life Sciences, Northwest University, Xi'an 710069, China.; Qinling National Botanical Garden, Xi'an 710404, China.; Shaanxi Institute for Food and Drug Control, Xi'an 710065, China.; Provincial Key Laboratory of Biotechnology of Shaanxi Province, College of Life Sciences, Northwest University, Xi'an 710069, China.; National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan 430070, China.; Hubei Hongshan Laboratory, Wuhan 430070, China.; Institute of Biology, Environmental and Rural Sciences, Aberystwyth University, Aberystwyth SY23 3FL, UK.; Key Laboratory of Grassland Resources of Ministry of Education, College of Grassland, Resources and Environment, Inner Mongolia Agricultural University, Hohhot 010018, China.
Locoweeds are leguminous forbs known for their toxicity to livestock caused by the endophytic fungi Alternaria sect. Undifilum. Unlike the defensive mutualisms reported in many toxin-producing endophytes and their plant hosts, the benefits that A. sect. Undifilum can confer to it host plants remains unclear. Here, we conducted physiological and genetic analyses to show that A. (sect. Undifilum) oxytropis influences growth, especially root development, in its locoweed host Oxytropis ochrocephala and Arabidopsis. The presence of A. oxytropis significantly decreased primary root length while increasing the numbers of lateral roots and root hairs, and increasing plant leaf area and fresh weight. The fungus also increased the concentrations of plant endogenous auxin, and the expression of key genes for auxin biosynthesis, signaling, and transport. These effects on root development were abolished in mutants deficient in auxin signaling and polar transport. Alternaria oxytropis down-regulated expression of PIN1 but increased expression of PIN2, PIN7, and AUX1, which might reflect alterations in the spatial accumulation of auxin responsible for the changes in root architecture. Plant growth was insensitive to A. oxytropis when naphthylphthalamic acid was applied. Our findings indicate a function of A. oxytropis in promoting the growth and development of Arabidopsis via the regulation of auxin, which in turn suggests a possible role in benefiting its locoweed hosts via a process independent of its toxin production.
PMID: 36306203
J Exp Bot , IF:6.992 , 2023 Jan , V74 (1) : P364-376 doi: 10.1093/jxb/erac421
Metabolic link between auxin production and specialized metabolites in Sorghum bicolor.
Plant Molecular and Cellular Biology Program, University of Florida, Gainesville, FL 32611, USA.; Horticultural Sciences Department, University of Florida, Gainesville, FL 32611, USA.; Department of Chemistry, University of Florida, Gainesville, FL 32611, USA.; Chemistry Research Unit, Center for Medical, Agricultural and Veterinary Entomology, U.S. Department of Agriculture-Agricultural Research Service, Gainesville, FL 32608, USA.; Department of Microbiology & Cell Science, Gainesville, FL 32611, USA.; UF Genetics Institute, University of Florida, Gainesville, FL 32611, USA.; Florida Center for Renewable Chemicals and Fuels, University of Florida, Gainesville, FL 32611, USA.
Aldoximes are amino acid derivatives that serve as intermediates for numerous specialized metabolites including cyanogenic glycosides, glucosinolates, and auxins. Aldoxime formation is mainly catalyzed by cytochrome P450 monooxygenases of the 79 family (CYP79s) that can have broad or narrow substrate specificity. Except for SbCYP79A1, aldoxime biosynthetic enzymes in the cereal sorghum (Sorghum bicolor) have not been characterized. This study identified nine CYP79-encoding genes in the genome of sorghum. A phylogenetic analysis of CYP79 showed that SbCYP79A61 formed a subclade with maize ZmCYP79A61, previously characterized to be involved in aldoxime biosynthesis. Functional characterization of this sorghum enzyme using transient expression in Nicotiana benthamiana and stable overexpression in Arabidopsis thaliana revealed that SbCYP79A61 catalyzes the production of phenylacetaldoxime (PAOx) from phenylalanine but, unlike the maize enzyme, displays no detectable activity against tryptophan. Additionally, targeted metabolite analysis after stable isotope feeding assays revealed that PAOx can serve as a precursor of phenylacetic acid (PAA) in sorghum and identified benzyl cyanide as an intermediate of PAOx-derived PAA biosynthesis in both sorghum and maize. Taken together, our results demonstrate that SbCYP79A61 produces PAOx in sorghum and may serve in the biosynthesis of other nitrogen-containing phenylalanine-derived metabolites involved in mediating biotic and abiotic stresses.
PMID: 36300527
J Exp Bot , IF:6.992 , 2023 Jan , V74 (1) : P265-282 doi: 10.1093/jxb/erac416
GhROP6 GTPase modulates auxin accumulation in cotton fibers by regulating cell-specific GhPIN3a localization.
Biotechnology Research Center, Southwest University, No. 2 Tiansheng Road, Beibei, Chongqing, 400715, PR China.; Academy of Agricultural Sciences, Southwest University, Chongqing, PR China.; Chongqing Key Laboratory of Plant Resource Conservation and Germplasm Innovation, Southwest University, Chongqing, PR China.
PIN-FORMED- (PIN) mediated polar auxin transport plays a predominant role in most auxin-triggered organogenesis in plants. Global control of PIN polarity at the plasma membrane contributes to the essential establishment of auxin maxima in most multicellular tissues. However, establishment of auxin maxima in single cells is poorly understood. Cotton fibers, derived from ovule epidermal cells by auxin-triggered cell protrusion, provide an ideal model to explore the underlying mechanism. Here, we report that cell-specific degradation of GhPIN3a, which guides the establishment of the auxin gradient in cotton ovule epidermal cells, is associated with the preferential expression of GhROP6 GTPase in fiber cells. In turn, GhROP6 reduces GhPIN3a abundance at the plasma membrane and facilitates intracellular proteolysis of GhPIN3a. Overexpression and activation of GhROP6 promote cell elongation, resulting in a substantial improvement in cotton fiber length.
PMID: 36255218
J Exp Bot , IF:6.992 , 2023 Jan , V74 (1) : P233-250 doi: 10.1093/jxb/erac406
RsCLE22a regulates taproot growth through an auxin signaling-related pathway in radish (Raphanus sativus L.).
National Key Laboratory of Crop Genetics and Germplasm Enhancement, Key Laboratory of Horticultural Crop Biology and Genetic Improvement (East China) of MOAR, College of Horticulture, Nanjing Agricultural University, Nanjing 210095, China.; College of Horticulture and Landscape Architecture, Yangzhou University, Yangzhou 225009, China.
CLAVATA3/EMBRYO SURROUNDING REGION-related (CLE) peptides are a class of small molecules involved in plant growth and development. Although radish (Raphanus sativus) is an important root vegetable crop worldwide, the functions of CLE peptides in its taproot formation remain elusive. Here, a total of 48 RsCLE genes were identified from the radish genome. RNA in situ hybridization showed that RsCLE22a gene was highly expressed in the vascular cambium. Overexpression of RsCLE22a inhibited root growth by impairing stem cell proliferation in Arabidopsis, and radish plants with exogenous supplementation of RsCLE22 peptide (CLE22p) showed a similar phenotype. The vascular cambial activity was increased in RsCLE22a-silenced plants. Transcriptome analysis revealed that CLE22p altered the expression of several genes involved in meristem development and hormone signal transduction in radish. Immunolocalization results showed that CLE22p increased auxin accumulation in vascular cambium. Yeast one-hybrid and dual-luciferase assays showed that the WUSCHEL-RELATED HOMEOBOX 4 (RsWOX4) binds to RsCLE22a promoter and activates its transcription. The expression level of RsWOX4 was related to vascular cambial activity and was regulated by auxin. Furthermore, a RsCLE22a-RsWOX4 module is proposed to regulate taproot vascular cambium activity through an auxin signaling-related pathway in radish. These findings provide novel insights into the regulation of root growth in a horticultural crop.
PMID: 36239471
J Exp Bot , IF:6.992 , 2023 Feb , V74 (4) : P1186-1197 doi: 10.1093/jxb/erac251
Jasmonate action and crosstalk in flower development and fertility.
Plant Science and Technology College, Beijing University of Agriculture, Beijing, China.; Beijing Key Laboratory of Plant Gene Resources and Biotechnology for Carbon Reduction and Environmental Improvement, College of Life Sciences, Capital Normal University, Beijing, China.; Peking University Institute of Advanced Agricultural Sciences, Weifang, Shandong, China.; School of Life Sciences, Tsinghua University, Beijing, China.
Flower development and fertility are coordinately regulated by endogenous developmental signals, including the phytohormones jasmonates (JAs), auxin, and gibberellin, and environmental cues. JAs regulate stamen development and fertility under basal conditions, affect root growth and trichome formation under stress conditions, and control defense responses against insect herbivores and pathogens. Since the 1990s, an increasing number of studies have revealed the essential roles of JA biosynthesis, signaling, and crosstalk in regulation of flower development and fertility. Here, we summarize and present an updated overview of the JA pathway and its crosstalk in modulating flower/sexual organ development and fertility in Arabidopsis, tomato, rice, maize, and sorghum.
PMID: 35670512
J Exp Bot , IF:6.992 , 2023 Feb , V74 (4) : P1198-1206 doi: 10.1093/jxb/erab508
Roles of the wound hormone jasmonate in plant regeneration.
National Engineering Laboratory for Tree Breeding, College of Biological Sciences and Biotechnology, Beijing Forestry University, Beijing 100083, China.; Beijing Advanced Innovation Center for Tree Breeding by Molecular Design, Beijing Forestry University, Beijing 100083, China.; Institute of Tree Development and Genome Editing, Beijing Forestry University, Beijing 100083, China.; National Key Laboratory of Plant Molecular Genetics, CAS Center for Excellence in Molecular Plant Sciences, Institute of Plant Physiology and Ecology, Chinese Academy of Sciences, 300 Fenglin Road, Shanghai 200032, China.; University of Chinese Academy of Sciences, 19A Yuquan Road, Beijing 100049, China.; College of Life Sciences, Shanghai Normal University, Shanghai 200234, China.; State Key Laboratory of Plant Physiology and Biochemistry, College of Biological Sciences, China Agricultural University, Beijing 100193, China.
Plants have remarkable abilities to regenerate in response to wounding. How wounding triggers rapid signal transduction to induce a cellular response is a key topic for understanding the molecular mechanism of plant regeneration. An increasing body of evidence indicates that jasmonate, a hormone that is produced rapidly in response to wounding, plays multiple roles in different plant regeneration processes. In this review, we summarize recent advances on the roles of jasmonate in tissue repair, the formation of wound-induced callus, de novo organ regeneration, and somatic embryogenesis. Physiological and molecular analyses indicate that jasmonate can regulate stem cell activities, cell proliferation, cell fate transition, and auxin production, thereby contributing to plant regeneration. In addition, jasmonate is strictly controlled in plant cells via restriction of the jasmonate concentration and its signalling pathway in a spatial and temporal manner during regeneration. Overall, jasmonate acts as the hormone linking wounding to distinct types of regeneration in plants.
PMID: 34966932
Int J Biol Macromol , IF:6.953 , 2023 Feb , V234 : P123671 doi: 10.1016/j.ijbiomac.2023.123671
Phylogeny, transcriptional profile, and auxin-induced phosphorylation modification characteristics of conserved PIN proteins in Moso bamboo (Phyllostachys edulis).
Key Laboratory of National Forestry and Grassland Administration, Beijing for Bamboo & Rattan Science and Technology, International Center for Bamboo and Rattan, Beijing, China.; Key Laboratory of National Forestry and Grassland Administration, Beijing for Bamboo & Rattan Science and Technology, International Center for Bamboo and Rattan, Beijing, China. Electronic address: gaojianicbr@163.com.
Auxin polar transport is an important way for auxin to exercise its function, and auxin plays an irreplaceable role in the rapid growth of Moso bamboo. We identified and performed the structural analysis of PIN-FORMED auxin efflux carriers in Moso bamboo and obtained a total of 23 PhePIN genes from five gene subfamilies. We also performed chromosome localization and intra- and inter-species synthesis analysis. Phylogenetic analyses of 216 PIN genes showed that PIN genes are relatively conserved in the evolution of the Bambusoideae and have undergone intra-family segment replication in Moso bamboo. The PIN genes' transcriptional patterns showed that the PIN1 subfamily plays a major regulatory role. PIN genes and auxin biosynthesis maintain a high degree of consistency in spatial and temporal distribution. Phosphoproteomics analysis identified many phosphorylated protein kinases that respond to auxin regulation through autophosphorylation and phosphorylation of PIN proteins. The protein interaction network showed that there is a plant hormone interaction regulatory network with PIN protein as the core. We provide a comprehensive PIN protein analysis that complements the auxin regulatory pathway in Moso bamboo and paves the way for further auxin regulatory studies in bamboo.
PMID: 36801226
Int J Biol Macromol , IF:6.953 , 2023 Mar , V230 : P123165 doi: 10.1016/j.ijbiomac.2023.123165
Gnawing pressure led to the expansion of JAZ genes in angiosperms.
Key Laboratory of Plant Secondary Metabolism and Regulation of Zhejiang Province, College of Life Sciences and Medicine, Zhejiang Sci-Tech University, Hangzhou 310018, China; Institute of Soil and Water Conservation, Chinese Academy of Sciences & Ministry of Water Resource, Yangling 712100, China; University of the Chinese Academy of Sciences, Beijing 100049, China.; Key Laboratory of Plant Secondary Metabolism and Regulation of Zhejiang Province, College of Life Sciences and Medicine, Zhejiang Sci-Tech University, Hangzhou 310018, China.; Tasly R&D Institute, Tasly Holding Group Co. Ltd, Tianjin 300410, China; Tasly R&D Institute, State Key Laboratory of Core Technology in Innovative Chinese Medicine, Tianjin 300410, China.; Key Laboratory of Plant Secondary Metabolism and Regulation of Zhejiang Province, College of Life Sciences and Medicine, Zhejiang Sci-Tech University, Hangzhou 310018, China. Electronic address: xpg_xpg@zstu.edu.cn.; Key Laboratory of Plant Secondary Metabolism and Regulation of Zhejiang Province, College of Life Sciences and Medicine, Zhejiang Sci-Tech University, Hangzhou 310018, China; Institute of Soil and Water Conservation, Chinese Academy of Sciences & Ministry of Water Resource, Yangling 712100, China; University of the Chinese Academy of Sciences, Beijing 100049, China. Electronic address: liangzs@zstu.edu.cn.
A long-standing problem in evolutionary biology is why some populations differentiate into many species while the majority do not. Angiosperms is an excellent group for investigating this problem because their diversity is unevenly distributed in space and phylogeny. Plant hormone participates in growth, development and defense. However, jasmonic acid (JA) was the only hormone response to bites. We first searched jasmonate ZIM-domain (JAZ), AUXIN/INDOLE ACETIC ACID (IAA / aux), PYR/PYL/RCAR (PYL), DELLA, and SUPPRESSOR OF MAX2 1-like (SMAX) in 272 plant species. We found the gene number change trends were consistent with origination rates and species numbers of angiosperms. So, 26 representative species were selected as an example for further analysis. The results showed JAZ had experienced two lineage-specific gene expansion events in angiosperms, which coincided with increases in mammalian body size and dental diversity. The proliferation of large herbivores as a results of mammalian prosperity after dinosaur extinction may be related to angiosperm evolution and bursting. The proliferation of large herbivores as the result of mammalian prosperity after the extinction of the dinosaurs was related to angiosperm evolution and bursting. Overall, our study uncovered a previously unknown co-evolution mechanism in terrestrial plants exposed to extreme environmental conditions.
PMID: 36623623
Int J Biol Macromol , IF:6.953 , 2022 Dec , V232 : P123081 doi: 10.1016/j.ijbiomac.2022.12.300
Genome wide analysis of BREVIS RADIX gene family from wheat (Triticum aestivum): A conserved gene family differentially regulated by hormones and abiotic stresses.
ICAR-National Institute for Plant Biotechnology, Pusa Campus, New Delhi 110012, India; Amity Institute of Biotechnology, Amity University, Noida, Uttar Pradesh 201301, India.; ICAR-Central Tuber Crops Research Institute, Thiruvananthapuram, Kerala 695017, India.; Amity Institute of Biotechnology, Amity University, Noida, Uttar Pradesh 201301, India.; ICAR-National Institute for Plant Biotechnology, Pusa Campus, New Delhi 110012, India. Electronic address: Monika.Dalal@icar.gov.in.
BREVIS RADIX is a plant specific gene family with unique protein-protein interaction domain. It regulates developmental processes viz. root elongation and tiller angle which are pertinent for crop improvement. In the present study, five BRX family genes were identified in wheat genome and clustered into five sub-groups. Phylogenetic and synteny analyses revealed evolutionary conservation among BRX proteins from monocot species. Expression analyses showed abundance of TaBRXL1 transcripts in vegetative and reproductive tissues except flag leaf. TaBRXL2, TaBRXL3 and TaBRXL4 showed differential, tissue specific and lower level expression as compared to TaBRXL1. TaBRXL5-A expressed exclusively in stamens. TaBRXL1 was upregulated under biotic stresses while TaBRXL2 expression was enhanced under abiotic stresses. TaBRXL2 and TaBRXL3 were upregulated by ABA and IAA in roots. In shoot, TaBRXL2 was upregulated by ABA while TaBRXL3 and TaBRXL4 were upregulated by IAA. Expression levels, tissue specificity and response time under different conditions suggest distinct as well as overlapping functions of TaBRX genes. This was also evident from global co-expression network of these genes. Further, TaBRX proteins exhibited homotypic and heterotypic interactions which corroborated with the role of BRX domain in protein-protein interaction. This study provides leads for functional characterization of TaBRX genes.
PMID: 36592856
Int J Biol Macromol , IF:6.953 , 2023 Feb , V229 : P791-802 doi: 10.1016/j.ijbiomac.2022.12.230
Genome-wide identification and characterization of PIN-FORMED (PIN) and PIN-LIKES (PILS) gene family reveals their role in adventitious root development in tea nodal cutting (Camellia Sinensis).
International Institute of Tea Industry Innovation for "the Belt and Road", Nanjing Agricultural University, Nanjing 210095, Jiangsu, PR China.; College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing 210095, Jiangsu, PR China.; Department of Biotechnology, PSG College of Arts & Science, Coimbatore 14, Tamilnadu, India.; International Institute of Tea Industry Innovation for "the Belt and Road", Nanjing Agricultural University, Nanjing 210095, Jiangsu, PR China. Electronic address: lxh@njau.edu.cn.
Auxin affects all aspects of plant growth and development, including morphogenesis and adaptive responses. Auxin transmembrane transport is promoted by PIN formation (PIN) and a structurally similar PIN-like (PILS) gene family, which jointly controls the directional transport of the auxin between plant cells, and the accumulation of intracellular auxin. At present, there is no study investigating the roles of CslPIN and CslPILS gene family in root development in the tea plant (Camellia sinensis). In this study, 8 CslPIN and 10 CslPILS genes were identified in the tea plant, and their evolutionary relationships, physical and chemical properties, conserved motifs, cis-acting elements, chromosome location, collinearity, and expression characteristics were analyzed. The mechanism of CslPIN and CslPILS in the formation of tea adventitious roots (ARs) was studied by the AR induction system. Through functional verification, the regulation of CslPIN3 gene on root growth and development of tea plant was studied by over-expression of CslPIN3 in Arabidopsis thaliana and in situ hybridization in Camellia sinensis. The results confirmed CslPIN3 was involved in the regulation of root growth and development as well as auxin accumulation. This study provides a better insight into the regulatory mechanism of CslPIN and CslPILS gene family on the formation of AR in tea plant.
PMID: 36572081
Int J Biol Macromol , IF:6.953 , 2023 Feb , V227 : P285-296 doi: 10.1016/j.ijbiomac.2022.12.175
Genome-wide evolutionary analysis of AUX/IAA gene family in wheat identifies a novel gene TaIAA15-1A regulating flowering time by interacting with ARF.
College of Agronomy, Liaocheng University, Liaocheng 252059, PR China. Electronic address: pssu2014@163.com.; College of Agronomy, Liaocheng University, Liaocheng 252059, PR China.; Lianyungang Academy of Agricultural Sciences, Lianyungang 222000, PR China.; Key Laboratory of Huang-Huai-Hai Smart Agricultural Technology of the Ministry of Agriculture and Rural Affairs, College of Information Science and Engineering, Shandong Agricultural University, Tai'an, Shandong 271018, PR China. Electronic address: xinsinian2006@163.com.; College of Agronomy, Liaocheng University, Liaocheng 252059, PR China. Electronic address: guoshangjing@lcu.edu.cn.
Flowering time is a critical agronomic trait that has strong effects on crop yields. Auxin signaling pathway plays an important role in various development processes, such as flowering, grain development. However, no Aux/IAA gene had been reported to have functions involving in wheat flowering time. Here, we systematically performed genome-wide identification, classification, domain distribution, exon-intron structure, chromosome locations and global expression pattern of Aux/IAA gene family in 14 plant genomes (including Triticum aestivum). A phylogenetic model was proposed to infer the Aux/IAA evolutionary history involving in a central exon-intron structure "2121" during evolution. Overexpression of TaIAA15-1A caused an early flowering time in Brachypodium. RNA-seq analysis showed that TaIAA15-1A overexpression alters various pathways including phytohormone signaling pathway, flowering-related pathway, and polyamine biosynthesis pathway. Screening of auxin response factor (ARF) genes identified BdARF16 that interacted with TaIAA15-1A. Exogenous polyamine (spermidine and spermine) treatments promoted early flowering and (putrescine and DCHA) delayed flowering time of WT plants. Our finding will provide insights on mechanisms of Aux/IAAs gene family and TaIAA15-1A, illustrating the potential during crop improvement programs.
PMID: 36549029
Development , IF:6.868 , 2023 Feb doi: 10.1242/dev.200879
Developmental trajectory of pluripotent stem cell establishment in Arabidopsis callus guided by a quiescent center-related gene network.
National Key Laboratory of Plant Molecular Genetics, CAS Center for Excellence in Molecular Plant Sciences, Institute of Plant Physiology and Ecology, Chinese Academy of Sciences, 300 Fenglin Road, Shanghai 200032, China.; University of Chinese Academy of Sciences, 19A Yuquan Road, Beijing, 100049, China.
In plant tissue culture, callus is induced by a high auxin concentration. Among the three cell layers (the outer, middle, and inner cell layers) of callus, pluripotency acquisition in the middle cell layer is critical for the potential ability of callus to regenerate organs. Here, we reveal the developmental trajectory of middle cell layer initiation and maintenance in callus originating from Arabidopsis thaliana hypocotyls. The S phase in cell cycle is essential for the expression of quiescent center (QC)-related SCARECROW (SCR), PLETHORA1 (PLT1), and WUSCHEL-RELATED HOMEOBOX5 (WOX5) genes during the division of callus founder cells to initiate the callus primordium. After callus initiation, SHOOT-ROOT (SHR) proteins move from the inner to the middle cell layer and act together with SCR to promote the expression of PLT1 and WOX5. WOX5 represses the expression of VASCULAR-RELATED NAC-DOMAIN (VND) genes, thereby preventing callus from differentiating into the xylem. PLT1/2 directly activate JACKDAW (JKD) for pluripotency acquisition in the middle cell layer. We hypothesize that the middle cell layer could have pluripotent stem cell activity and its establishment requires the QC-related SCR-SHR-WOX5-PLT1/2-JKD gene network.
PMID: 36762604
Hortic Res , IF:6.793 , 2023 Feb , V10 (2) : Puhac267 doi: 10.1093/hr/uhac267
Theanine, a tea-plant-specific non-proteinogenic amino acid, is involved in the regulation of lateral root development in response to nitrogen status.
State Key Laboratory of Tea Plant Biology and Utilization, Anhui Agricultural University, Hefei 230036, China.; State Key Laboratory of Crop Genetics and Germplasm Enhancement, Nanjing Agricultural University, Nanjing 210095, China.
Glutamine synthetase type I (GSI)-like proteins are proposed to mediate nitrogen signaling and developmental fate by synthesizing yet unidentified metabolites. Theanine, the most abundant non-proteinogenic amino acid in tea plants, is the first identified metabolite synthesized by a GSI-like protein (CsTSI) in a living system. However, the roles of theanine in nitrogen signaling and development are little understood. In this study we found that nitrogen deficiency significantly reduced theanine accumulation and increased lateral root development in tea plant seedlings. Exogenous theanine feeding significantly repressed lateral root development of seedlings of tea plants and the model plant Arabidopsis. The transcriptomic analysis revealed that the differentially expressed genes in the roots under theanine feeding were enriched in the apoplastic pathway and H(2)O(2) metabolism. Consistently, theanine feeding reduced H(2)O(2) levels in the roots. Importantly, when co-treated with H(2)O(2), theanine abolished the promoting effect of H(2)O(2) on lateral root development in both tea plant and Arabidopsis seedlings. The results of histochemical assays confirmed that theanine inhibited reactive oxygen species accumulation in the roots. Further transcriptomic analyses suggested the expression of genes encoding enzymes involved in H(2)O(2) generation and scavenging was down- and upregulated by theanine, respectively. Moreover, the expression of genes involved in auxin metabolism and signaling, cell division, and cell expansion was also regulated by theanine. Collectively, these results suggested that CsTSI-synthesized theanine is likely involved in the regulation of lateral root development, via modulating H(2)O(2) accumulation, in response to nitrogen levels in tea plants. This study also implied that the module consisting of GSI-like protein and theanine-like metabolite is probably conserved in regulating development in response to nitrogen status in plant species.
PMID: 36778187
Hortic Res , IF:6.793 , 2023 Feb , V10 (2) : Puhac258 doi: 10.1093/hr/uhac258
Overexpression of miR390b promotes stem elongation and height growth in Populus.
Key Laboratory of Horticultural Plant Biology of Ministry of Education, College of Horticulture and Forestry Sciences, Huazhong Agricultural University, Wuhan 430070, China.; Poplar Research Center, Huazhong Agricultural University, Wuhan 430070, China.; Tobacco Research Institute, Chinese Academy of Agricultural Sciences, Qingdao 266101, China.
MicroRNA390 (miR390) is involved in plant growth and development by down-regulating the expression of the downstream genes trans-acting short interfering RNA3 (TAS3) and AUXIN RESPONSE FACTORs (ARFs). There is a scarcity of research on the involvement of the miR390-TAS3-ARFs pathway in the stem development of Populus. Here, differentially expressed miRNAs during poplar stem development were screened by small RNA sequencing analysis, and a novel function of miR390b in stem development was revealed. Overexpression of miR390b (OE-miR390b) resulted in a large increase in the number of xylem fiber cells and a slight decrease in the cell length at the longitudinal axis. Overall increases in stem elongation and plant height were observed in the OE-miR390b plants. According to transcriptome sequencing results and transient co-expression analysis, TAS3.1 and TAS3.2 were identified as the target genes of miR390 in poplar and were negatively regulated by miR390 in the apex. The transcription levels of ARF3.2 and ARF4 were significantly repressed in OE-miR390b plants and strongly negatively correlated with the number of xylem fiber cells along the longitudinal axis. These findings indicate that the conserved miR390-TAS3-ARFs pathway in poplar is involved in stem elongation and plant height growth.
PMID: 36778185
Cells , IF:6.6 , 2023 Jan , V12 (2) doi: 10.3390/cells12020295
The Histone H3K27 Demethylase REF6 Is a Positive Regulator of Light-Initiated Seed Germination in Arabidopsis.
Key Laboratory of South China Agricultural Plant Molecular Analysis and Genetic Improvement and Guangdong Provincial Key Laboratory of Applied Botany, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou 510650, China.; College of Life Sciences, University of Chinese Academy of Sciences, Beijing 100049, China.
Seed germination is the first step in initiating a new life cycle in seed plants. Light is a major environmental factor affecting seed germination. Phytochrome B (phyB) is the primary photoreceptor promoting germination during the initial phase of imbibition. Post-translational histone methylation occurring at both lysine and arginine residues plays a crucial role in transcriptional regulation in plants. However, the role of histone lysine demethylation in light-initiated seed germination is not yet reported. Here, we identified that Relative of Early Flowering 6 (REF6)/Jumonji Domain-containing Protein 12 (JMJ12), a histone H3 lysine 27 (H3K27) demethylase, acts as a positive regulator of light-initiated seed germination. The loss of function of REF6 in Arabidopsis inhibits phyB-dependent seed germination. Genome-wide RNA-sequencing analysis revealed that REF6 regulates about half of the light-responsive transcriptome in imbibed seeds, including genes related to multiple hormonal signaling pathways and cellular processes. Phenotypic analyses indicated that REF6 not only regulates seed germination through GA (gibberellin) and ABA (abscisic acid) processes but also depends on the auxin signaling pathway. Furthermore, REF6 directly binds to and decreases the histone H3K27me3 levels of auxin-signaling- and cell-wall-loosening-related genes, leading to the activated expression of these genes in imbibed seeds. Taken together, our study identifies REF6 as the first histone lysine demethylase required for light-initiated seed germination. Our work also reveals the important role of REF6-mediated histone H3K27 demethylation in transcriptional reprogramming in the light-initiated seed germination process.
PMID: 36672228
Plant J , IF:6.417 , 2023 Feb doi: 10.1111/tpj.16166
FaMYB123 interacts with FabHLH3 to regulate the late steps of anthocyanin and flavonol accumulation during ripening.
Department of Biochemistry and Molecular Biology, University of Cordoba, Edificio Severo Ochoa, Campus de Rabanales, E-14014, Cordoba, Spain.; Max-Planck-Institute of Molecular Plant Physiology, Am Muhlenberg 1, 14476 Potsdam-Golm, Germany.; Centro de Biotecnologia y Genomica de Plantas, Universidad Politecnica de Madrid (UPM) - Instituto Nacional de Investigacion y Tecnologia Agraria y Alimentaria (INIA-CSIC), Madrid, Spain.; Department of Agricultural Chemistry, University of Cordoba, Edificio Marie Curie, Campus de Rabanales, E-14014, Cordoba, Spain.; Instituto de Hortofruticultura Subtropical y Mediterranea La Mayora, Department of Plant Biology, University of Malaga, Campus de Teatinos, E-29071, Malaga, Spain.; Vascular Pathophysiology Area, Cardiovascular Proteomics Laboratory, Centro Nacional de Investigaciones Cardiovasculares Carlos III (CNIC), 28029, Madrid, Spain.; Department of Plant Biochemistry, Centre for Plant Molecular Biology (ZMBP), Eberhard Karls University, Tubingen, Germany.; Center of Plant Systems Biology and Biotechnology, Ruski Blvd. 139, Plovdiv, 4000, Bulgaria.
In this work, we identified and functionally characterized the R2R3 MYB transcription factor FaMYB123. As in most genes associated with organoleptic properties of ripe fruit, FaMYB123 expression is ripening-related, receptacle-specific, and antagonistically regulated by abscisic acid and auxin. Knockdown of FaMYB123 expression by RNAi in ripe strawberry fruit receptacles downregulated the expression of enzymes involved in the late steps of anthocyanin/flavonoid biosynthesis. Transgenic fruits showed a parallel decrease in total anthocyanin and flavonoid contents that were especially marked in malonyl derivatives of pelargonidin and cyanidins. The decrease was concomitant with accumulation of proanthocyanin, propelargonidins and other condensed tannins associated mainly with green receptacles. Potential coregulation between FaMYB123 and FaMYB10, which may act on different sets of genes for the enzymes involved in anthocyanin production, was explored. FaMYB123 and FabHLH3 were found to interact and to be involved in the transcriptional activation of FaMT1, a gene responsible for the malonylation of anthocyanin components during ripening. Taken together, these results demonstrate that FaMYB123 regulates the late steps of the flavonoid pathway in a specific manner. In this study, a new function for a R2R3-MYB TF, regulating the expression of a gene that encodes a malonyltransferase, has been elucidated.
PMID: 36840368
Plant J , IF:6.417 , 2023 Jan doi: 10.1111/tpj.16129
Boron supply restores aluminum-blocked auxin transport by the modulation of PIN2 trafficking in the root apical transition zone.
National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan, 430070, China.; International Research Center for Environmental Membrane Biology and Department of Horticulture, Foshan University, Foshan, 528000, China.; Microelement Research Center/Key Laboratory of Arable Land Conservation (Middle and Lower Reaches of Yangtze River), Ministry of Agriculture and Rural Affairs, Huazhong Agricultural University, Wuhan, 430070, China.; Institute of Cellular and Molecular Botany, University of Bonn, D-53115, Bonn, Germany.; State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Science, Nanjing, 210008, China.; Tasmanian Institute for Agriculture, College of Science and Engineering, University of Tasmania, Hobart, Tasmania, 7001, Australia.; School of Biological Sciences, University of Western Australia, Perth, 6009, Australia.
The supply of boron (B) alleviates the toxic effects of aluminum (Al) on root growth; however, the mechanistic basis of this process remains elusive. This study filled this knowledge gap, demonstrating that boron modifies auxin distribution and transport in Al-exposed Arabidopsis roots. In B-deprived roots, treatment with Al induced an increase in auxin content in the root apical meristem zone (MZ) and transition zone (TZ), whereas in the elongation zone (EZ) the auxin content was decreased beyond the level required for adequate growth. These distribution patterns are explained by the fact that basipetal auxin transport from the TZ to the EZ was disrupted by Al-inhibited PIN-FORMED 2 (PIN2) endocytosis. Experiments involving the modulation of protein biosynthesis by cycloheximide (CHX) and transcriptional regulation by cordycepin (COR) demonstrated that the Al-induced increase of PIN2 membrane proteins was dependent upon the inhibition of PIN2 endocytosis, rather than on the transcriptional regulation of the PIN2 gene. Experiments reporting on the profiling of Al(3+) and PIN2 proteins revealed that the inhibition of endocytosis of PIN2 proteins was the result of Al-induced limitation of the fluidity of the plasma membrane. The supply of B mediated the turnover of PIN2 endosomes conjugated with indole-3-acetic acid (IAA), and thus restored the Al-induced inhibition of IAA transport through the TZ to the EZ. Overall, the reported results demonstrate that boron supply mediates PIN2 endosome-based auxin transport to alleviate Al toxicity in plant roots.
PMID: 36721978
Plant J , IF:6.417 , 2023 Jan doi: 10.1111/tpj.16118
Role of reactive oxygen species in the modulation of auxin flux and root development in Arabidopsis thaliana.
Faculty of Biology, Institute of Biology II/Molecular Plant Physiology, University of Freiburg, 79104, Freiburg, Germany.; Instituto de Bioingenieria, Universidad Miguel Hernandez, 03202, Elche, Spain.; Centre for BioSystems Analysis, BIOSS Centre for Biological Signalling Studies, University of Freiburg, 79104, Freiburg, Germany.; State Key Laboratory of Crop Biology, College of Life Sciences, Shandong Agricultural University, Daizong Street 61, Tai'an, 271018, China.; ScreenSYS GmbH, Engesserstr. 4, Freiburg, 79108, Germany.
Reactive oxygen species (ROS) play a dual role in plant biology, acting as important signal transduction molecules and as toxic byproducts of aerobic metabolism that accumulate in cells upon exposure to different stressors and lead to cell death. In plants, root architecture is regulated by the distribution and intercellular flow of the phytohormone auxin. In this study, we identified ROS as an important modulator of auxin distribution and response in the root. ROS production is necessary for root growth, proper tissue patterning, cell growth, and lateral root (LR) induction. Alterations in ROS balance led to altered auxin distribution and response in SOD and RHD2 loss-of-function mutants. Treatment of Arabidopsis seedlings with additional sources of ROS (hydrogen peroxide) or an ROS production inhibitor (diphenylene iodonium) induced phenocopies of the mutants studied. Simultaneous application of auxin and ROS increased LR primordia induction, and PIN-FORMED protein immunolocalization further demonstrated the existing link between auxin and ROS in orchestrating cell division and auxin flux during root development. In Arabidopsis roots, genetic alterations in ROS balance led to defective auxin distribution and growth-related responses in roots. Exogenous hydrogen peroxide alters the establishment of the endogenous auxin gradient in the root meristem through regulation of PIN-FORMED polarity, while the simultaneous application of hydrogen peroxide and auxin enhanced LR induction in a dose- and position-dependent manner through activation of cell division.
PMID: 36700340
Plant J , IF:6.417 , 2023 Jan doi: 10.1111/tpj.16109
Biosynthesis- and transport-mediated dynamic auxin distribution during seed development controls seed size in Arabidopsis.
Tianjin Key Laboratory of Protein Sciences, Department of Plant Biology and Ecology, College of Life Sciences, Nankai University, Tianjin, 300071, China.
Auxin is indispensable to the fertilization-induced coordinated development of the embryo, endosperm, and seed coat. However, little attention has been given to the distribution pattern, maintenance mechanism, and function of auxin throughout the process of seed development. In the present study, we found that auxin response signals display a dynamic distribution pattern during Arabidopsis seed development. Shortly after fertilization, strong auxin response signals were observed at the funiculus, chalaza, and micropylar integument where the embryo attaches. Later, additional signals appeared at the middle layer of the inner integument (ii1') above the chalaza and the whole inner layer of the outer integument (oi1). These signals peaked when the seed was mature, then declined upon desiccation and disappeared in the dried seed. Auxin biosynthesis genes, including ASB1, TAA1, YUC1, YUC4, YUC8, and YUC9, contributed to the accumulation of auxin in the funiculus and seed coat. Auxin efflux carrier PIN3 and influx carrier AUX1 also contributed to the polar auxin distribution in the seed coat. PIN3 was expressed in the ii1 (innermost layer of the inner integument) and oi1 layers of the integument and showed polar localization. AUX1 was expressed in both layers of the outer integument and the endosperm and displayed a uniform localization. Further research demonstrated that the accumulation of auxin in the seed coat regulates seed size. Transgenic plants that specifically express the YUC8 gene in the oi2 or ii1 seed coat produced larger seeds. These results provide useful tools for cultivating high-yielding crops.
PMID: 36648165
Plant J , IF:6.417 , 2023 Jan doi: 10.1111/tpj.16103
CLE3 and its homologs share overlapping functions in the modulation of lateral root formation through CLV1 and BAM1 in Arabidopsis thaliana.
Graduate School of Science and Technology, Kumamoto University, Kumamoto, 860-8555, Japan.; Institute of Transformative Bio-Molecules, Nagoya University, Nagoya, 464-8601, Japan.; International Research Organization for Advanced Science and Technology (IROAST), Kumamoto University, Kumamoto, 860-8555, Japan.; International Research Center for Agriculture and Environmental Biology, Kumamoto University, Kumamoto, 860-8555, Japan.
Lateral roots are important for a wide range of processes, including uptake of water and nutrients. The CLAVATA3 (CLV3)/EMBRYO SURROUNDING REGION-RELATED (CLE) 1 ~ 7 peptide family and their cognate receptor CLV1 have been shown to negatively regulate lateral root formation under low-nitrate conditions. However, little is known about how CLE signaling regulates lateral root formation. A persistent obstacle in CLE peptide research is their functional redundancies, which makes functional analyses difficult. To address this problem, we generate the cle1 ~ 7 septuple mutant (cle1 ~ 7-cr1, cr stands for mutant allele generated with CRISPR/Cas9). cle1 ~ 7-cr1 exhibits longer lateral roots under normal conditions. Specifically, in cle1 ~ 7-cr1, the lateral root density is increased, and lateral root primordia initiation is found to be accelerated. Further analysis shows that cle3 single mutant exhibits slightly longer lateral roots. On the other hand, plants that overexpress CLE2 and CLE3 exhibit decreased lateral root lengths. To explore cognate receptor(s) of CLE2 and CLE3, we analyze lateral root lengths in clv1 barely any meristem 1(bam1) double mutant. Mutating both the CLV1 and BAM1 causes longer lateral roots, but not in each single mutant. In addition, genetic analysis reveals that CLV1 and BAM1 are epistatic to CLE2 and CLE3. Furthermore, gene expression analysis shows that the LATERAL ORGAN BOUNDARIES DOMAIN/ASYMMETRIC LEAVES2-LIKE (LBD/ASL) genes, which promote lateral root formation, are upregulated in cle1 ~ 7-cr1 and clv1 bam1. We therefore propose that CLE2 and CLE3 peptides are perceived by CLV1 and BAM1 to mediate lateral root formation through LBDs regulation.
PMID: 36628476
Plant J , IF:6.417 , 2023 Jan doi: 10.1111/tpj.16095
The Arabidopsis D27-LIKE1 is a cis/cis/trans-beta-carotene isomerase that contributes to Strigolactone biosynthesis and negatively impacts ABA level.
The BioActives Lab, Center for Desert Agriculture, King Abdullah University of Science and Technology, Thuwal, Jeddah, 23955, Saudi Arabia.; Plant Science Program, Biological and Environmental Science and Engineering Division, King Abdullah University of Science and Technology (KAUST), Thuwal, Jeddah, 23955, Saudi Arabia.; Department of Biology, Faculty of Applied Sciences, Umm Al-Qura University, 8XH2+XVP, Mecca, 24382, Saudi Arabia.; Agriculture and Agri-Food Canada, Kentville Research and Development Centre, 32 Main Street, Kentville, NS, B4N 1J5, Canada.; The Laboratory of Plant Cell and Developmental Biology, King Abdullah University of Science and Technology, Thuwal, Jeddah, 23955, Saudi Arabia.
The enzyme DWARF27 (D27) catalyzes the reversible isomerization of all-trans- into 9-cis-beta-carotene, initiating strigolactone (SL) biosynthesis. Genomes of higher plants encode two D27-homologs, D27-like1 and -like2, with unknown functions. Here, we investigated the enzymatic activity and biological function of the Arabidopsis D27-like1. In vitro enzymatic assays and expression in Synechocystis sp. PCC6803 revealed an unreported 13-cis/15-cis/9-cis- and a 9-cis/all-trans-beta-carotene isomerization. Although disruption of AtD27-like1 did not cause SL deficiency phenotypes, overexpression of AtD27-like1 in the d27 mutant restored the more-branching phenotype, indicating a contribution of AtD27-like1 to SL biosynthesis. Accordingly, generated d27 d27like1 double mutants showed a more pronounced branching phenotype compared to d27. The contribution of AtD27-like1 to SL biosynthesis is likely a result of its formation of 9-cis-beta-carotene that was present at higher levels in AtD27-like1 overexpressing lines. By contrast, AtD27-like1 expression correlated negatively with the content of 9-cis-violaxanthin, a precursor of ABA, in shoots. Consistently, ABA levels were higher in shoots and also in dry seeds of the d27like1 and d27 d27like1 mutants. Transgenic lines expressing GUS driven by the AtD27LIKE1 promoter and transcript analysis of hormone-treated Arabidopsis seedlings revealed that AtD27LIKE1 is expressed in different tissues and affects ABA and auxin. Taken together, our work reports a cis/cis-beta-carotene isomerase that affects the content of both cis-carotenoid-derived plant hormones, ABA and SLs.
PMID: 36602437
Plant J , IF:6.417 , 2023 Feb , V113 (4) : P851-865 doi: 10.1111/tpj.16089
The full-length Auxin Response Factor 8 isoform ARF8.1 controls pollen cell wall formation and directly regulates TDF1, AMS and MS188 expression.
Istituto di Biologia e Patologia Molecolari, Consiglio Nazionale delle Ricerche, Sapienza Universita di Roma, 00185, Rome, Italy.; Dipartimento di Biologia e Biotecnologie 'Charles Darwin', Sapienza Universita di Roma, 00185, Rome, Italy.; Centro de Energia Nuclear na Agricultura, Universidade de Sao Paulo, 13416-000, Piracicaba, Brazil.
Auxin Response Factor 8 plays a key role in late stamen development: its splice variants ARF8.4 and ARF8.2 control stamen elongation and anther dehiscence. Here, we characterized the role of ARF8 isoforms in pollen fertility. By phenotypic and ultrastructural analysis of arf8-7 mutant stamens, we found defects in pollen germination and viability caused by alterations in exine structure and pollen coat deposition. Furthermore, tapetum degeneration, a prerequisite for proper pollen wall formation, is delayed in arf8-7 anthers. In agreement, the genes encoding the transcription factors TDF1, AMS, MS188 and MS1, required for exine and pollen coat formation, and tapetum development, are downregulated in arf8-7 stamens. Consistently, the sporopollenin content is decreased, and the expression of sporopollenin synthesis/transport and pollen coat protein biosynthetic genes, regulated by AMS and MS188, is reduced. Inducible expression of the full-length isoform ARF8.1 in arf8-7 inflorescences complements the pollen (and tapetum) phenotype and restores the expression of the above transcription factors. Chromatin immunoprecipitation-quantitative polymerase chain reaction assay revealed that ARF8.1 directly targets the promoters of TDF1, AMS and MS188. In conclusion, the ARF8.1 isoform controls pollen and tapetum development acting directly on the expression of TDF1, AMS and MS188, which belong to the pollen/tapetum genetic pathway.
PMID: 36597651
Plant J , IF:6.417 , 2023 Jan doi: 10.1111/tpj.16093
Folate shapes plant root architecture by affecting auxin distribution.
Key Laboratory of Horticultural Plant Biology, MOE, and Key Laboratory of Horticultural Crop Biology and Genetic Improvement (Central Region), MOA, Huazhong Agricultural University, Wuhan, Hubei, 430070, China.; College of Horticulture, Henan Agricultural University, Zhengzhou, Henan, 450002, China.; Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Beijing, 100081, China.; College of Horticulture, Fujian Agriculture and Forestry University, Fuzhou, Fujian, 350002, China.
Folate (vitamin B9) is important for plant root development, but the mechanism is largely unknown. Here we characterized a root defective mutant, folb2, in Arabidopsis, which has severe developmental defects in the primary root. The root apical meristem of the folb2 mutant is impaired, and adventitious roots are frequently found at the root-hypocotyl junction. Positional cloning revealed that a 61-bp deletion is present in the predicted junction region of the promoter and the 5' untranslated region of AtFolB2, a gene encoding a dihydroneopterin aldolase that functions in folate biosynthesis. This mutation leads to a significant reduction in the transcript level of AtFolB2. Liquid chromatography-mass spectrometry analysis showed that the contents of the selected folate compounds were decreased in folb2. Arabidopsis AtFolB2 knockdown lines phenocopy the folb2 mutant. On the other hand, the application of exogenous 5-formyltetrahydrofolic acid could rescue the root phenotype of folb2, indicating that the root phenotype is indeed related to the folate level. Further analysis revealed that folate could promote rootward auxin transport through auxin transporters and that folate may affect particular auxin/indole-3-acetic acid proteins and auxin response factors. Our findings provide new insights into the important role of folic acid in shaping root structure.
PMID: 36587293
Plant J , IF:6.417 , 2023 Jan , V113 (2) : P225-245 doi: 10.1111/tpj.16042
A genome-wide association study identifies novel players in Na and Fe homeostasis in Arabidopsis thaliana under alkaline-salinity stress.
Plant Physiology Laboratory, Bioscience Faculty, Universitat Autonoma de Barcelona, C/de la Vall Moronta s/n, E-08193, Bellaterra, Spain.; Department of Botany and Plant Biology, University of Geneva, 1211, Geneva, Switzerland.; Laboratory of Genetics, Wageningen University and Research, Droevendaalsesteeg 1, 6708 PB, Wageningen, The Netherlands.
In nature, multiple stress factors occur simultaneously. The screening of natural diversity panels and subsequent Genome-Wide Association Studies (GWAS) is a powerful approach to identify genetic components of various stress responses. Here, the nutritional status variation of a set of 270 natural accessions of Arabidopsis thaliana grown on a natural saline-carbonated soil is evaluated. We report significant natural variation on leaf Na (LNa) and Fe (LFe) concentrations in the studied accessions. Allelic variation in the NINJA and YUC8 genes is associated with LNa diversity, and variation in the ALA3 is associated with LFe diversity. The allelic variation detected in these three genes leads to changes in their mRNA expression and correlates with plant differential growth performance when plants are exposed to alkaline salinity treatment under hydroponic conditions. We propose that YUC8 and NINJA expression patters regulate auxin and jasmonic signaling pathways affecting plant tolerance to alkaline salinity. Finally, we describe an impairment in growth and leaf Fe acquisition associated with differences in root expression of ALA3, encoding a phospholipid translocase active in plasma membrane and the trans Golgi network which directly interacts with proteins essential for the trafficking of PIN auxin transporters, reinforcing the role of phytohormonal processes in regulating ion homeostasis under alkaline salinity.
PMID: 36433704
Plant J , IF:6.417 , 2023 Jan , V113 (1) : P106-126 doi: 10.1111/tpj.16039
RAV1 mediates cytokinin signaling for regulating primary root growth in Arabidopsis.
Department of Biotechnology, St Xavier's College, 30, Mother Teresa Sarani, Kolkata, 700016, India.; Department of Mechanical Engineering, Indian Institute of Technology, Surjyamukhi Road, Amingaon, Guwahati, Assam, 781039, India.
Root growth dynamics is an outcome of complex hormonal crosstalk. The primary root meristem size, for example, is determined by antagonizing actions of cytokinin and auxin. Here we show that RAV1, a member of the AP2/ERF family of transcription factors, mediates cytokinin signaling in roots to regulate meristem size. The rav1 mutants have prominently longer primary roots, with a meristem that is significantly enlarged and contains higher cell numbers, compared with wild-type. The mutant phenotype could be restored on exogenous cytokinin application or by inhibiting auxin transport. At the transcript level, primary cytokinin-responsive genes like ARR1, ARR12 were significantly downregulated in the mutant root, indicating impaired cytokinin signaling. In concurrence, cytokinin induced regulation of SHY2, an Aux/IAA gene, and auxin efflux carrier PIN1 was hindered in rav1, leading to altered auxin transport and distribution. This effectively altered root meristem size in the mutant. Notably, CRF1, another member of the AP2/ERF family implicated in cytokinin signaling, is transcriptionally repressed by RAV1 to promote cytokinin response in roots. Further associating RAV1 with cytokinin signaling, our results demonstrate that cytokinin upregulates RAV1 expression through ARR1, during post-embryonic root development. Regulation of RAV1 expression is a part of secondary cytokinin response that eventually represses CRF1 to augment cytokinin signaling. To conclude, RAV1 functions in a branch pathway downstream to ARR1 that regulates CRF1 expression to enhance cytokinin action during primary root development in Arabidopsis.
PMID: 36423224
Plant J , IF:6.417 , 2023 Jan , V113 (1) : P92-105 doi: 10.1111/tpj.16036
CRISPR/Cas9 genome-editing applied to MdPGT1 in apple results in reduced foliar phloridzin without impacting plant growth.
Research and Innovation Centre, Edmund Mach Foundation, Via Edmund Mach 1, San Michele all'Adige, 38098, Italy.; C3A Center Agriculture Food Environment, University of Trento, Via Edmund Mach 1, San Michele all'Adige, 38098, Italy.; The New Zealand Institute for Plant and Food Research Limited, 120 Mt Albert Road, Auckland, 1025, New Zealand.; Research Group Plant Defense Physiology, Max Planck Institute for Chemical Ecology, Hans-Knoll-Strasse 8, Jena, 07745, Germany.; Laboratory of Growth Regulators, Institute of Experimental Botany, The Czech Academy of Sciences and Palacky University, Slechtitelu 19, Olomouc, CZ-783 71, Czech Republic.
Phloridzin is the most abundant polyphenolic compound in apple (Malus x domestica Borkh.), which results from the action of a key phloretin-specific UDP-2'-O-glucosyltransferase (MdPGT1). Here, we simultaneously assessed the effects of targeting MdPGT1 by conventional transgenesis and clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated protein 9 (Cas9)-mediated genome editing. To this end, we conducted transcriptomic and metabolic analyses of MdPGT1 RNA interference knockdown and genome-edited lines. Knockdown lines exhibited characteristic impairment of plant growth and leaf morphology, whereas genome-edited lines exhibited normal growth despite reduced foliar phloridzin. RNA-sequencing analysis identified a common core of regulated genes, involved in phenylpropanoid and flavonoid pathways. However, we identified genes and processes differentially modulated in stunted and genome-edited lines, including key transcription factors and genes involved in phytohormone signalling. Therefore, we conducted a phytohormone profiling to obtain insight into their role in the phenotypes observed. We found that salicylic and jasmonic acid were increased in dwarf lines, whereas auxin and ABA showed no correlation with the growth phenotype. Furthermore, bioactive brassinosteroids were commonly up-regulated, whereas gibberellin GA(4) was distinctively altered, showing a sharp decrease in RNA interference knockdown lines. Expression analysis by reverse transcriptase-quantitative polymerase chain reaction expression analysis further confirmed transcriptional regulation of key factors involved in brassinosteroid and gibberellin interaction. These findings suggest that a differential modulation of phytohormones may be involved in the contrasting effects on growth following phloridzin reduction. The present study also illustrates how CRISPR/Cas9 genome editing can be applied to dissect the contribution of genes involved in phloridzin biosynthesis in apple.
PMID: 36401738
Plant J , IF:6.417 , 2023 Jan , V113 (1) : P7-22 doi: 10.1111/tpj.16024
Endogenous auxin maintains embryonic cell identity and promotes somatic embryo development in Arabidopsis.
Plant Developmental Genetics, Institute of Biology Leiden, Leiden University, Sylviusweg 72, 2333 BE, Leiden, The Netherlands.; Bioscience, Wageningen University and Research, Droevendaalsesteeg 1, 6708 PB, Wageningen, The Netherlands.
Somatic embryogenesis (SE), or embryo development from in vitro cultured vegetative explants, can be induced in Arabidopsis by the synthetic auxin 2,4-dichlorophenoxyacetic acid (2,4-D) or by overexpression of specific transcription factors, such as AT-HOOK MOTIF NUCLEAR LOCALIZED 15 (AHL15). Here, we explored the role of endogenous auxin [indole-3-acetic acid (IAA)] during 2,4-D and AHL15-induced SE. Using the pWOX2:NLS-YFP reporter, we identified three distinct developmental stages for 2,4-D and AHL15-induced SE in Arabidopsis, with these being (i) acquisition of embryo identity; (ii) formation of pro-embryos; and (iii) somatic embryo patterning and development. The acquisition of embryo identity coincided with enhanced expression of the indole-3-pyruvic acid auxin biosynthesis YUCCA genes, resulting in an enhanced pDR5:GFP-reported auxin response in the embryo-forming tissues. Chemical inhibition of the indole-3-pyruvic acid pathway did not affect the acquisition of embryo identity, but significantly reduced or completely inhibited the formation of pro-embryos. Co-application of IAA with auxin biosynthesis inhibitors in the AHL15-induced SE system rescued differentiated somatic embryo formation, confirming that increased IAA levels are important during the last two stages of SE. Our analyses also showed that polar auxin transport, with AUXIN/LIKE-AUX influx and PIN-FORMED1 efflux carriers as important drivers, is required for the transition of embryonic cells to proembryos and, later, for correct cell fate specification and differentiation. Taken together, our results indicate that endogenous IAA biosynthesis and its polar transport are not required for the acquisition of embryo identity, but rather to maintain embryonic cell identity and for the formation of multicellular proembryos and their development into histodifferentiated embryos.
PMID: 36345646
Int J Mol Sci , IF:5.923 , 2023 Feb , V24 (4) doi: 10.3390/ijms24044190
Genomic Survey of Flavin Monooxygenases in Wild and Cultivated Rice Provides Insight into Evolution and Functional Diversities.
Plant Stress Biology Group, International Centre for Genetic Engineering and Biotechnology, New Delhi 110067, India.; Stress Physiology and Molecular Biology Laboratory, School of Life Sciences, Jawaharlal Nehru University, New Delhi 110067, India.
The flavin monooxygenase (FMO) enzyme was discovered in mammalian liver cells that convert a carcinogenic compound, N-N'-dimethylaniline, into a non-carcinogenic compound, N-oxide. Since then, many FMOs have been reported in animal systems for their primary role in the detoxification of xenobiotic compounds. In plants, this family has diverged to perform varied functions like pathogen defense, auxin biosynthesis, and S-oxygenation of compounds. Only a few members of this family, primarily those involved in auxin biosynthesis, have been functionally characterized in plant species. Thus, the present study aims to identify all the members of the FMO family in 10 different wild and cultivated Oryza species. Genome-wide analysis of the FMO family in different Oryza species reveals that each species has multiple FMO members in its genome and that this family is conserved throughout evolution. Taking clues from its role in pathogen defense and its possible function in ROS scavenging, we have also assessed the involvement of this family in abiotic stresses. A detailed in silico expression analysis of the FMO family in Oryza sativa subsp. japonica revealed that only a subset of genes responds to different abiotic stresses. This is supported by the experimental validation of a few selected genes using qRT-PCR in stress-sensitive Oryza sativa subsp. indica and stress-sensitive wild rice Oryza nivara. The identification and comprehensive in silico analysis of FMO genes from different Oryza species carried out in this study will serve as the foundation for further structural and functional studies of FMO genes in rice as well as other crop types.
PMID: 36835601
Int J Mol Sci , IF:5.923 , 2023 Feb , V24 (4) doi: 10.3390/ijms24044061
Comparison of Tomato Transcriptomic Profiles Reveals Overlapping Patterns in Abiotic and Biotic Stress Responses.
Department of Agricultural Science, University of Naples "Federico II," 80055 Portici, Italy.; Sequentia Biotech SL, Calle Comte D'Urgell 240, 08036 Barcelona, Spain.
Until a few years ago, many studies focused on the transcriptomic response to single stresses. However, tomato cultivations are often constrained by a wide range of biotic and abiotic stress that can occur singularly or in combination, and several genes can be involved in the defensive mechanism response. Therefore, we analyzed and compared the transcriptomic responses of resistant and susceptible genotypes to seven biotic stresses (Cladosporium fulvum, Phytophthora infestans, Pseudomonas syringae, Ralstonia solanacearum, Sclerotinia sclerotiorum, Tomato spotted wilt virus (TSWV) and Tuta absoluta) and five abiotic stresses (drought, salinity, low temperatures, and oxidative stress) to identify genes involved in response to multiple stressors. With this approach, we found genes encoding for TFs, phytohormones, or participating in signaling and cell wall metabolic processes, participating in defense against various biotic and abiotic stress. Moreover, a total of 1474 DEGs were commonly found between biotic and abiotic stress. Among these, 67 DEGs were involved in response to at least four different stresses. In particular, we found RLKs, MAPKs, Fasciclin-like arabinogalactans (FLAs), glycosyltransferases, genes involved in the auxin, ET, and JA pathways, MYBs, bZIPs, WRKYs and ERFs genes. Detected genes responsive to multiple stress might be further investigated with biotechnological approaches to effectively improve plant tolerance in the field.
PMID: 36835470
Int J Mol Sci , IF:5.923 , 2023 Feb , V24 (4) doi: 10.3390/ijms24043753
Paclobutrazol Promotes Root Development of Difficult-to-Root Plants by Coordinating Auxin and Abscisic Acid Signaling Pathways in Phoebe bournei.
School of Forestry, Central South University of Forestry and Technology, Changsha 410004, China.; Key Laboratory of Soil and Water Conservation and Desertification Combating of Hunan Province, Changsha 410004, China.; Department of Biology, East Carolina University, Greenville, NC 27858, USA.; School of Forestry, Henan Agricultural University, Zhengzhou 450002, China.
Phoebe bournei is a rare and endangered plant endemic to China with higher-value uses in essential oil and structural wood production. Its seedlings are prone to death because of its undeveloped system. Paclobutrazol (PBZ) can improve root growth and development in certain plants, but its concentration effect and molecular mechanism remain unclear. Here, we studied the physiological and molecular mechanisms by which PBZ regulates root growth under different treatments. We found that, with moderate concentration treatment (MT), PBZ significantly increased the total root length (69.90%), root surface area (56.35%), and lateral root number (47.17%). IAA content was the highest at MT and was 3.83, 1.86, and 2.47 times greater than the control, low, and high-concentration treatments. In comparison, ABA content was the lowest and reduced by 63.89%, 30.84%, and 44.79%, respectively. The number of upregulated differentially expressed genes (DEGs) induced at MT was more than that of down-regulated DEGs, which enriched 8022 DEGs in response to PBZ treatments. WGCNA showed that PBZ-responsive genes were significantly correlated with plant hormone content and involved in plant hormone signal transduction and MAPK signal pathway-plant pathways, which controls root growth. The hub genes are observably associated with auxin, abscisic acid syntheses, and signaling pathways, such as PINs, ABCBs, TARs, ARFs, LBDs, and PYLs. We constructed a model which showed PBZ treatments mediated the antagonism interaction of IAA and ABA to regulate the root growth in P. bournei. Our result provides new insights and molecular strategies for solving rare plants' root growth problems.
PMID: 36835160
Int J Mol Sci , IF:5.923 , 2023 Feb , V24 (4) doi: 10.3390/ijms24043631
Insights on Phytohormonal Crosstalk in Plant Response to Nitrogen Stress: A Focus on Plant Root Growth and Development.
State Key Laboratory of Conservation and Utilization of Subtropical Agro-Bioresources, Guangxi Key Laboratory of Sugarcane Biology, Guangxi University, Nanning 530004, China.; Department of Horticulture, Institute of Vegetable Science, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou 310058, China.; National Demonstration Center for Experimental Plant Science Education, College of Agriculture, Guangxi University, Nanning 530004, China.
Nitrogen (N) is a vital mineral component that can restrict the growth and development of plants if supplied inappropriately. In order to benefit their growth and development, plants have complex physiological and structural responses to changes in their nitrogen supply. As higher plants have multiple organs with varying functions and nutritional requirements, they coordinate their responses at the whole-plant level based on local and long-distance signaling pathways. It has been suggested that phytohormones are signaling substances in such pathways. The nitrogen signaling pathway is closely associated with phytohormones such as auxin (AUX), abscisic acid (ABA), cytokinins (CKs), ethylene (ETH), brassinosteroid (BR), strigolactones (SLs), jasmonic acid (JA), and salicylic acid (SA). Recent research has shed light on how nitrogen and phytohormones interact to modulate physiology and morphology. This review provides a summary of the research on how phytohormone signaling affects root system architecture (RSA) in response to nitrogen availability. Overall, this review contributes to identifying recent developments in the interaction between phytohormones and N, as well as serving as a foundation for further study.
PMID: 36835044
Int J Mol Sci , IF:5.923 , 2023 Feb , V24 (4) doi: 10.3390/ijms24043090
Do Opposites Attract? Auxin-Abscisic Acid Crosstalk: New Perspectives.
Centro de Biotecnologia y Genomica de Plantas, Instituto Nacional de Investigacion y Tecnologia Agraria y Alimentacion (INIA/CSIC), Universidad Politecnica de Madrid (UPM), Campus de Montegancedo, Pozuelo de Alarcon, 28223 Madrid, Spain.; Department of Evolutionary Biology, Ecology and Environmental Sciences, Faculty of Biology, University of Barcelona, 08028 Barcelona, Spain.; Departamento de Biotecnologia-Biologia Vegetal, Escuela Tecnica Superior de Ingenieria Agronomica, Alimentaria y de Biosistemas, Universidad Politecnica de Madrid (UPM), 28040 Madrid, Spain.
Plants are constantly exposed to a variety of different environmental stresses, including drought, salinity, and elevated temperatures. These stress cues are assumed to intensify in the future driven by the global climate change scenario which we are currently experiencing. These stressors have largely detrimental effects on plant growth and development and, therefore, put global food security in jeopardy. For this reason, it is necessary to expand our understanding of the underlying mechanisms by which plants respond to abiotic stresses. Especially boosting our insight into the ways by which plants balance their growth and their defense programs appear to be of paramount importance, as this may lead to novel perspectives that can pave the way to increase agricultural productivity in a sustainable manner. In this review, our aim was to present a detailed overview of different facets of the crosstalk between the antagonistic plant hormones abscisic acid (ABA) and auxin, two phytohormones that are the main drivers of plant stress responses, on the one hand, and plant growth, on the other.
PMID: 36834499
Int J Mol Sci , IF:5.923 , 2023 Feb , V24 (3) doi: 10.3390/ijms24032819
A Revised View of the LSU Gene Family: New Functions in Plant Stress Responses and Phytohormone Signaling.
Instituto de Bioquimica y Microbiologia, Facultad de Ciencias, Universidad Austral de Chile, Valdivia 5110566, Chile.; ANID-Millennium Science Initiative Program-Millennium Institute for Integrative Biology (iBio), Santiago 8331150, Chile.; Centro de Biotecnologia y Genomica de Plantas, INIA-CSIC-Universidad Politecnica de Madrid, 28223 Madrid, Spain.; Centro de Genomica y Bioinformatica, Facultad de Ciencias, Universidad Mayor, Santiago 8580745, Chile.; Escuela de Biotecnologia, Facultad de Ciencias, Universidad Mayor, Santiago 8580745, Chile.
LSUs (RESPONSE TO LOW SULFUR) are plant-specific proteins of unknown function that were initially identified during transcriptomic studies of the sulfur deficiency response in Arabidopsis. Recent functional studies have shown that LSUs are important hubs of protein interaction networks with potential roles in plant stress responses. In particular, LSU proteins have been reported to interact with members of the brassinosteroid, jasmonate signaling, and ethylene biosynthetic pathways, suggesting that LSUs may be involved in response to plant stress through modulation of phytohormones. Furthermore, in silico analysis of the promoter regions of LSU genes in Arabidopsis has revealed the presence of cis-regulatory elements that are potentially responsive to phytohormones such as ABA, auxin, and jasmonic acid, suggesting crosstalk between LSU proteins and phytohormones. In this review, we summarize current knowledge about the LSU gene family in plants and its potential role in phytohormone responses.
PMID: 36769138
Int J Mol Sci , IF:5.923 , 2023 Jan , V24 (3) doi: 10.3390/ijms24032566
A MYB Transcription Factor Atlas Provides Insights into the Evolution of Environmental Adaptations in Plants.
Key Laboratory of Quality and Safety Control for Subtropical Fruit and Vegetable, Ministry of Agriculture and Rural Affairs, College of Horticulture Science, Zhejiang A & F University, Hangzhou 311300, China.; College of Agriculture and Biotechnology, Zhejiang University, Hangzhou 310058, China.; Collaborative Innovation Center for Efficient and Green Production of Agriculture in Mountainous Areas of Zhejiang Province, College of Horticulture Science, Zhejiang A & F University, Hangzhou 311300, China.
The MYB transcription factor superfamily includes key regulators of plant development and responses to environmental changes. The diversity of lifestyles and morphological characteristics exhibited by plants are potentially associated with the genomic dynamics of the MYB superfamily. With the release of the plant genomes, a comprehensive phylogenomic analysis of the MYB superfamily across Viridiplantae is allowed. The present study performed phylogenetic, phylogenomic, syntenic, horizontal gene transfer, and neo/sub-functionalization analysis of the MYB superfamily to explore the evolutionary contributions of MYB members to species diversification, trait formation, and environmental adaptation in 437 different plant species. We identified major changes in copy number variation and genomic context within subclades across lineages. Multiple MYB subclades showed highly conserved copy number patterns and synteny across flowering plants, whereas others were more dynamic and showed lineage-specific patterns. As examples of lineage-specific morphological divergence, we hypothesize that the gain of a MYB orthogroup associated with flower development and environmental responses and an orthogroup associated with auxin and wax biosynthesis in angiosperms were correlated with the emergence of flowering plants, unbiased neo-/sub-functionalization of gene duplicates contributed to environmental adaptation, and species-specific neo-/sub-functionalization contributed to phenotype divergence between species. Transposable element insertion in promoter regions may have facilitated the sub-/neo-functionalization of MYB genes and likely played a tissue-specific role contributing to sub-/neo-functionalization in plant root tissues. This study provides new insights into the evolutionary divergence of the MYB superfamily across major flowering and non-flowering lineages and emphasizes the need for lineage-/tissue-specific characterization to further understand trait variability and environmental adaptation.
PMID: 36768888
Int J Mol Sci , IF:5.923 , 2023 Jan , V24 (3) doi: 10.3390/ijms24032414
Integrative Transcriptome, miRNAs, Degradome, and Phytohormone Analysis of Brassica rapa L. in Response to Plasmodiophora brassicae.
Institute of Horticulture, Henan Academy of Agricultural Sciences, Graduate T&R Base of Zhengzhou University, Zhengzhou 450002, China.; Henan International Joint Laboratory of Crop Gene Resources and Improvement, School of Agricultural Sciences, Zhengzhou University, Zhengzhou 450001, China.
Clubroot is an infectious root disease caused by Plasmodiophora brassicae in Brassica crops, which can cause immeasurable losses. We analyzed integrative transcriptome, small RNAs, degradome, and phytohormone comprehensively to explore the infection mechanism of P. brassicae. In this study, root samples of Brassica rapa resistant line material BrT24 (R-line) and susceptible line material Y510-9 (S-line) were collected at four different time points for cytological, transcriptome, miRNA, and degradome analyses. We found the critical period of disease resistance and infection were at 0-3 DAI (days after inoculation) and 9-20 DAI, respectively. Based on our finding, we further analyzed the data of 9 DAI vs. 20 DAI of S-line and predicted the key genes ARF8, NAC1, NAC4, TCP10, SPL14, REV, and AtHB, which were related to clubroot disease development and regulating disease resistance mechanisms. These genes are mainly related to auxin, cytokinin, jasmonic acid, and ethylene cycles. We proposed a regulatory model of plant hormones under the mRNA-miRNA regulation in the critical period of P. brassicae infection by using the present data of the integrative transcriptome, small RNAs, degradome, and phytohormone with our previously published results. Our integrative analysis provided new insights into the regulation relationship of miRNAs and plant hormones during the process of disease infection with P. brassicae.
PMID: 36768734
Int J Mol Sci , IF:5.923 , 2023 Jan , V24 (3) doi: 10.3390/ijms24032212
Comparative Transcriptome Analysis of the Heterosis of Salt Tolerance in Inter-Subspecific Hybrid Rice.
Institute of Crop and Nuclear Technology Utilization, Zhejiang Academy of Agricultural Sciences, Hangzhou 310021, China.; The Laboratory of Seed Science and Technology, Guangdong Key Laboratory of Plant Molecular Breeding, College of Agriculture, South China Agricultural University, Guangzhou 510642, China.
Soil salinity is one of the major abiotic stresses limiting rice growth. Hybrids outperform their parents in salt tolerance in rice, while its mechanism is not completely understood. In this study, a higher seedling survival was observed after salt treatment in an inter-subspecific hybrid rice, Zhegengyou1578 (ZGY1578), compared with its maternal japonica Zhegeng7A (ZG7A) and paternal indica Zhehui1578 (ZH1578). A total of 2584 and 3061 differentially expressed genes (DEGs) with at least twofold changes were identified between ZGY1578 and ZG7A and between ZGY1578 and ZH1578, respectively, in roots under salt stress using the RNA sequencing (RNA-Seq) approach. The expressions of a larger number of DEGs in hybrid were lower or higher than those of both parents. The DEGs associated with transcription factors, hormones, and reactive oxygen species (ROS)-related genes might be involved in the heterosis of salt tolerance. The expressions of the majority of transcription factors and ethylene-, auxin-, and gibberellin-related genes, as well as peroxidase genes, were significantly higher in the hybrid ZGY1578 compared with those of both parents. The identified genes provide valuable clues to elucidate the heterosis of salt tolerance in inter-subspecific hybrid rice.
PMID: 36768538
Int J Mol Sci , IF:5.923 , 2023 Jan , V24 (3) doi: 10.3390/ijms24032138
Genetic Variation, DIMBOA Accumulation, and Candidate Gene Identification in Maize Multiple Insect-Resistance.
State Key Laboratory of Aridland Crop Science, College of Agronomy, Gansu Agricultural University, Lanzhou 730070, China.; United States Department of Agriculture, Fargo, ND 58102-2765, USA.
Maize seedlings contain high amounts of 2,4-dihydroxy-7-methoxy-1,4-benzoxazin-3-one (DIMBOA), and the effect of DIMBOA is directly associated with multiple insect-resistance against insect pests such as Asian corn borer and corn leaf aphids. Although numerous genetic loci for multiple insect-resistant traits have been identified, little is known about genetic controls regarding DIMBOA content. In this study, the best linear unbiased prediction (BLUP) values of DIMBOA content in two ecological environments across 310 maize inbred lines were calculated; and their phenotypic data and BLUP values were used for marker-trait association analysis. We identified nine SSRs that were significantly associated with DIMBOA content, which explained 4.30-20.04% of the phenotypic variation. Combined with 47 original genetic loci from previous studies, we detected 19 hot loci and approximately 11 hot loci (in Bin 1.04, Bin 2.00-2.01, Bin 2.03-2.04, Bin 4.00-4.03, Bin 5.03, Bin 5.05-5.07, Bin 8.01-8.03, Bin 8.04-8.05, Bin 8.06, Bin 9.01, and Bin 10.04 regions) supported pleiotropy for their association with two or more insect-resistant traits. Within the 19 hot loci, we identified 49 candidate genes, including 12 controlling DIMBOA biosynthesis, 6 involved in sugar metabolism/homeostasis, 2 regulating peroxidases activity, 21 associated with growth and development [(auxin-upregulated RNAs (SAUR) family member and v-myb avian myeloblastosis viral oncogene homolog (MYB)], and 7 involved in several key enzyme activities (lipoxygenase, cysteine protease, restriction endonuclease, and ubiquitin-conjugating enzyme). The synergy and antagonism interactions among these genes formed the complex defense mechanisms induced by multiple insect pests. Moreover, sufficient genetic variation was reported for DIMBOA performance and SSR markers in the 310 tested maize inbred lines, and 3 highly (DIMBOA content was 402.74-528.88 mug g(-1) FW) and 15 moderate (DIMBOA content was 312.92-426.56 mug g(-1) FW) insect-resistant genotypes were major enriched in the Reid group. These insect-resistant inbred lines can be used as parents in maize breeding programs to develop new varieties.
PMID: 36768464
Int J Mol Sci , IF:5.923 , 2023 Jan , V24 (3) doi: 10.3390/ijms24032063
Influence of Light of Different Spectral Compositions on Growth Parameters, Photosynthetic Pigment Contents and Gene Expression in Scots Pine Plantlets.
K.A. Timiryazev Institute of Plant Physiology, Russian Academy of Sciences, Botanicheskaya Street 35, Moscow 127276, Russia.; Institute of Basic Biological Problems, Russian Academy of Sciences, Institutskaya Street 2, Pushchino 142290, Moscow Region, Russia.; Department of Plant Physiology, Biological Faculty, Lomonosov Moscow State University, Moscow 119991, Russia.
The photoreceptors of red light (phytochromes) and blue light (cryptochromes) impact plant growth and metabolism. However, their action has been barely studied, especially in coniferous plants. Therefore, the influence of blue (maximum 450 nm), red (maximum 660 nm), white light (maxima 450 nm + 575 nm), far-red light (maximum 730 nm), white fluorescent light and dark on seed germination, growth, chlorophyll and carotenoid contents, as well as the transcript levels of genes involved in reception, photosynthesis, light and hormonal signaling of Scots pine plantlets, was investigated. The highest values of dry weight, root length and photosynthetic pigment contents were characteristic of 9-day-old plantlets grown under red light, whereas in the dark plantlet length, seed vigor, seed germination, dry weight and pigment contents were decreased. Under blue and white lights, the main studied morphological parameters were decreased or close to red light. The cotyledons were undeveloped under dark conditions, likely due to the reduced content of photosynthetic pigments, which agrees with the low transcript levels of genes encoding protochlorophyllide oxidoreductase (PORA) and phytoene synthase (PSY). The transcript levels of a number of genes involved in phytohormone biosynthesis and signaling, such as GA3ox, RRa, KAO and JazA, were enhanced under red light, unlike under dark conditions. We suggest that the observed phenomena of red light are the most important for the germination of the plantlets and may be based on earlier and enhanced expression of auxin, cytokinin, gibberellin and jasmonate signaling genes activated by corresponding photoreceptors. The obtained results may help to improve reforestation technology; however, this problem needs further study.
PMID: 36768383
Int J Mol Sci , IF:5.923 , 2023 Jan , V24 (2) doi: 10.3390/ijms24021603
Genome-Wide Identification, Expression Analysis, and Potential Roles under Abiotic Stress of the YUCCA Gene Family in Mungbean (Vigna radiata L.).
Institute of Industrial Crops, Jiangsu Academy of Agricultural Sciences, Nanjing 210014, China.; Jiangsu Key Laboratory for Horticultural Crop Genetic Improvement, Nanjing 210014, China.; College of Life Sciences, Nanjing Agricultural University, Nanjing 210095, China.
YUCCA, belonging to the class B flavin-dependent monooxygenases, catalyzes the rate-limiting step for endogenous auxin synthesis and is implicated in plant-growth regulation and stress response. Systematic analysis of the YUCCA gene family and its stress response benefits the dissection of regulation mechanisms and breeding applications. In this study, 12 YUCCA genes were identified from the mungbean (Vigna radiata L.) genome and were named based on their similarity to AtYUCCAs. Phylogenetic analysis revealed that the 12 VrYUCCAs could be divided into 4 subfamilies. The evidence from enzymatic assays in vitro and transgenetic Arabidopsis in vivo indicated that all the isolated VrYUCCAs had biological activity in response to IAA synthesis. Expression pattern analysis showed that functional redundancy and divergence existed in the VrYUCCA gene family. Four VrYUCCAs were expressed in most tissues, and five VrYUCCAs were specifically highly expressed in the floral organs. The response toward five stresses, namely, auxin (indole-3-acetic acid, IAA), salinity, drought, high temperatures, and cold, was also investigated here. Five VrYUCCAs responded to IAA in the root, while only VrYUCCA8a was induced in the leaf. VrYUCCA2a, VrYUCCA6a, VrYUCCA8a, VrYUCCA8b, and VrYUCCA10 seemed to dominate under abiotic stresses, due to their sensitivity to the other four treatments. However, the response modes of the VrYUCCAs varied, indicating that they may regulate different stresses in distinct ways to finely adjust IAA content. The comprehensive analysis of the VrYUCCAs in this study lays a solid foundation for further investigation of VrYUCCA genes' mechanisms and applications in breeding.
PMID: 36675117
Int J Mol Sci , IF:5.923 , 2023 Jan , V24 (2) doi: 10.3390/ijms24021540
Low-Speed Clinorotation of Brachypodium distachyon and Arabidopsis thaliana Seedlings Triggers Root Tip Curvatures That Are Reminiscent of Gravitropism.
Laboratory of Genetics, University of Wisconsin-Madison, 425 Henry Mall, Madison, WI 53706, USA.; Kate Baldwin LLC, Analytical Design, Cross Plains, WI 53528, USA.
Clinostats are instruments that continuously rotate biological specimens along an axis, thereby averaging their orientation relative to gravity over time. Our previous experiments indicated that low-speed clinorotation may itself trigger directional root tip curvature. In this project, we have investigated the root curvature response to low-speed clinorotation using Arabidopsis thaliana and Brachypodium distachyon seedlings as models. We show that low-speed clinorotation triggers root tip curvature in which direction is dictated by gravitropism during the first half-turn of clinorotation. We also show that the angle of root tip curvature is modulated by the speed of clinorotation. Arabidopsis mutations affecting gravity susception (pgm) or gravity signal transduction (arg1, toc132) are shown to affect the root tip curvature response to low-speed clinorotation. Furthermore, low-speed vertical clinorotation triggers relocalization of the PIN3 auxin efflux facilitator to the lateral membrane of Arabidopsis root cap statocytes, and creates a lateral gradient of auxin across the root tip. Together, these observations support a role for gravitropism in modulating root curvature responses to clinorotation. Interestingly, distinct Brachypodium distachyon accessions display different abilities to develop root tip curvature responses to low-speed vertical clinorotation, suggesting the possibility of using genome-wide association studies to further investigate this process.
PMID: 36675054
Int J Mol Sci , IF:5.923 , 2023 Jan , V24 (2) doi: 10.3390/ijms24021182
Integrating BSA-Seq with RNA-Seq Reveals a Novel Fasciated Ear5 Mutant in Maize.
National Key Laboratory of Wheat and Maize Crop Science, College of Agronomy, Henan Agricultural University, Zhengzhou 450002, China.; The Shennong Laboratory, Zhengzhou 450002, China.
Increasing grain yield is required to meet the rapidly expanding demands for food, feed, and fuel. Inflorescence meristems are central to plant growth and development. However, the question concerning whether inflorescence development can be regulated to improve grain yield remains unclear. Here, we describe a naturally occurring single recessive mutation called fea5 that can increase grain yield in maize. Using bulk segregant analysis sequencing (BSA-seq), the candidate region was initially mapped to a large region on chromosome 4 (4.68 Mb-11.26 Mb). Transcriptome sequencing (RNA-seq) revealed a total of 1246 differentially expressed genes (DEGs), of which 835 were up-regulated and 411 were down-regulated. Further analysis revealed the enrichment of DEGs in phytohormone signal transduction. Consistently, phytohormone profiling indicated that auxin (IAA), jasmonic acid (JA), ethylene (ETH), and cytokinin (CK) levels increased significantly, whereas the gibberellin (GA) level decreased significantly in fea5. By integrating BSA-seq with RNA-seq, we identified Zm00001d048841 as the most likely candidate gene. Our results provide valuable insight into this new germplasm resource and the molecular mechanism underlying fasciated ears that produce a higher kernel row number in maize.
PMID: 36674701
Int J Mol Sci , IF:5.923 , 2023 Jan , V24 (1) doi: 10.3390/ijms24010843
Regulation of PIN-FORMED Protein Degradation.
Biotechnology Research Center, Southwest University, No. 2 Tiansheng Road, Beibei, Chongqing 400715, China.; Chongqing Key Laboratory of Plant Resource Conservation and Germplasm Innovation, Southwest University, Chongqing 400715, China.
Auxin action largely depends on the establishment of auxin concentration gradient within plant organs, where PIN-formed (PIN) auxin transporter-mediated directional auxin movement plays an important role. Accumulating studies have revealed the need of polar plasma membrane (PM) localization of PIN proteins as well as regulation of PIN polarity in response to developmental cues and environmental stimuli, amongst which a typical example is regulation of PIN phosphorylation by AGCVIII protein kinases and type A regulatory subunits of PP2A phosphatases. Recent findings, however, highlight the importance of PIN degradation in reestablishing auxin gradient. Although the underlying mechanism is poorly understood, these findings provide a novel aspect to broaden the current knowledge on regulation of polar auxin transport. In this review, we summarize the current understanding on controlling PIN degradation by endosome-mediated vacuolar targeting, autophagy, ubiquitin modification and the related E3 ubiquitin ligases, cytoskeletons, plant hormones, environmental stimuli, and other regulators, and discuss the possible mechanisms according to recent studies.
PMID: 36614276
Int J Mol Sci , IF:5.923 , 2023 Jan , V24 (1) doi: 10.3390/ijms24010756
Identification and Functional Validation of Auxin-Responsive Tabzip Genes from Wheat Leaves in Arabidopsis.
State Key Laboratory of Crop Stress Biology for Arid Areas, College of Agronomy, Northwest A&F University, Xianyang 712100, China.; State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau, Northwest A&F University, Xianyang 712100, China.
Leaves are an essential and unique organ of plants, and many studies have proved that auxin has significant impacts on the architecture of leaves, thus the manipulation of the three-dimensional structure of a leaf could provide potential strategies for crop yields. In this study, 32 basic leucine zipper transcription factors (bZIP TFs) which responded to 50 muM of indole-acetic acid (IAA) were identified in wheat leaves by transcriptome analysis. Phylogenetic analysis indicated that the 32 auxin-responsive TabZIPs were classified into eight groups with possible different functions. Phenotypic analysis demonstrated that knocking out the homologous gene of the most down-regulated auxin-responsive TabZIP6D_20 in Arabidopsis (AtHY5) decreased its sensitivity to 1 and 50 muM IAA, while the TabZIP6D_20/hy5 complementary lines recovered its sensitivity to auxin as a wild type (Wassilewskija), suggesting that the down-regulated TabZIP6D_20 was a negative factor in the auxin-signaling pathway. These results demonstrated that the auxin-responsive TabZIP genes might have various and vital functions in the architecture of a wheat leaf under auxin response.
PMID: 36614202
Int J Mol Sci , IF:5.923 , 2023 Jan , V24 (1) doi: 10.3390/ijms24010740
Genome-Wide Identification and Characterization of Auxin Response Factor (ARF) Gene Family Involved in Wood Formation and Response to Exogenous Hormone Treatment in Populus trichocarpa.
State Key Laboratory of Tree Genetics and Breeding, Northeast Forestry University, Harbin 150040, China.; Engineering Research Center of Agricultural Microbiology Technology, Ministry of Education, Heilongjiang University, Harbin 150080, China.; Heilongjiang Provincial Key Laboratory of Plant Genetic Engineering and Biological Fermentation Engineering for Cold Region, School of Life Sciences, Heilongjiang University, Harbin 150080, China.; College of Forest Resources and Environmental Science, Michigan Technological University, Houghton, MI 49931, USA.
Auxin is a key regulator that virtually controls almost every aspect of plant growth and development throughout its life cycle. As the major components of auxin signaling, auxin response factors (ARFs) play crucial roles in various processes of plant growth and development. In this study, a total of 35 PtrARF genes were identified, and their phylogenetic relationships, chromosomal locations, synteny relationships, exon/intron structures, cis-elements, conserved motifs, and protein characteristics were systemically investigated. We also analyzed the expression patterns of these PtrARF genes and revealed that 16 of them, including PtrARF1, 3, 7, 11, 13-17, 21, 23, 26, 27, 29, 31, and 33, were preferentially expressed in primary stems, while 15 of them, including PtrARF2, 4, 6, 9, 10, 12, 18-20, 22, 24, 25, 28, 32, and 35, participated in different phases of wood formation. In addition, some PtrARF genes, with at least one cis-element related to indole-3-acetic acid (IAA) or abscisic acid (ABA) response, responded differently to exogenous IAA and ABA treatment, respectively. Three PtrARF proteins, namely PtrARF18, PtrARF23, and PtrARF29, selected from three classes, were characterized, and only PtrARF18 was a transcriptional self-activator localized in the nucleus. Moreover, Y2H and bimolecular fluorescence complementation (BiFC) assay demonstrated that PtrARF23 interacted with PtrIAA10 and PtrIAA28 in the nucleus, while PtrARF29 interacted with PtrIAA28 in the nucleus. Our results provided comprehensive information regarding the PtrARF gene family, which will lay some foundation for future research about PtrARF genes in tree development and growth, especially the wood formation, in response to cellular signaling and environmental cues.
PMID: 36614182
Int J Mol Sci , IF:5.923 , 2022 Dec , V24 (1) doi: 10.3390/ijms24010624
Genome-Wide Analysis of the AAAP Gene Family in Populus and Functional Analysis of PsAAAP21 in Root Growth and Amino Acid Transport.
State Key Laboratory of Tree Genetics and Breeding, Key Laboratory of Tree Breeding and Cultivation of National Forestry and Grassland Administration, Research Institute of Forestry, Chinese Academy of Forestry, Beijing 100091, China.; Collaborative Innovation Center of Sustainable Forestry in Southern China, Nanjing Forestry University, Nanjing 210037, China.
The adventitious root (AR) is the basis for successful propagation by plant cuttings and tissue culture and is essential for maintaining the positive traits of a variety. Members of the amino acid/auxin permease (AAAP) gene family play indispensable roles in various plant metabolisms and have few studies on root growth and amino acid transport. In this study, with a systematic bioinformatics analysis of the Populus AAAP family, 83 PtrAAAPs were identified from Populus trichocarpa and grouped into 8 subfamilies. Subsequently, chromosomal distribution, genetic structure, cis-elements analysis, and expression pattern analysis of the AAAP family were performed and the potential gene AAAP21 regulating root development was screened by combining the results of RNA-Seq and QTL mapping. PsAAAP21 was proven as promoting root development by enhancing AR formation. Differentially expressed genes (DEGs) from RNA-seq results of overexpressing lines were enriched to multiple amino acid-related pathways, and the amino acid treatment to transgenic lines indicated that PsAAAP21 regulated amino acid transport, including tyrosine, methionine, and arginine. Analysis of the AAAP gene family provided a theoretical basis for uncovering the functions of AAAP genes. The identification of PsAAAP21 on root promotion and amino acid transport in Populus will help with breeding new woody plant species with strong rooting ability.
PMID: 36614067
J Fungi (Basel) , IF:5.816 , 2023 Jan , V9 (1) doi: 10.3390/jof9010090
Epichloe Endophytes Shape the Foliar Endophytic Fungal Microbiome and Alter the Auxin and Salicylic Acid Phytohormone Levels in Two Meadow Fescue Cultivars.
Department of Biology, University of Turku, 20014 Turku, Finland.; Biodiversity Unit, University of Turku, 20014 Turku, Finland.; Laboratory of Hormonal Regulations in Plants, Institute of Experimental Botany of the Czech Academy of Sciences, Rozvojova 263, 16502 Prague, Czech Republic.
Plants harbor a large diversity of endophytic microbes. Meadow fescue (Festuca pratensis) is a cool-season grass known for its symbiotic relationship with the systemic and vertically-via seeds-transmitted fungal endophyte Epichloe uncinata, yet its effects on plant hormones and the microbial community is largely unexplored. Here, we sequenced the endophytic bacterial and fungal communities in the leaves and roots, analyzing phytohormone concentrations and plant performance parameters in Epichloe-symbiotic (E+) and Epichloe-free (E-) individuals of two meadow fescue cultivars. The endophytic microbial community differed between leaf and root tissues independent of Epichloe symbiosis, while the fungal community was different in the leaves of Epichloe-symbiotic and Epichloe-free plants in both cultivars. At the same time, Epichloe symbiosis decreased salicylic acid and increased auxin concentrations in leaves. Epichloe-symbiotic plants showed higher biomass and higher seed mass at the end of the season. Our results demonstrate that Epichloe symbiosis alters the leaf fungal microbiota, which coincides with changes in phytohormone concentrations, indicating that Epichloe endophytes affect both plant immune responses and other fungal endophytes. Whether the effect of Epichloe endophytes on other fungal endophytes is connected to changes in phytohormone concentrations remains to be elucidated.
PMID: 36675911
Front Plant Sci , IF:5.753 , 2023 , V14 : P1105521 doi: 10.3389/fpls.2023.1105521
Jasmonic acid negatively regulates branch growth in pear.
Qingdao Key Laboratory of Genetic Improvement and Breeding in Horticultural Plants, Engineering Laboratory of Genetic Improvement of Horticultural Crops of Shandong Province, College of Horticulture, Qingdao Agricultural University, Qingdao, China.; Haidu College, Qingdao Agricultural University, Laiyang, China.
The quality of seedlings is an important factor for development of the pear industry. A strong seedling with few branches and suitable internodes is ideal material as a rootstock for grafting and breeding. Several branching mutants of pear rootstocks were identified previously. In the present study, 'QAU-D03' (Pyrus communis L.) and it's mutants were used to explore the mechanism that affects branch formation by conducting phenotypic trait assessment, hormone content analysis, and transcriptome analysis. The mutant plant (MP) showed fewer branches, shorter 1-year-old shoots, and longer petiole length, compared to original plants (OP), i.e., wild type. Endogenous hormone analysis revealed that auxin, cytokinin, and jasmonic acid contents in the stem tips of MP were significantly higher than those of the original plants. In particular, the jasmonic acid content of the MP was 1.8 times higher than that of the original plants. Transcriptome analysis revealed that PcCOI1, which is a transcriptional regulatory gene downstream of the jasmonic acid signaling pathway, was expressed more highly in the MP than in the original plants, whereas the expression levels of PcJAZ and PcMYC were reduced in the MP compared with that of the original plants. In response to treatment with exogenous methyl jasmonate, the original plants phenotype was consistent with that of the MP in developing less branches. These results indicate that jasmonic acid negatively regulates branch growth of pear trees and that jasmonic acid downstream regulatory genes play a crucial role in regulating branching.
PMID: 36824194
Front Plant Sci , IF:5.753 , 2023 , V14 : P1096802 doi: 10.3389/fpls.2023.1096802
Evaluation of convolutional neural networks for herbicide susceptibility-based weed detection in turf.
College of Mechanical and Electronic Engineering, Nanjing Forestry University, Nanjing, Jiangsu, China.; Peking University Institute of Advanced Agricultural Sciences / Shandong Laboratory of Advanced Agricultural Sciences at Weifang, Weifang, Shandong, China.; Department of Crop and Soil Sciences, University of Georgia, Griffin, GA, United States.
Deep learning methods for weed detection typically focus on distinguishing weed species, but a variety of weed species with comparable plant morphological characteristics may be found in turfgrass. Thus, it is difficult for deep learning models to detect and distinguish every weed species with high accuracy. Training convolutional neural networks for detecting weeds susceptible to herbicides can offer a new strategy for implementing site-specific weed detection in turf. DenseNet, EfficientNet-v2, and ResNet showed high F(1) scores (>/=0.986) and MCC values (>/=0.984) to detect and distinguish the sub-images containing dollarweed, goosegrass, old world diamond-flower, purple nutsedge, or Virginia buttonweed growing in bermudagrass turf. However, they failed to reliably detect crabgrass and tropical signalgrass due to the similarity in plant morphology. When training the convolutional neural networks for detecting and distinguishing the sub-images containing weeds susceptible to ACCase-inhibitors, weeds susceptible to ALS-inhibitors, or weeds susceptible to synthetic auxin herbicides, all neural networks evaluated in this study achieved excellent F(1) scores (>/=0.995) and MCC values (>/=0.994) in the validation and testing datasets. ResNet demonstrated the fastest inference rate and outperformed the other convolutional neural networks on detection efficiency, while the slow inference of EfficientNet-v2 may limit its potential applications. Grouping different weed species growing in turf according to their susceptibility to herbicides and detecting and distinguishing weeds by herbicide categories enables the implementation of herbicide susceptibility-based precision herbicide application. We conclude that the proposed method is an effective strategy for site-specific weed detection in turf, which can be employed in a smart sprayer to achieve precision herbicide spraying.
PMID: 36818827
Front Plant Sci , IF:5.753 , 2023 , V14 : P1107550 doi: 10.3389/fpls.2023.1107550
Overdominant expression of genes plays a key role in root growth of tobacco hybrids.
College of Tobacco, Guizhou University, Guiyang, China.; Key Laboratory of Tobacco Quality in Guizhou Province, Guiyang, China.; College of Agriculture, Guizhou University, Guiyang, China.
Heterosis has greatly improved the yield and quality of crops. However, previous studies often focused on improving the yield and quality of the shoot system, while research on the root system was neglected. We determined the root numbers of 12 F(1) hybrids, all of which showed strong heterosis, indicating that tobacco F(1) hybrids have general heterosis. To understand its molecular mechanism, we selected two hybrids with strong heterosis, GJ (G70 x Jiucaiping No.2) and KJ (K326 x Jiucaiping No.2), and their parents for transcriptome analysis. There were 84.22% and 90.25% of the differentially expressed genes were overdominantly expressed. The enrichment analysis of these overdominantly expressed genes showed that "Plant hormone signal transduction", "Phenylpropanoid biosynthesis", "MAPK signaling pathway - plant", and "Starch and sucrose metabolism" pathways were associated with root development. We focused on the analysis of the biosynthetic pathways of auxin(AUX), cytokinins(CTK), abscisic acid(ABA), ethylene(ET), and salicylic acid(SA), suggesting that overdominant expression of these hormone signaling pathway genes may enhance root development in hybrids. In addition, Nitab4.5_0011528g0020ã€<81>Nitab4.5_0003282g0020ã€<81>Nitab4.5_0004384g0070 may be the genes involved in root growth. Genome-wide comparative transcriptome analysis enhanced our understanding of the regulatory network of tobacco root development and provided new ideas for studying the molecular mechanisms of tobacco root development.
PMID: 36798711
Front Plant Sci , IF:5.753 , 2023 , V14 : P1117156 doi: 10.3389/fpls.2023.1117156
Abscisic acid mediated strawberry receptacle ripening involves the interplay of multiple phytohormone signaling networks.
College of Agriculture and Biotechnology, Zhejiang University, Zijingang Campus, Hangzhou, China.; Zhejiang Provincial Key Laboratory of Horticultural Plant Integrative Biology, Zhejiang University, Zijingang Campus, Hangzhou, China.; State Agriculture Ministry Laboratory of Horticultural Plant Growth, Development and Quality Improvement, Zhejiang University, Hangzhou, China.; Institute of Horticulture, Zhejiang Academy of Agricultural Sciences, Hangzhou, China.; Plant Biology Section, School of Integrative Plant Science, Cornell University, Ithaca, NY, United States.; United States Department of Agriculture - Agricultural Research Service and Boyce Thompson Institute for Plant Research, Cornell University, Ithaca, NY, United States.
As a canonical non-climacteric fruit, strawberry (Fragaria spp.) ripening is mainly mediated by abscisic acid (ABA), which involves multiple other phytohormone signalings. Many details of these complex associations are not well understood. We present an coexpression network, involving ABA and other phytohormone signalings, based on weighted gene coexpression network analysis of spatiotemporally resolved transcriptome data and phenotypic changes of strawberry receptacles during development and following various treatments. This coexpression network consists of 18,998 transcripts and includes transcripts related to phytohormone signaling pathways, MADS and NAC family transcription factors and biosynthetic pathways associated with fruit quality. Members of eight phytohormone signaling pathways are predicted to participate in ripening and fruit quality attributes mediated by ABA, of which 43 transcripts were screened to consist of the hub phytohormone signalings. In addition to using several genes reported from previous studies to verify the reliability and accuracy of this network, we explored the role of two hub signalings, small auxin up-regulated RNA 1 and 2 in receptacle ripening mediated by ABA, which are also predicted to contribute to fruit quality. These results and publicly accessible datasets provide a valuable resource to elucidate ripening and quality formation mediated by ABA and involves multiple other phytohormone signalings in strawberry receptacle and serve as a model for other non-climacteric fruits.
PMID: 36794230
Front Plant Sci , IF:5.753 , 2023 , V14 : P1136616 doi: 10.3389/fpls.2023.1136616
Integrated transgene and transcriptome reveal the molecular basis of MdWRKY87 positively regulate adventitious rooting in apple rootstock.
College of Horticulture, Qingdao Agricultural University, Qingdao, China.; Engineering Laboratory of Genetic Improvement of Horticultural Crops of Shandong Province, Qingdao Agricultural University, Qingdao, China.; Laboratory of Quality & Safety Risk Assessment for Fruit (Qingdao), Ministry of Agriculture and Rural Affairs, Qingdao Agricultural University, Qingdao, China.; Shandong Academy of Grape, Shandong Academy of Agricultural Sciences, Jinan, China.; Weihai Yingjuval Nursery Limited Company, Weihai International Port Economic and Technological Develepment District, Weihai, Shandong, China.; College of Horticulture and Plant Protection, Inner Mongolia Agricultural University, Hohhot, China.
For most fruit and forest species vegetative propagated from elite genotypes, adventitious rooting is essential. The ability to form adventitious roots significantly decreased during the juvenile to adult phase change. Apart from the miR156-SPL pathway, whether there is another regulation mechanism controlling age-dependent adventitious rooting ability remained largely unknown. In the present study, we showed that MdWRKY87 expression level was positively correlation with adventitious rooting ability. In addition, over-expressing of MdWRKY87 in tobacco leads to enhanced adventitious rooting ability, more adventitious root number and accelerated adventitious rooting process. Comparative transcriptome profiling indicated that MdWRKY87 overexpression can activate the expression of adventitious rooting-induced genes, such as WOX11 and AIL. In addition, MdWRKY87 overexpression can inhibit the transcription of adventitious rooting-repressed genes, such as AUX/IAAs and type-B cytokinin RRs. Collectively, here we demonstrated that higher expression level of MdWRKY87 contributes to age-dependent adventitious rooting-competent in juvenile apple rootstock.
PMID: 36778677
Front Plant Sci , IF:5.753 , 2023 , V14 : P1065208 doi: 10.3389/fpls.2023.1065208
Exogenous spermidine improved drought tolerance in Ilex verticillata seedlings.
State Key Laboratory of Subtropical Silviculture, Zhejiang Agricultural and Forestry University, Hangzhou, China.; Zhejiang Provincial Key Laboratory of Forest Aromatic Plants-based Healthcare Functions, Zhejiang Agricultural and Forestry University, Hangzhou, China.
Winterberry (Ilex verticillata (L.) A. Gray) is a recently introduced ornamental tree species in China that has not been closely investigated for its drought resistance. In this study, we used two-year-old cuttings from I. verticillata (L.) A. Gray and two representative varieties derived from it, I. verticillata 'Oosterwijk' and I. verticillata 'Jim Dandy', as materials to investigate how this plant responds to drought stress and whether exogenous spermidine (SPD) can alleviate the negative effects caused by drought stress. The results showed that as the degree of drought stress increased, the leaves of winterberry seedlings became chlorotic, and their edges became dry. Similarly, the relative water content, specific leaf weight, chlorophyll content, leaf nitrogen content, net photosynthetic rate, stomatal conductance and transpiration rate were significantly reduced, whereas the content of malondialdehyde continuously increased with the degree of drought stress. The activities of superoxide dismutase, peroxidase, and catalase increased under moderate drought stress and then decreased under severe drought stress. The levels of soluble sugar and abscisic acid continued to increase, while those of auxin and gibberellic acid decreased. When compared with individual drought stress, an increase in the amount of external SPD clearly alleviated the effect of drought stress on winterberry seedlings. The combined phenotypes and physiological indices of the winterberry leaves under drought stress conditions revealed that the drought resistance of the native species was significantly higher than its two varieties. This finding serves as an important theoretical foundation for the popularization and application of I. verticillata (L.) A. Gray and the two varieties.
PMID: 36743484
Front Plant Sci , IF:5.753 , 2022 , V13 : P1058092 doi: 10.3389/fpls.2022.1058092
Arbuscular mycorrhizal fungus alleviates anthracnose disease in tea seedlings.
Tea Research Institute, Anhui Academy of Agricultural Sciences, Huangshan, China.
Tea has been gaining increasing popularity all over the world in recent years, and its yield and quality depend on the growth and development of tea plants [Camellia sinensis (L.) Kuntze] in various environments. Nowadays, biotic stress and extreme weather, such as high temperature, drought, waterlogging, pests, and diseases, bring about much pressure on the production of tea with high quality. Wherein anthracnose, which is the most common and serious disease of tea plants, has earned more and more attention, as its control mainly relies on chemical pesticides. Arbuscular mycorrhizal fungi (AMF), forming symbiosis with most terrestrial plants, participate in plant resistance against the anthracnose disease, which was found by previous studies in a few herbaceous plants. However, there are a few studies about arbuscular mycorrhizal (AM) fungal regulation of the resistance to the anthracnose pathogen in woody plants so far. In this paper, we investigated the effect of AMF on the development of anthracnose caused by Colletotrichum camelliae and tried to decipher the pertinent mechanism through transcriptome analysis. Results showed that inoculating AMF significantly reduced the damage of anthracnose on tea seedlings by reducing the lesion area by 35.29% compared to that of the control. The content of superoxide anion and activities of catalase and peroxidase significantly increased (P < 0.05) in mycorrhizal treatment in response to the pathogen with 1.23, 2.00, and 1.39 times higher, respectively, than those in the control. Pathways of plant hormone signal transduction, mitogen-activated protein kinase (MAPK) signaling, and phenylpropanoid biosynthesis might play roles in this regulation according to the transcriptomic results. Further redundancy analysis (RDA) and partial least squares structural equation modeling (PLS-SEM) analysis found that plant hormones, such as auxin and ethylene, and the antioxidant system (especially peroxidase) were of great importance in the AM fungal alleviation of anthracnose. Our results preliminarily indicated the mechanisms of enhanced resistance in mycorrhizal tea seedlings to the anthracnose pathogen and provided a theoretical foundation for the application of AMF as one of the biological control methods in tea plantations.
PMID: 36726674
Front Plant Sci , IF:5.753 , 2022 , V13 : P1060021 doi: 10.3389/fpls.2022.1060021
Endocytic trafficking induces lateral root founder cell specification in Arabidopsis thaliana in a process distinct from the auxin-induced pathway.
Plant Molecular Biology Centre, Department of Biology, Facultad de Ciencias, Universidad de Chile, Santiago, Chile.
Plants can modify their body structure, such as their root architecture, post-embryonically. For example, Arabidopsis thaliana can develop lateral roots as part of an endogenous program or in response to biotic and abiotic stimuli. Root pericycle cells are specified to become lateral root founder cells, initiating lateral root organogenesis. We used the endocytic trafficking inducer Sortin2 to examine the role of endomembrane trafficking in lateral root founder cell specification. Our results indicate that Sortin2 stimulation turns on a de novo program of lateral root primordium formation that is distinct from the endogenous program driven by auxin. In this distinctive mechanism, extracellular calcium uptake and endocytic trafficking toward the vacuole are required for lateral root founder cell specification upstream of the auxin module led by AUX/IAA28. The auxin-dependent TIR1/AFB F-boxes and auxin polar transport are dispensable for the endocytic trafficking-dependent lateral root founder cell specification; however, a different set of F-box proteins and a functional SCF complex are required. The endocytic trafficking could constitute a convenient strategy for organogenesis in response to environmental conditions.
PMID: 36726665
Front Plant Sci , IF:5.753 , 2022 , V13 : P1054821 doi: 10.3389/fpls.2022.1054821
Morphophysiological and transcriptome analysis reveal that reprogramming of metabolism, phytohormones and root development pathways governs the potassium (K(+)) deficiency response in two contrasting chickpea cultivars.
National Institute of Plant Genome Research, New Delhi, India.
Potassium (K(+)) is an essential macronutrient for plant growth and development. K(+) deficiency hampers important plant processes, such as enzyme activation, protein synthesis, photosynthesis and stomata movement. Molecular mechanism of K(+) deficiency tolerance has been partly understood in model plants Arabidopsis, but its knowledge in legume crop chickpea is missing. Here, morphophysiological analysis revealed that among five high yielding desi chickpea cultivars, PUSA362 shows stunted plant growth, reduced primary root growth and low K(+) content under K(+) deficiency. In contrast, PUSA372 had negligible effect on these parameters suggesting that PUSA362 is K(+) deficiency sensitive and PUSA372 is a K(+) deficiency tolerant chickpea cultivar. RNA-seq based transcriptome analysis under K(+) deficiency revealed a total of 820 differential expressed genes (DEG's) in PUSA362 and 682 DEGs in PUSA372. These DEGs belongs to different functional categories, such as plant metabolism, signal transduction components, transcription factors, ion/nutrient transporters, phytohormone biosynthesis and signalling, and root growth and development. RNA-seq expression of randomly selected 16 DEGs was validated by RT-qPCR. Out of 16 genes, 13 showed expression pattern similar to RNA-seq expression, that verified the RNA-seq expression data. Total 258 and 159 genes were exclusively up-regulated, and 386 and 347 genes were down-regulated, respectively in PUSA362 and PUSA372. 14 DEGs showed contrasting expression pattern as they were up-regulated in PUSA362 and down-regulated in PUSA372. These include somatic embryogenesis receptor-like kinase 1, thaumatin-like protein, ferric reduction oxidase 2 and transcription factor bHLH93. Nine genes which were down-regulated in PUSA362 found to be up-regulated in PUSA372, including glutathione S-transferase like, putative calmodulin-like 19, high affinity nitrate transporter 2.4 and ERF17-like protein. Some important carbohydrate metabolism related genes, like fructose-1,6-bisphosphatase and sucrose synthase, and root growth related Expansin gene were exclusively down-regulated, while an ethylene biosynthesis gene 1-aminocyclopropane-1-carboxylate oxidase 1 (ACO1) was up-regulated in PUSA362. Interplay of these and several other genes related to hormones (auxin, cytokinin, GA etc.), signal transduction components (like CBLs and CIPKs), ion transporters and transcription factors might underlie the contrasting response of two chickpea cultivars to K(+) deficiency. In future, some of these key genes will be utilized in genetic engineering and breeding programs for developing chickpea cultivars with improved K(+) use efficiency (KUE) and K(+) deficiency tolerance traits.
PMID: 36714783
Front Plant Sci , IF:5.753 , 2022 , V13 : P1096645 doi: 10.3389/fpls.2022.1096645
Salicylic acid delays pear fruit senescence by playing an antagonistic role toward ethylene, auxin, and glucose in regulating the expression of PpEIN3a.
College of Horticulture, Hebei Agricultural University, Baoding, Hebei, China.
Salicylic acid (SA) and ethylene (ET) are crucial fruit senescence hormones. SA inhibited ET biosynthesis. However, the mechanism of SA delaying fruit senescence is less known. ETHYLENE INSENSITIVE 3 (EIN3), a key positive switch in ET perception, functions as a transcriptional activator and binds to the primary ET response element that is present in the promoter of the ETHYLENE RESPONSE FACTOR1 gene. In this study, a gene encoding putative EIN3 protein was cloned from sand pear and designated as PpEIN3a. The deduced PpEIN3a contains a conserved EIN3 domain. The evolutionary analysis results indicated that PpEIN3a belonged to the EIN3 superfamily. Real-time quantitative PCR analysis revealed that the accumulation of PpEIN3a transcripts were detected in all tissues of this pear. Moreover, PpEIN3a expression was regulated during fruit development. Interestingly, the expression of PpEIN3a was downregulated by SA but upregulated by ET, auxin, and glucose. Additionally, the contents of free and conjugated SA were higher than those of the control after SA treatment. While the content of ET and auxin (indole-3-acetic acid, IAA) dramatically decreased after SA treatment compared with control during fruit senescence. The content of glucose increased when fruit were treated by SA for 12 h and then there were no differences between SA treatment and control fruit during the shelf life. SA also delayed the decrease in sand pear (Pyrus pyrifolia Nakai. 'Whangkeumbae') fruit firmness. The soluble solid content remained relatively stable between the SA treated and control fruits. This study showed that SA plays an antagonistic role toward ET, auxin, and glucose in regulating the expression of PpEIN3a to delay fruit senescence.
PMID: 36714736
Front Plant Sci , IF:5.753 , 2022 , V13 : P1088278 doi: 10.3389/fpls.2022.1088278
The Arabidopsis thaliana trehalose-6-phosphate phosphatase gene AtTPPI regulates primary root growth and lateral root elongation.
School of Life Sciences, Jiangsu Normal University, Xuzhou, Jiangsu, China.; Institute of Genetic and Developmental Biology, Chinese Academy of Sciences, Beijing, China.; Lushan Botanical Garden, Chinese Academy of Sciences, Jiujiang, Jiangxi, China.; Technical Services and Sales Department, Zhengzhou Xuanyuan Biotechnology Co. LTD, Zhengzhou, Henan, China.
Roots are the main organs through which plants absorb water and nutrients. As the key phytohormone involved in root growth, auxin functions in plant environmental responses by modulating auxin synthesis, distribution and polar transport. The Arabidopsis thaliana trehalose-6-phosphate phosphatase gene AtTPPI can improve root architecture, and tppi1 mutants have significantly shortened primary roots. However, the mechanism underlying the short roots of the tppi1 mutant and the upstream signaling pathway and downstream genes regulated by AtTPPI are unclear. Here, we demonstrated that the AtTPPI gene could promote auxin accumulation in AtTPPI-overexpressing plants. By comparing the transcriptomic data of tppi1 and wild-type roots, we found several upregulations of auxin-related genes, including GH3.3, GH3.9 and GH3.12, may play an important role in the AtTPPI gene-mediated auxin transport signaling pathway, ultimately leading to changes in auxin content and primary root length. Moreover, increased AtTPPI expression can regulate primary root growth and lateral root elongation under different concentration of nitrate conditions. Overall, constitutive expression of AtTPPI increased auxin contents and improved lateral root elongation, constituting a new method for improving the nitrogen utilization efficiency of plants.
PMID: 36714693
Front Plant Sci , IF:5.753 , 2022 , V13 : P1097998 doi: 10.3389/fpls.2022.1097998
Characterization of cadmium accumulation mechanism between eggplant (Solanum melongena L.) cultivars.
Research Center for Environmental Pollution Control Technology, School of Chemical and Environmental Engineering, Hunan Institute of Technology, Hengyang, China.
Excessive cadmium (Cd) accumulation in vegetables due to farmland pollution constitutes a serious threat to human health. Eggplant has a tendency to accumulate Cd. To investigate the mechanism of the differences in Cd accumulation levels between high-Cd (BXGZ) and low-Cd (MYQZ) eggplant cultivar, physiological and biochemical indicators and mRNA expression of eggplant were examined using photosynthetic apparatus, biochemical test kits, Fourier transform infrared (FTIR) spectroscopy and transcriptome sequencing, etc. The results of biochemical test kits and FTIR revealed that MYQZ enhanced pectin methylesterase (PME) activity, and lignin and pectin content in the root cell wall, which was associated with the upregulation of PME, cinnamyl-alcohol dehydrogenase and peroxidase (PODs). Higher levels of cysteine and glutathione (GSH) contents and upregulation of genes associated with sulfur metabolism, as well as higher expression of ATP-binding cassette transporters (ABCs), cation exchangers (CAX) and metal tolerance proteins (MTPs) were observed in MYQZ. In BXGZ, the higher stomatal density and stomatal aperture as well as higher levels of Ca(2+) binding protein-1 (PCaP1) and aquaporins and lower levels of A2-type cyclins (CYCA2-1) are consistent with an enhanced transpiration rate in BXGZ. Furthermore, a more developed root system was shown to be associated with higher levels of auxin response factor (ARF19), GATA transcription factors (GATA4, 5 and 11) and auxin efflux carrier component (PIN5) in BXGZ. In conclusion, highly active PME, and higher levels of lignin and pectin in MYQZ are expected to reduce Cd toxicity, while Cd translocation can be inhibited with the help of ABC and other Cd transporters. As for BXGZ, the uptake and translocation of Cd were enhanced by the developed root system and stronger transpiration.
PMID: 36699861
Front Plant Sci , IF:5.753 , 2022 , V13 : P1043757 doi: 10.3389/fpls.2022.1043757
Combined metabolomic and transcriptomic analysis reveals key components of OsCIPK17 overexpression improves drought tolerance in rice.
School of Life Sciences, Nantong University, Nantong, China.
Oryza Sativa is one of the most important food crops in China, which is easily affected by drought during its growth and development. As a member of the calcium signaling pathway, CBL-interacting protein kinase (CIPK) plays an important role in plant growth and development as well as environmental stress. However, there is no report on the function and mechanism of OsCIPK17 in rice drought resistance. We combined transcriptional and metabonomic analysis to clarify the specific mechanism of OsCIPK17 in response to rice drought tolerance. The results showed that OsCIPK17 improved drought resistance of rice by regulating deep roots under drought stress; Response to drought by regulating the energy metabolism pathway and controlling the accumulation of citric acid in the tricarboxylic acid (TCA) cycle; Our exogenous experiments also proved that OsCIPK17 responds to citric acid, and this process involves the auxin metabolism pathway; Exogenous citric acid can improve the drought resistance of overexpression plants. Our research reveals that OsCIPK17 positively regulates rice drought resistance and participates in the accumulation of citric acid in the TCA cycle, providing new insights for rice drought resistance.
PMID: 36699859
Front Plant Sci , IF:5.753 , 2022 , V13 : P1058421 doi: 10.3389/fpls.2022.1058421
Microspore embryogenesis induction by mannitol and TSA results in a complex regulation of epigenetic dynamics and gene expression in bread wheat.
Departamento de Genetica y Produccion Vegetal, Estacion Experimental de Aula Dei, Consejo Superior de Investigaciones Cientificas (EEAD-CSIC), Zaragoza, Spain.; Departamento de Patologia, Anatomia y Fisiologia, Facultad de Ciencias, Universidad de Navarra, Pamplona, Spain.
Reprogramming of microspores development towards embryogenesis mediated by stress treatment constitutes the basis of doubled haploid production. Recently, compounds that alter histone post-translational modifications (PTMs) have been reported to enhance microspore embryogenesis (ME), by altering histones acetylation or methylation. However, epigenetic mechanisms underlying ME induction efficiency are poorly understood. In this study, the epigenetic dynamics and the expression of genes associated with histone PTMs and ME induction were studied in two bread wheat cultivars with different ME response. Microspores isolated at 0, 3 and 5 days, treated with 0.7M mannitol (MAN) and 0.7M mannitol plus 0.4microM trichostatin A (TSA), which induced ME more efficiently, were analyzed. An additional control of gametophytic development was included. Microspores epigenetic state at the onset of ME induction was distinctive between cultivars by the ratio of H3 variants and their acetylated forms, the localization and percentage of labeled microspores with H3K9ac, H4K5ac, H4K16ac, H3K9me2 and H3K27me3, and the expression of genes related to pollen development. These results indicated that microspores of the high responding cultivar could be at a less advanced stage in pollen development. MAN and TSA resulted in a hyperacetylation of H3.2, with a greater effect of TSA. Histone PTMs were differentially affected by both treatments, with acetylation being most concerned. The effect of TSA was observed in the H4K5ac localization pattern at 3dT in the mid-low responding cultivar. Three gene networks linked to ME response were identified. TaHDT1, TaHAG2, TaYAO, TaNFD6-A, TabZIPF1 and TaAGO802-B, associated with pollen development, were down-regulated. TaHDA15, TaHAG3, TaHAM, TaYUC11D, Ta-2B-LBD16 TaMS1 and TaDRM3 constituted a network implicated in morphological changes by auxin signaling and cell wall modification up-regulated at 3dT. The last network included TaHDA18, TaHAC1, TaHAC4, TaABI5, TaATG18fD, TaSDG1a-7A and was related to ABA and ethylene hormone signaling pathways, DNA methylation and autophagy processes, reaching the highest expression at 5dT. The results indicated that TSA mainly modified the regulation of genes related to pollen and auxin signaling. This study represents a breakthrough in identifying the epigenetic dynamics and the molecular mechanisms governing ME induction efficiency, with relevance to recalcitrant wheat genotypes and other crops.
PMID: 36699843
Front Plant Sci , IF:5.753 , 2022 , V13 : P1035157 doi: 10.3389/fpls.2022.1035157
Genome sequencing and resequencing identified three horizontal gene transfers and uncovered the genetic mechanism on the intraspecies adaptive evolution of Gastrodia elata Blume.
School of Health and Life Science, Kaili University, Kaili, Guizhou, China.; State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, South China Agricultural University, Guangzhou, China.; Guangdong Provincial Key Laboratory of Plant Molecular Breeding, South China Agricultural University, Guangzhou, China.; College of Agriculture, South China Agricultural University, Guangzhou, Guangdong, China.
Horizontal gene transfer is a rare and useful genetic mechanism in higher plants. Gastrodia elata Blume (GE) (Orchidaceae), well known as traditional medicinal material in East Asia, adopts a heterotrophic lifestyle, thus being considered to be more prone to horizontal gene transfer (HGT). GE is a "polytypic species" that currently comprised of five recognized forms according to the plant morphology. G. elata Blume forma elata (GEE) and G. elata Bl.f.glauca (GEG) are two common forms that naturally grow in different habitats with difference in altitude and latitude. G. elata Bl.f.viridis (GEV) often occurs sporadically in cultivated populations of GEE and GEG. However, the genetic relationships and genetic mechanism underpinned the divergent ecological adaptations of GEE and GEG have not been revealed. Here, we assembled a chromosome-level draft genome of GEE with 1.04 Gb. Among predicted 17,895 protein coding genes, we identified three HGTs. Meanwhile, we resequenced 10 GEE accessions, nine GEG accessions, and 10 GEV accessions, and identified two independent genetic lineages: GEG_pedigree (GEG individuals and GEV individuals collected from GEG populations) and GEE_pedigree (GEE individuals and GEV individuals collected from GEE populations), which strongly support the taxonomic status of GEE and GEG as subspecies, not as different forms. In highly differentiated genomic regions of GEE_pedigree and GEG_pedigree, three chalcone synthase-encoding genes and one Phox/Bem1p (PB1) domain of encoding Auxin (AUX)/Indoleacetic acid (IAA) were identified in selection sweeping genome regions, which suggested that differentiation between GEE_pedigree and GEG_pedigree was promoted by the selection of genes related to photoresponse and growth and development. Overall, this new genome would be helpful for breeding and utilization of GE and the new findings would deepen the understanding about ecological adaptation and evolution of GE.
PMID: 36684780
Front Plant Sci , IF:5.753 , 2022 , V13 : P1019152 doi: 10.3389/fpls.2022.1019152
Effects of exogenous auxin on yield in foxtail millet (Setaria italica L.) when applied at the grain-filling stage.
Shanxi Agricultural University, Taiyuan, Shanxi, China.
Foxtail millet (Setaria italica L.) is of high nutritious value, which is an important crop in arid and semi-arid regions. The objective of this experiment was to explore the effects of the synthetic auxin naphthalene acetic acid (NAA) on the physiological processes of foxtail millet, and to provide a theoretical basis and technical approaches for its efficient use in millet cultivation. Two foxtail millet varieties ('Jingu 21' and 'Zhangzagu 5') were treated with six concentrations of NAA from 0-144 mg L(-1) at the grain-filling stage in field experiments. The photosynthetic pigment contents, gas exchange parameters, chlorophyll fluorescence parameters, and grain yield were measured in foxtail millet. The results showed that low concentrations of NAA (18-36 mg L(-1)) increased the contents of photosynthetic pigments, and increased the activities of antioxidant enzymes, the photosynthetic rate, and the activity of photosystem system II (PS II). At higher NAA concentrations, the facilitation effect of the treatments diminished, showing a clear concentration effect. In this study, yield was significantly and positively correlated with PS II effective quantum yield (Y(II)) and the PSII electron transport rate (ETR), and the net photosynthetic rate (Pn) was significantly and positively correlated with chlorophyll content, stomatal conductance (Gs), Y(II), and ETR. These results also indicated that exogenous NAA application promotes the production of ATP and NADPH by increasing the efficiency of electron transfer within the photosystems and also improved photochemical utilization, which facilitates the fixation and reduction of carbon, ultimately leading to an increase in Pn and increasing grain yield in foxtail millet.
PMID: 36684766
Front Plant Sci , IF:5.753 , 2022 , V13 : P1060965 doi: 10.3389/fpls.2022.1060965
Genome-wide identification and expression analysis of AUX/LAX family genes in Chinese hickory (Carya cathayensis Sarg.) Under various abiotic stresses and grafting.
State Key Laboratory of Subtropical Silviculture, Zhejiang Agriculture and Forestry (A&F) University, Hangzhou, China.; Zhejiang Provincial Key Laboratory of Forest Aromatic Plants-based Healthcare Functions, Zhejiang Agriculture and Forestry (A&F) University, Hangzhou, China.; College of Life Sciences, Nanjing Agricultural University, Nanjing, Jiangsu, China.; Departments of Public Health Sciences and Statistics, Center for Statistical Genetics, Pennsylvania State University, Hershey, PA, United States.
Auxin is essential for regulating plant growth and development as well as the response of plants to abiotic stresses. AUX/LAX proteins are auxin influx transporters belonging to the amino acid permease family of proton-driven transporters, and are involved in the transport of indole-3-acetic acid (IAA). However, how AUX/LAX genes respond to abiotic stresses in Chinese hickory is less studied. For the first time identification, structural characteristics as well as gene expression analysis of the AUX/LAX gene family in Chinese hickory were conducted by using techniques of gene cloning and real-time fluorescent quantitative PCR. Eight CcAUX/LAXs were identified in Chinese hickory, all of which had the conserved structural characteristics of AUX/LAXs. CcAUX/LAXs were most closely related to their homologous proteins in Populus trichocarpa , which was in consistence with their common taxonomic character of woody trees. CcAUX/LAXs exhibited different expression profiles in different tissues, indicating their varying roles during growth and development. A number of light-, hormone-, and abiotic stress responsive cis-acting regulatory elements were detected on the promoters of CcAUX/LAX genes. CcAUX/LAX genes responded differently to drought and salt stress treatments to varying degrees. Furthermore, CcAUX/LAX genes exhibited complex expression changes during Chinese hickory grafting. These findings not only provide a valuable resource for further functional validation of CcAUX/LAXs, but also contribute to a better understanding of their potential regulatory functions during grafting and abiotic stress treatments in Chinese hickory.
PMID: 36684757
Front Plant Sci , IF:5.753 , 2022 , V13 : P1023088 doi: 10.3389/fpls.2022.1023088
Root pruning improves maize water-use efficiency by root water absorption.
State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau, Northwest Agriculture and Forestry University, Yangling, Shaanxi, China.; College of Forestry, Northwest Agriculture and Forestry University, Yangling, Shaanxi, China.; School of Pharmacy, Weifang Medical University, Weifang, China.; Geography and Environmental Engineering Department, Baoji University of Arts and Sciences, Baoji, China.; The University of Western Australia Institute of Agriculture, and University of Western Australia School of Agriculture and Environment, The University of Western Australia, Perth, WA, Australia.; Key Laboratory of Agricultural Soil and Water Engineering in Arid and Semiarid Areas, Ministry of Education, Northwest Agriculture and Forestry University, Yangling, China.
Root systems are an important component of plants that impact crop water-use efficiency (WUE) and yield. This study examined the effects of root pruning on maize yield, WUE, and water uptake under pot and hydroponic conditions. The pot experiment showed that root pruning significantly decreased root/shoot ratio. Both small root pruning (cut off about 1/5 of the root system, RP1) and large root pruning (cut off about 1/3 of the root system, RP2) improved WUE and root hydraulic conductivity (Lpr) in the residual root system. Compared with that in the un-cut control, at the jointing stage, RP1 and RP2 increased Lpr by 43.9% and 31.5% under well-watered conditions and 27.4% and 19.8% under drought stress, respectively. RP1 increased grain yield by 12.9% compared with that in the control under well-watered conditions, whereas both pruning treatments did not exhibit a significant effect on yield under drought stress. The hydroponic experiment demonstrated that root pruning did not reduce leaf water potential but increased residual root hydraulic conductivity by 26.2% at 48 h after root pruning under well-watered conditions. The foregoing responses may be explained by the upregulation of plasma membrane intrinsic protein gene and increases in abscisic acid and jasmonic acid in roots. Increased auxin and salicylic acid contributed to the compensated lateral root growth. In conclusion, root pruning improved WUE in maize by root water uptake.
PMID: 36684736
Front Plant Sci , IF:5.753 , 2022 , V13 : P994268 doi: 10.3389/fpls.2022.994268
Integrated analysis of transcriptome and microRNAs associated with exogenous calcium-mediated enhancement of hypoxic tolerance in cucumber seedlings (Cucumis sativus L.).
Shanghai Key Lab of Protected Horticultural Technology, Horticultural Research Institute, Shanghai Academy of Agricultural Sciences, Shanghai, China.; Shanghai Dushi Green Engineering Co., Ltd., Shanghai, China.
Plants often suffer from hypoxic stress due to flooding caused by extreme weather. Hypoxia usually leads to restricted oxygen supply and alters metabolic patterns from aerobic to anaerobic. Cucumber roots are fragile and highly sensitive to damage from hypoxic stress. The purpose of this study was to investigate the regulatory mechanism of exogenous calcium alleviating hypoxic stress in cucumber through transcriptome and small RNAs analysis. Three treatments were performed in this paper, including untreated-control (CK), hypoxic stress (H), and hypoxic stress + exogenous calcium treatment (H + Ca(2+)). A large number of differentially expressed genes (DEGs) were identified, 1,463 DEGs between CK vs H, 3,399 DEGs between H vs H + Ca(2+), and 5,072 DEGs between CK vs H + Ca(2+), respectively. KEGG analysis of DEGs showed that exogenous calcium could activate hormone signaling pathways (ethylene, ABA, IAA and cytokinin), transcription factors (MYB, MYB-related, bHLH, bZIP, and WRKY), calcium signaling and glycolysis pathway to mitigating hypoxic stress in cucumber seedlings. Additionally, miRNA and their target genes were detected and predicted between treatments. The target genes of these miRNAs revealed that auxin, cellulose synthase, and mitochondrial ribosomal related genes (Csa2G315390, Csa6G141390, Csa4G053280, and Csa6G310480) probably play in the improvement of the hypoxic tolerance of cucumber seedlings through exogenous calcium application. In short, our data adds new information to the mechanism of exogenous calcium mitigation of hypoxic stress injury in cucumber seedlings at transcriptional and post-transcriptional levels.
PMID: 36684729
Front Plant Sci , IF:5.753 , 2022 , V13 : P1061747 doi: 10.3389/fpls.2022.1061747
Uninterrupted embryonic growth leading to viviparous propagule formation in woody mangrove.
Key Laboratory of the Ministry of Education for Coastal and Wetland Ecosystems, College of the Environment and Ecology, Xiamen University, Xiamen, Fujian, China.; Biomedical Sciences, College of Dental Medicine, Western University of Health Sciences, Pomona, CA, United States.
Vivipary is a rare sexual reproduction phenomenon where embryos germinate directly on the maternal plants. However, it is a common genetic event of woody mangroves in the Rhizophoraceae family. The ecological benefits of vivipary in mangroves include the nurturing of seedlings in harsh coastal and saline environments, but the genetic and molecular mechanisms of vivipary remain unclear. Here we investigate the viviparous embryo development and germination processes in mangrove Kandelia obovata by a transcriptomic approach. Many key biological pathways and functional genes were enriched in different tissues and stages, contributing to vivipary. Reduced production of abscisic acid set a non-dormant condition for the embryo to germinate directly. Genes involved in the metabolism of and response to other phytohormones (gibberellic acid, brassinosteroids, cytokinin, and auxin) are expressed precociously in the axis of non-vivipary stages, thus promoting the embryo to grow through the seed coat. Network analysis of these genes identified the central regulatory roles of LEC1 and FUS3, which maintain embryo identity in Arabidopsis. Moreover, photosynthesis related pathways were significantly up-regulated in viviparous embryos, and substance transporter genes were highly expressed in the seed coat, suggesting a partial self-provision and maternal nursing. We conclude that the viviparous phenomenon is a combinatorial result of precocious loss of dormancy and enhanced germination potential during viviparous seed development. These results shed light on the relationship between seed development and germination, where the continual growth of the embryo replaces a biphasic phenomenon until a mature propagule is established.
PMID: 36684724
J Agric Food Chem , IF:5.279 , 2022 Dec , V70 (51) : P16229-16240 doi: 10.1021/acs.jafc.2c07072
Novel Plant Growth Regulator Guvermectin from Plant Growth-Promoting Rhizobacteria Boosts Biomass and Grain Yield in Rice.
Key Laboratory of Agricultural Microbiology of Heilongjiang Province, Northeast Agricultural University, Harbin 150030, China.; State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing 100193, China.; State Key Laboratory of Phytochemistry and Plant Resources in West China, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650201, China.; Key Laboratory of Vector Biology and Pathogen Control of Zhejiang Province, College of Life Science, Huzhou University, Huzhou 313000, China.; Institute of Plant Protection, Hunan Academy of Agricultural Sciences, Changsha 410125, China.
Food is a fundamental human right, and global food security is threatened by crop production. Plant growth regulators (PGRs) play an essential role in improving crop yield and quality, and this study reports on a novel PGR, termed guvermectin (GV), isolated from plant growth-promoting rhizobacteria, which can promote root and coleoptile growth, tillering, and early maturing in rice. GV is a nucleoside analogue like cytokinin (CK), but it was found that GV significantly promoted root and hypocotyl growth, which is different from the function of CK in Arabidopsis. The Arabidopsis CK receptor triple mutant ahk2-2 ahk3-3 cre1-12 still showed a GV response. Moreover, GV led different growth-promoting traits from auxin, gibberellin (GA), and brassinosteroid (BR) in Arabidopsis and rice. The results from a four-year field trial involving 28 rice varieties showed that seed-soaking treatment with GV increased the yields by 6.2 to 19.6%, outperforming the 4.0 to 10.8% for CK, 1.6 to 16.9% for BR, and 2.2 to 7.1% for GA-auxin-BR mixture. Transcriptome analysis demonstrated that GV induced different transcriptome patterns from CK, auxin, BR, and GA, and SAUR genes may regulate GV-mediated plant growth and development. This study suggests that GV represents a novel PGR with a unique signal perception and transduction pathway in plants.
PMID: 36515163
Biology (Basel) , IF:5.079 , 2023 Jan , V12 (1) doi: 10.3390/biology12010095
The Strigolactone Pathway Is a Target for Modifying Crop Shoot Architecture and Yield.
Waite Research Institute, School of Agriculture Food & Wine, The University of Adelaide, Adelaide, SA 5064, Australia.; Australian Research Council Centre of Excellence in Plants for Space, The University of Adelaide, Adelaide, SA 5064, Australia.; Australian Research Council Training Centre for Future Crops Development, The University of Adelaide, Adelaide, SA 5064, Australia.; Australian Research Council Centre of Excellence for Plant Success in Nature and Agriculture, The University of Queensland, Brisbane, QLD 4072, Australia.
Due to their sessile nature, plants have developed the ability to adapt their architecture in response to their environment. Branching is an integral component of plant architecture, where hormonal signals tightly regulate bud outgrowth. Strigolactones (SLs), being a novel class of phytohormone, are known to play a key role in branching decisions, where they act as a negative regulator of bud outgrowth. They can achieve this by modulating polar auxin transport to interrupt auxin canalisation, and independently of auxin by acting directly within buds by promoting the key branching inhibitor TEOSINTE BRANCHED1. Buds will grow out in optimal conditions; however, when conditions are sub-optimal, SL levels increase to restrict branching. This can be a problem in agricultural applications, as reductions in branching can have deleterious effects on crop yield. Variations in promoter elements of key SL-related genes, such as IDEAL PLANT ARCHITECTURE1, have been identified to promote a phenotype with enhanced yield performance. In this review we highlight how this knowledge can be applied using new technologies to develop new genetic variants for improving crop shoot architecture and yield.
PMID: 36671787
Plant Cell Physiol , IF:4.927 , 2023 Jan doi: 10.1093/pcp/pcad007
Wound-induced rooting in plants - A big BIG ROle emerges for calcium and auxin.
Institute of Transformative Bio-Molecules (WPI-ITbM), Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8601 Japan.
PMID: 36688580
Plant Cell Physiol , IF:4.927 , 2023 Jan , V63 (12) : P2045 doi: 10.1093/pcp/pcac169
Editor's Note: The Impact of Tobamovirus Infection on Root Development Involves Induction of Auxin Response Factor 10a in Tomato.
PMID: 36625085
Plant Cell Physiol , IF:4.927 , 2023 Jan , V63 (12) : P1943-1953 doi: 10.1093/pcp/pcac150
Silicon Palliates Chromium Toxicity through the Formation of Root Hairs in Rice (Oryza sativa) Mediated by GSH and IAA.
Crop Nanobiology and Molecular Stress Physiology Lab, Amity Institute of Organic Agriculture, Amity University Uttar Pradesh, Sector-125, Noida 201313, India.; Department of Biotechnology, Motilal Nehru National Institute of Technology Allahabad, Prayagraj, UP 211004, India.; Department of Biology, Saint Joseph's University, University City Campus, 600 S. 43rd St., Philadelphia, PA 19104, USA.; Department of Stress, Development and Signaling in Plants, Group of Antioxidants, Free Radicals and Nitric Oxide in Biotechnology, Food and Agriculture, Estacion Experimental del Zaidin, Consejo Superior de Investigaciones Cientificas (CSIC), Profesor Albareda 1, Granada 18008, Spain.; Plant Physiology Laboratory, Department of Botany, C.M.P. Degree College, A Constituent Post Graduate College of University of Allahabad, Prayagraj 211002, India.
Along with the rapidly increasing environmental contamination by heavy metals, the exposure of plants to chromium has also magnified, resulting in a declined productivity. Hexavalent chromium [Cr(VI)], the most toxic form of Cr, brings about changes in plant processes at morpho-physiological and biochemical levels. However, silicon (Si) is known to mitigate the impact of abiotic stresses in plants. Here, we demonstrate Si-mediated alleviation of Cr(VI) toxicity and its effects on root hair formation in rice seedlings. Reduced glutathione (GSH) and indole-3 acetic acid (IAA, an important auxin) were assessed for their involvement in root hair formation after the application of Si to Cr(VI)-stressed plants, and our results confirmed their crucial significance in such developmental processes. The expression analysis of genes involved in GSH biosynthesis (OsGS2) and regeneration (OsGR1), and auxin biosynthesis (OsTAA1 and OsYUCCA1) and transport (OsAUX1 and OsPIN1) corroborated their positive role in Si-mediated root hair formation in Cr(VI)-stressed rice seedlings. Moreover, the results indicated that nitric oxide (NO) seems a probable but not fundamental component in Si-mediated formation of roots in rice during exposure to Cr(VI) stress. In this study, the indispensable role of GSH and IAA, redox homeostasis of GSH and IAA biosynthesis and transport are discussed with regard to Si-mediated formation of root hairs in rice under Cr(VI) stress. The results of the study suggest that Si is a protective agent against Cr(VI) stress in rice, and the findings can be used to develop Cr(VI) stress-tolerant varieties of rice with enhanced productivity.
PMID: 36264202
Plant Cell Physiol , IF:4.927 , 2023 Jan , V63 (12) : P1848-1856 doi: 10.1093/pcp/pcac149
Integration of Auxin, Brassinosteroid and Cytokinin in the Regulation of Rice Yield.
Department of Life Sciences, POSTECH Biotech Center, Pohang University of Science and Technology, 77 Cheongam-Ro, Namgu, Pohang-si 37673, South Korea.; Department of Botany, Hindu Girls College, Maharshi Dayanand University, Sonipat 131001, India.; Institute of Research and Development, Duy Tan University, 03 Quang Trung, Da Nang, TX 79409, Vietnam.; Department of Plant and Soil Science, Institute of Genomics for Crop Abiotic Stress Tolerance, Texas Tech University, Lubbock, TX 79409, USA.
Crop varieties with a high yield are most desirable in the present context of the ever-growing human population. Mostly, the yield traits are governed by a complex of numerous molecular and genetic facets modulated by various quantitative trait loci (QTLs). With the identification and molecular characterizations of yield-associated QTLs over recent years, the central role of phytohormones in regulating plant yield is becoming more apparent. Most often, different groups of phytohormones work in close association to orchestrate yield attributes. Understanding this cross talk would thus provide new venues for phytohormone pyramiding by editing a single gene or QTL(s) for yield improvement. Here, we review a few important findings to integrate the knowledge on the roles of auxin, brassinosteroid and cytokinin and how a single gene or a QTL could govern cross talk among multiple phytohormones to determine the yield traits.
PMID: 36255097
Plant Cell Physiol , IF:4.927 , 2023 Feb , V64 (1) : P80-93 doi: 10.1093/pcp/pcac142
Loss of MYB34 Transcription Factor Supports the Backward Evolution of Indole Glucosinolate Biosynthesis in a Subclade of the Camelineae Tribe and Releases the Feedback Loop in This Pathway in Arabidopsis.
Institute of Bioorganic Chemistry, Polish Academy of Sciences, Noskowskiego 12/14, Poznan 61-704, Poland.; Institute of Plant Genetics, Polish Academy of Sciences, Strzeszynska 34, Poznan 60-479, Poland.; Department of General Botany, Institute of Experimental Biology, Adam Mickiewicz University, Uniwersytetu Poznanskiego 6, Poznan 61-614, Poland.
Glucosinolates are specialized defensive metabolites characteristic of the Brassicales order. Among them, aliphatic and indolic glucosinolates (IGs) are usually highly abundant in species from the Brassicaceae family. The exceptions this trend are species representing a subclade of the Camelineae tribe, including Capsella and Camelina genera, which have reduced capacity to produce and metabolize IGs. Our study addresses the contribution of specific glucosinolate-related myeloblastosis (MYB) transcription factors to this unprecedented backward evolution of IG biosynthesis. To this end, we performed phylogenomic and functional studies of respective MYB proteins. The obtained results revealed weakened conservation of glucosinolate-related MYB transcription factors, including loss of functional MYB34 protein, in the investigated species. We showed that the introduction of functional MYB34 from Arabidopsis thaliana partially restores IG biosynthesis in Capsella rubella, indicating that the loss of this transcription factor contributes to the backward evolution of this metabolic pathway. Finally, we performed an analysis of the impact of particular myb mutations on the feedback loop in IG biosynthesis, which drives auxin overproduction, metabolic dysregulation and strong growth retardation caused by mutations in IG biosynthetic genes. This uncovered the unique function of MYB34 among IG-related MYBs in this feedback regulation and consequently in IG conservation in Brassicaceae plants.
PMID: 36222356
Plant Cell Physiol , IF:4.927 , 2023 Jan , V63 (12) : P1814-1825 doi: 10.1093/pcp/pcac138
Auxin Crosstalk with Reactive Oxygen and Nitrogen Species in Plant Development and Abiotic Stress.
Department of Botany, D D Pant Interdisciplinary Research Laboratory, University of Allahabad, Prayagraj-211002, India.; Crop Nanobiology and Molecular Stress Physiology Lab, Amity Institute of Organic Agriculture, Amity University Uttar Pradesh, Sector-125, Noida 201313, India.; Department of Biotechnology, Motilal Nehru National Institute of Technology, Allahabad, Prayagraj-211004, India.; Department of Botany, Plant Physiology Laboratory, CMP, Degree Collage, University of Allahabad, Prayagraj-211002, India.; Department of Biology, Technische Universitat Dresden, Dresden 01062, Germany.; Department of Biochemistry, Cell and Molecular Biology, Estacion Experimental del Zaidin, Consejo Superior de Investigaciones Cientificas (CSIC), C/Professor Albareda, 1, Granada 18008, Spain.
The phytohormone auxin acts as an important signaling molecule having regulatory functions during the growth and development of plants. Reactive oxygen species (ROS) are also known to perform signaling functions at low concentrations; however, over-accumulation of ROS due to various environmental stresses damages the biomolecules and cell structures and leads to cell death, and therefore, it can be said that ROS act as a double-edged sword. Nitric oxide (NO), a gaseous signaling molecule, performs a wide range of favorable roles in plants. NO displays its positive role in photomorphogenesis, root growth, leaf expansion, seed germination, stomatal closure, senescence, fruit maturation, mitochondrial activity and metabolism of iron. Studies have revealed the early existence of these crucial molecules during evolution. Moreover, auxin, ROS and NO together show their involvement in various developmental processes and abiotic stress tolerance. Redox signaling is a primary response during exposure of plants to stresses and shows a link with auxin signaling. This review provides updated information related to crosstalk between auxin, ROS and NO starting from their evolution during early Earth periods and their interaction in plant growth and developmental processes as well as in the case of abiotic stresses to plants.
PMID: 36208156
Plant Cell Physiol , IF:4.927 , 2023 Jan , V63 (12) : P1806-1813 doi: 10.1093/pcp/pcac084
Genetic and Hormonal Blueprint of Shoot-Borne Adventitious Root Development in Rice and Maize.
Department of Biosciences and Bioengineering, Indian Institute of Technology Roorkee, Roorkee, Uttarakhand 247667, India.
The evolution of root architecture in plants was a prerequisite for the absorption of water and minerals from the soil, and thus a major determinant of terrestrial plant colonization. Cereals have a remarkably complex root system consisting of embryonic primary roots and post-embryonic lateral roots and shoot-borne adventitious roots. Among grass species, rice adventitious roots (also called crown roots) are developed from compressed nodes at the stem base, whereas in maize, besides crown roots, several aboveground brace roots are also formed, thus adventitious root types display species-specific diversity. Despite being the backbone for the adult root system in monocots, adventitious roots are the least studied of all the plant organs. In recent times, molecular genetics, genomics and proteomics-based approaches have been utilized to dissect the mechanism of post-embryonic meristem formation and tissue patterning. Adventitious root development is a cumulative effect of the actions and interactions of crucial genetic and hormonal regulators. In this review, we provide a comprehensive view of the key regulators involved during the different stages of adventitious root development in two important crop plants, rice and maize. We have reviewed the roles of major phytohormones, microRNAs and transcription factors and their crosstalk during adventitious root development in these cereal crops.
PMID: 35713294
Plant Cell Physiol , IF:4.927 , 2023 Jan , V63 (12) : P1980-1993 doi: 10.1093/pcp/pcab179
The Impact of Tobamovirus Infection on Root Development Involves Induction of Auxin Response Factor 10a in Tomato.
Department of Plant Pathology and Weed Research, Agricultural Research Organization-The Volcani Institute, 68 HaMaccabim Road, P.O.B 15159, Rishon LeZion 7505101, Israel.; The Robert H. Smith Faculty of Agriculture, Food and Environment, the Hebrew University of Jerusalem, PO Box 12, Rehovot 761001, Israel.; Plant Sciences Institute, Agricultural Research Organization, The Volcani Institute, 68 HaMaccabim Road, P.O.B 15159, Rishon LeZion 7505101, Israel.
Plant viruses cause systemic diseases that severely impair plant growth and development. While the accumulation of viruses in the root system has long been established, little is known as to how viruses affect root architecture. Here, we examined how the emerging tobamovirus, tomato brown rugose fruit virus (ToBRFV), alters root development in tomato. We found that ToBRFV and tobacco mosaic virus both invaded root systems during the first week of infection. ToBRFV infection of tomato plants resulted in a significant decrease in root biomass and elongation and root-to-shoot ratio and a marked suppression of root branching. Mutation in RNA-dependent RNA polymerase 6 increased the susceptibility of tomato plants to ToBRFV, resulting in severe reduction of various root growth parameters including root branching. Viral root symptoms were associated with the accumulation of auxin response factor 10a (SlARF10a) transcript, a homolog of Arabidopsis ARF10, a known suppressor of lateral root development. Interestingly, loss-of-function mutation in SlARF10a moderated the effect of ToBRFV on root branching. In contrast, downregulation of sly-miR160a, which targets SlARF10a, was associated with constitutive suppression root branching independent of viral infection. In addition, overexpression of a microRNA-insensitive mutant of SlARF10a mimicked the effect of ToBRFV on root development, suggesting a specific role for SlARF10a in ToBRFV-mediated suppression of root branching. Taken together, our results provide new insights into the impact of tobamoviruses on root development and the role of ARF10a in the suppression of root branching in tomato.
PMID: 34977939
Plant Cell Physiol , IF:4.927 , 2023 Jan , V63 (12) : P1968-1979 doi: 10.1093/pcp/pcab155
Auxin-Responsive (Phospho)proteome Analysis Reveals Key Biological Processes and Signaling Associated with Shoot-Borne Crown Root Development in Rice.
Department of Biosciences and Bioengineering, Indian Institute of Technology, Roorkee, Uttarakhand 247667, India.; Department of Plant Biotechnology and Bioinformatics, Ghent University, Ghent 9052, Belgium.; VIB Center for Plant Systems Biology, Ghent 9052, Belgium.
The rice root system is primarily composed of shoot-borne adventitious/crown roots (ARs/CRs) that develop from the coleoptile base, and therefore, it is an excellent model system for studying shoot-to-root trans-differentiation process. We reveal global changes in protein and metabolite abundance and protein phosphorylation in response to an auxin stimulus during CR development. The liquid chromatography-tandem mass spectrometry (LC-MS/MS) and gas chromatography-mass spectrometry (GC-MS) analyses of developing crown root primordia (CRP) and emerged CRs identified 334 proteins and 12 amino acids, respectively, that were differentially regulated upon auxin treatment. Gene ontology enrichment analysis of global proteome data uncovered the biological processes associated with chromatin conformational change, gene expression and cell cycle that were regulated by auxin signaling. Spatial gene expression pattern analysis of differentially abundant proteins disclosed their stage-specific dynamic expression pattern during CRP development. Further, our tempo-spatial gene expression and functional analyses revealed that auxin creates a regulatory module during CRP development and activates ethylene biosynthesis exclusively during CRP initiation. Further, the phosphoproteome analysis identified 8,220 phosphosites, which could be mapped to 1,594 phosphoproteins and of which 66 phosphosites were differentially phosphorylated upon auxin treatment. Importantly, we observed differential phosphorylation of the cyclin-dependent kinase G-2 (OsCDKG;2) and cell wall proteins, in response to auxin signaling, suggesting that auxin-dependent phosphorylation may be required for cell cycle activation and cell wall synthesis during root organogenesis. Thus, our study provides evidence for the translational and post-translational regulation during CR development downstream of the auxin signaling pathway.
PMID: 34679169
Biomolecules , IF:4.879 , 2023 Feb , V13 (2) doi: 10.3390/biom13020299
The Role of a Cytokinin Antagonist in the Progression of Clubroot Disease.
Laboratory of Growth Regulators, Faculty of Science, Institute of Experimental Botany of the Czech Academy of Sciences, Palacky University, Slechtitelu 27, CZ-78371 Olomouc, Czech Republic.; Department of Biophysics, Faculty of Science, Palacky University, Slechtitelu 27, CZ-78371 Olomouc, Czech Republic.
Plasmodiophora brassicae is an obligate biotrophic pathogen causing clubroot disease in cruciferous plants. Infected plant organs are subject to profound morphological changes, the roots form characteristic galls, and the leaves are chlorotic and abscise. The process of gall formation is governed by timely changes in the levels of endogenous plant hormones that occur throughout the entire life cycle of the clubroot pathogen. The homeostasis of two plant hormones, cytokinin and auxin, appears to be crucial for club development. To investigate the role of cytokinin and auxin in gall formation, we used metabolomic and transcriptomic profiling of Arabidopsis thaliana infected with clubroot, focusing on the late stages of the disease, where symptoms were more pronounced. Loss-of-function mutants of three cytokinin receptors, AHK2, AHK3, and CRE1/AHK4, were employed to further study the homeostasis of cytokinin in response to disease progression; ahk double mutants developed characteristic symptoms of the disease, albeit with varying intensity. The most susceptible to clubroot disease was the ahk3 ahk4 double mutant, as revealed by measuring its photosynthetic performance. Quantification of phytohormone levels and pharmacological treatment with the cytokinin antagonist PI-55 showed significant changes in the levels of endogenous cytokinin and auxin, which was manifested by both enhanced and reduced development of disease symptoms in different genotypes.
PMID: 36830668
Rice (N Y) , IF:4.783 , 2023 Feb , V16 (1) : P9 doi: 10.1186/s12284-023-00626-3
Ubiquitin-Conjugating Enzyme OsUBC11 Affects the Development of Roots via Auxin Pathway.
State Key Laboratory of Black Soils Conservation and Utilization, Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, Harbin, China.; University of Chinese Academy of Sciences, Beijing, China.; Hinggan League Institute of Agricultural and Animal Husbandry Sciences, Hinggan League, 137400, Inner Mongolia, China.; Northeast Agricultural University, Harbin, China.; Hinggan League Institute of Agricultural and Animal Husbandry Sciences, Hinggan League, 137400, Inner Mongolia, China. xxjclean@126.com.; State Key Laboratory of Black Soils Conservation and Utilization, Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, Harbin, China. fangjun@iga.ac.cn.
Rice has 48 ubiquitin-conjugating enzymes, and the functions of most of these enzymes have not been elucidated. In the present study, a T-DNA insertional mutant named R164, which exhibited a significant decrease in the length of primary and lateral roots, was used as the experimental material to explore the potential function of OsUBC11. Analysis using the SEFA-PCR method showed that the T-DNA insertion was present in the promoter region of OsUBC11 gene, which encodes ubiquitin-conjugating enzyme (E2), and activates its expression. Biochemical experiments showed that OsUBC11 is a lysine-48-linked ubiquitin chain-forming conjugase. OsUBC11 overexpression lines showed the same root phenotypes. These results demonstrated that OsUBC11 was involved in root development. Further analyses showed that the IAA content of R164 mutant and OE3 line were significantly lower compared with wild-type Zhonghua11. Application of exogenous NAA restored the length of lateral and primary roots in R164 and OsUBC11 overexpression lines. Expression of the auxin synthesis regulating gene OsYUCCA4/6/7/9, the auxin transport gene OsAUX1, auxin/indole-3-acetic acid (Aux/IAA) family gene OsIAA31, auxin response factor OsARF16 and root regulator key genes, including OsWOX11, OsCRL1, OsCRL5 was significantly down-regulated in OsUBC11 overexpressing plants. Collectively, these results indicate that OsUBC11 modulates auxin signaling, ultimately affecting root development at the rice seedling stage.
PMID: 36808375
Plant Sci , IF:4.729 , 2023 Feb : P111638 doi: 10.1016/j.plantsci.2023.111638
SlGH3.15, a member of the GH3 gene family, regulates lateral root development and gravitropism response by modulating auxin homeostasis in tomato.
Key Laboratory of Horticultural Plant Biology, Ministry of Education, Huazhong Agricultural University, Wuhan, Hubei, 430070, P. R. China.; Vegetable Research Institute, Guangxi Academy of Agricultural Sciences, Nanning, Guangxi, 530007, P. R. China.; Department of Plant Sciences, University of Idaho, Moscow, Idaho, 83844, USA.; Key Laboratory of Horticultural Plant Biology, Ministry of Education, Huazhong Agricultural University, Wuhan, Hubei, 430070, P. R. China. Electronic address: zhangjunhng@mail.hzau.edu.cn.
Multiple Gretchen Hagen 3 (GH3) genes have been implicated in a range of processes in plant growth and development through their roles in maintaining hormonal homeostasis. However, there has only been limited study on the functions of GH3 genes in tomato (Solanum lycopersicum). In this work, we investigated the important function of SlGH3.15, a member of the GH3 gene family in tomato. Overexpression of SlGH3.15 led to severe dwarfism in both the above- and below-ground sections of the plant, accompanied by a substantial decrease in free IAA content and reduction in the expression of SlGH3.9, a paralog of SlGH3.15. Exogenous supply of IAA negatively affected the elongation of the primary root and partially restored the gravitropism defects in SlGH3.15-overexpression lines. While no phenotypic change was observed in the SlGH3.15 RNAi lines, double knockout lines of SlGH3.15 and SlGH3.9 were less sensitive to treatments with the auxin polar transport inhibitor. Overall, these findings revealed important roles of SlGH3.15 in IAA homeostasis and as a negative regulator of free IAA accumulation and lateral root formation in tomato.
PMID: 36796648
Plant Sci , IF:4.729 , 2023 Apr , V329 : P111625 doi: 10.1016/j.plantsci.2023.111625
A mutation in CsABCB19 encoding an ATP-binding cassette auxin transporter leads to erect and compact leaf architecture in cucumber (Cucumis sativus L.).
State Key Laboratory of Crop Genetics and Germplasm Enhancement, College of Horticulture, Nanjing Agricultural University, Nanjing 210095, China. Electronic address: 2018204029@njau.edu.cn.; State Key Laboratory of Crop Genetics and Germplasm Enhancement, College of Horticulture, Nanjing Agricultural University, Nanjing 210095, China. Electronic address: 2017204016@njau.edu.cn.; State Key Laboratory of Crop Genetics and Germplasm Enhancement, College of Horticulture, Nanjing Agricultural University, Nanjing 210095, China. Electronic address: 2019204035@njau.edu.cn.; State Key Laboratory of Crop Genetics and Germplasm Enhancement, College of Horticulture, Nanjing Agricultural University, Nanjing 210095, China. Electronic address: 2020104064@stu.njau.edu.cn.; State Key Laboratory of Crop Genetics and Germplasm Enhancement, College of Horticulture, Nanjing Agricultural University, Nanjing 210095, China. Electronic address: 2020104065@stu.njau.edu.cn.; State Key Laboratory of Crop Genetics and Germplasm Enhancement, College of Horticulture, Nanjing Agricultural University, Nanjing 210095, China. Electronic address: chunyancheng@njau.edu.cn.; State Key Laboratory of Crop Genetics and Germplasm Enhancement, College of Horticulture, Nanjing Agricultural University, Nanjing 210095, China. Electronic address: jfchen@njau.edu.cn.; State Key Laboratory of Crop Genetics and Germplasm Enhancement, College of Horticulture, Nanjing Agricultural University, Nanjing 210095, China. Electronic address: qflou@njau.edu.cn.
Leaf architecture, including leaf position and leaf morphology, is a critical component of plant architecture that directly determines plant appearance, photosynthetic utilization, and ultimate productivity. The mechanisms regulating leaf petiole angle and leaf flatness in cucumber remain unclear. In this study, we identified an erect and compact leaf architecture mutant (ecla) from an EMS (ethyl methanesulfonate) -mutagenized cucumber population, which exhibited erect petioles and crinkled leaves. Histological examination revealed significant phenotypic variation in ecla was associated with asymmetric cell expansion. MutMap sequencing combined with genetic mapping revealed that CsaV3_5G037960 is the causative gene for the ecla mutant phenotype. Through protein sequence alignment and Arabidopsis genetic complementation, we identified this gene as a functional direct homolog encoding the ATP-binding cassette transporter AtABCB19, hence named CsABCB19. A nonsynonymous mutation in the eleventh exon of CsABCB19 leads to premature termination of translation. The expression level of CsABCB19 in the ecla mutant was significantly reduced in all tissues compared to the wild type (WT). Transcriptome analysis revealed that auxin and polarity-related genes were significantly differentially expressed in mutant petioles and leaves, compared with those in WT. Auxin assay and exogenous treatment further demonstrated that CsABCB19 regulates leaf architecture by mediating auxin accumulation and transport. Our research is the first report describing the role of the ABCB19 transporter protein in auxin transport controlling cucumber leaf development. Furthermore, this study provides recent insights into the genetic mechanisms conferring morphological diversity and regulation of petiole angle and leaf flattening. DATA AVAILABILITY: The RNA-seq data in this study have been deposited in the NCBI SRA under BioProject accession number PRJNA874548.
PMID: 36758728
Plant Sci , IF:4.729 , 2023 Apr , V329 : P111606 doi: 10.1016/j.plantsci.2023.111606
pin2 mutant agravitropic root phenotype is conditional and nutrient-sensitive.
IPSiM, Univ Montpellier, CNRS, INRAE, Institut Agro, Montpellier, France.; Univ New Hampshire, Durham, USA.; IPSiM, Univ Montpellier, CNRS, INRAE, Institut Agro, Montpellier, France. Electronic address: benjamin.peret@cnrs.fr.
Plants have the capacity to sense and adapt to environmental factors using the phytohormone auxin as a major regulator of tropism and development. Among these responses, gravitropism is essential for plant roots to grow downward in the search for nutrients and water. We discovered a new mutant allele of the auxin efflux transporter PIN2 that revealed that pin2 agravitropic root mutants are conditional and nutrient-sensitive. We describe that nutrient composition of the medium, rather than osmolarity, can revert the agravitropic root phenotype of pin2. Indeed, on phosphorus- and nitrogen-deprived media, the agravitropic root defect was restored independently of primary root growth levels. Slow and fast auxin responses were evaluated using DR5 and R2D2 probes, respectively, and revealed a strong modulation by nutrient composition of the culture medium. We evaluated the role of PIN and AUX auxin transporters and demonstrated that neither PIN3 nor AUX1 are involved in this process. However, we observed the ectopic expression of PIN1 in the epidermis in the pin2 mutant background associated with permissive, but not restrictive, conditions. This ectopic expression was associated with a restoration of the asymmetric accumulation of auxin necessary for the reorientation of the root according to gravity. These observations suggest a strong regulation of auxin distribution by nutrients availability, directly impacting root's ability to drive their gravitropic response.
PMID: 36706868
Plant Sci , IF:4.729 , 2023 Feb , V327 : P111536 doi: 10.1016/j.plantsci.2022.111536
A 2-bp deletion in the protein kinase domain region of the ERECTA-like receptor kinase gene in cucumber results in short internode phenotype.
School of Horticulture and Landscape Architecture, Yangzhou University, Yangzhou, Jiangsu 225009, China; Joint International Research Laboratory of Agriculture and Agri-Product Safety, the Ministry of Education of China, Yangzhou University, Yangzhou, Jiangsu 225009, China.; School of Horticulture and Landscape Architecture, Yangzhou University, Yangzhou, Jiangsu 225009, China.; Jiangsu Key Laboratory for Horticultural Crop Genetic Improvement, Institute of Vegetable Crops, Jiangsu Academy of Agricultural Sciences, Nanjing, Jiangsu 210014, China.; School of Horticulture and Landscape Architecture, Yangzhou University, Yangzhou, Jiangsu 225009, China; Joint International Research Laboratory of Agriculture and Agri-Product Safety, the Ministry of Education of China, Yangzhou University, Yangzhou, Jiangsu 225009, China. Electronic address: xhchen@yzu.edu.cn.
Cucumber varieties with shortend internodes require less space than regular vining varieties, thus have great significance for germplasm improvement. Here, we found a novel spontaneous cucumber mutant si107 that exhibited short intenodes (si), smaller leaves, fruits, and seeds. The decrease in longitudinal cell length led to the shortened internodes of si107. The genetic analysis revealed a single recessive gene si-2 that was responsible for the mutation. Through multiple lines of evidence, we demonstrated that CsSI is the possible candidate gene for si-2, which encodes an ERECTA leucine-rich repeat receptor-like kinase. The shortened internode in si107 is attributed to a 2-bp deletion in the protein kinase domain region of this gene. The expression of CsSI was higher in the internodes, petioles, and fruit peels of si107 than in the wild type (WT). The transcriptome analysis between the si107 mutant and WT indicated that differentially expressed genes were significantly enriched in the plant hormone signal transduction pathway, in which auxin signal genes comprised the largest group, and all were downregulated in si107. Phytohormone quantitation confirmed that endogenous auxin levels in the stems of si107 were decreased. Our results provide new insights into the molecular mechanisms underlying the internode length control in cucumber.
PMID: 36402238
Plant Sci , IF:4.729 , 2023 Jan , V326 : P111522 doi: 10.1016/j.plantsci.2022.111522
Transcription factor NtWRKY33a modulates the biosynthesis of polyphenols by targeting NtMYB4 and NtHCT genes in tobacco.
China Tobacco Gene Research Center, Zhengzhou Tobacco Research Institute of CNTC, Zhengzhou 450001, China.; Technology Center, China Tobacco Hunan Industrial Co., Ltd., Changsha 410007, China.; Technology Center, China Tobacco Hunan Industrial Co., Ltd., Changsha 410007, China. Electronic address: hpj3508@126.com.; China Tobacco Gene Research Center, Zhengzhou Tobacco Research Institute of CNTC, Zhengzhou 450001, China. Electronic address: yangjun@ztri.com.cn.
There are abundant polyphenols in tobacco leaves mainly including chlorogenic acid (CGA), rutin, and scopoletin, which not only influence plant growth, development, and environmental adaptation, but also have a great impact on the industrial utilization of tobacco leaves. Few transcription factors regulating the biosynthesis of polyphenols have been identified in tobacco so far. In this study, two NtWRKY33 genes were identified from N. tabacum genome. NtWRKY33a showed higher transcriptional activity than NtWRKY33b, and encoded a nuclear localized protein. Overexpression and knock-out of NtWRKY33a gene revealed that NtWRKY33a inhibited the accumulation of rutin, scopoletin, and total polyphenols, but meanwhile promoted the biosynthesis of CGA. Chromatin immunoprecipitation and Dual-Luc assays indicated that NtWRKY33a could directly bind to the promoters of NtMYB4 and NtHCT, and thus induced the transcription of these two genes. The contents of polyphenols in ntwrky33a, ntmy4, and ntwrky33a/ntmyb4 mutants further confirmed that the repression of NtWRKY33a on the biosynthesis of rutin, scopoletin, and total polyphenols depends on the activity of NtMYB4. Moreover, the promotion of NtHCT by NtWRKY33a modulates the distribution of metabolism flux into the synthesis of CGA. Ectopic expression of NtWRKY33a inhibit the expression of NtSAUR14, NtSAUR59, NtSAUR66, NtIAA4, NtIAA17, and NtIAA19 genes, indicating that NtWRKY33a might be involved in the regulation of plant auxin response. Our study revealed new functions of NtWRKY33a in regulating the synthesis of polyphenols, and provided a promising target for manipulating polyphenols contents in tobacco.
PMID: 36332766
Plant Cell Rep , IF:4.57 , 2023 Feb doi: 10.1007/s00299-023-02990-2
An EMS-induced allele of the brachytic2 gene can reduce plant height in maize.
National Engineering Laboratory of Crop Stress Resistance Breeding, School of Life Sciences, Anhui Agricultural University, Hefei, 230036, China.; Key Laboratory of Breeding Engineering of Anhui Province, School of Life Sciences, Anhui Agricultural University, Hefei, 230036, China.; National Engineering Laboratory of Crop Stress Resistance Breeding, School of Life Sciences, Anhui Agricultural University, Hefei, 230036, China. mqqmmq@126.com.; Key Laboratory of Breeding Engineering of Anhui Province, School of Life Sciences, Anhui Agricultural University, Hefei, 230036, China. mqqmmq@126.com.
D129 is an EMS-induced mutant with dwarf phenotype, which has important breeding potential to cultivate new varieties suitable for high-density planting in maize Plant height is one of the important agronomic traits that affecting maize planting density, identification of superior dwarf mutants can provide important genetic materials for breeding new varieties suitable for high-density planting. In this study, we identified a dwarf mutant, d129, from maize EMS-induced mutant population. Gene mapping indicated that a G-to-A transition in the second exon of the br2 gene was responsible for the dwarf phenotype of the d129 mutant using MutMap method, which was further validated through allelism testing. Compared with WT plants, the average plant height and ear height of d129 were reduced by 26.67% and 39.43%, respectively, mainly due to a decrease in internode length. Furthermore, the d129 mutant exhibited increased internode diameter, which is important for increasing planting density due to the lodging resistance may be enhanced. Endogenous hormone measurement demonstrated that the contents of IAA and GA3 in the internode of the mutant were significantly lower than that of WT plants. RNA-seq analysis indicated that at least fifteen auxin-responsive and signaling-related genes exhibited differential expression, and some genes involved in cell development and other types of hormone signaling pathways, were also identified from the differential expressed genes. These genes may be related to the reduced hormone contents and decreased elongation of internode cells of the d129 mutant. Our study provided a novel dwarf mutant which can be applied in maize breeding to cultivate new varieties suitable for high-density planting.
PMID: 36754893
Physiol Plant , IF:4.5 , 2023 Feb : Pe13878 doi: 10.1111/ppl.13878
Insights into the Environmental Factors Shaping Lateral Root Development.
School of Life Sciences, Jiangsu University, Zhenjiang, Jiangsu, China.
Roots are important organs of plants. Plants rely on roots for water, nutrients and organic salts. In the whole root system, lateral roots (LRs) account for a large proportion and are critical to the development of the plant. Many environmental factors affect LR development. Therefore, a systematic understanding of these factors can provide a theoretical basis for creating optimal growth conditions for plants. In this paper, the factors affecting LR development are systematically and comprehensively summarized, and the molecular mechanism and regulatory network of LR development are described. Changes in the external environment not only lead to hormone homeostasis in plants but also affect the composition and activity of rhizosphere microbial communities, which in turn affect plants' nitrogen and phosphorus uptake and growth dynamics. LR development is influenced by hormone levels and external environment. In particular, auxin and ABA coordinate with each other to maintain normal LR development. Of course, changes in the external environment are also important for root development, and they affect the intrinsic hormone levels of plants by affecting the accumulation and transport of hormones. For example, nitrogen, phosphorus, ROS, NO, water, drought, light and rhizosphere microorganisms affect LR development and plant tolerance in a variety of ways, including regulating hormone levels. This review summarizes the factors affecting LR development and the regulatory network and points out the direction for future research. This article is protected by copyright. All rights reserved.
PMID: 36808102
Nitric Oxide , IF:4.427 , 2023 Jan , V130 : P36-57 doi: 10.1016/j.niox.2022.11.004
Say "NO" to plant stresses: Unravelling the role of nitric oxide under abiotic and biotic stress.
Department of Zoology, Guru Nanak Dev University, Amritsar, 143005, Punjab, India. Electronic address: deepdhaka415@gmail.com.; Department of Zoology, Guru Nanak Dev University, Amritsar, 143005, Punjab, India. Electronic address: ohri_puja_11@rediffmail.com.
Nitric oxide (NO) is a diatomic gaseous molecule, which plays different roles in different strata of organisms. Discovered as a neurotransmitter in animals, NO has now gained a significant place in plant signaling cascade. NO regulates plant growth and several developmental processes including germination, root formation, stomatal movement, maturation and defense in plants. Due to its gaseous state, it is unchallenging for NO to reach different parts of cell and counterpoise antioxidant pool. Various abiotic and biotic stresses act on plants and affect their growth and development. NO plays a pivotal role in alleviating toxic effects caused by various stressors by modulating oxidative stress, antioxidant defense mechanism, metal transport and ion homeostasis. It also modulates the activity of some transcriptional factors during stress conditions in plants. Besides its role during stress conditions, interaction of NO with other signaling molecules such as other gasotransmitters (hydrogen sulfide), phytohormones (abscisic acid, salicylic acid, jasmonic acid, gibberellin, ethylene, brassinosteroids, cytokinins and auxin), ions, polyamines, etc. has been demonstrated. These interactions play vital role in alleviating plant stress by modulating defense mechanisms in plants. Taking all these aspects into consideration, the current review focuses on the role of NO and its interaction with other signaling molecules in regulating plant growth and development, particularly under stressed conditions.
PMID: 36460229
Sci Rep , IF:4.379 , 2023 Jan , V13 (1) : P1488 doi: 10.1038/s41598-023-28084-3
Comparative proteomic analysis identified proteins and the phenylpropanoid biosynthesis pathway involved in the response to ABA treatment in cotton fiber development.
Hainan Key Laboratory for Sustainable Utilization of Tropical Bioresources, College of Tropical Crops, Hainan University, Haikou, 570228, China.; State Key Laboratory of Cotton Biology, School of Life Sciences, Henan University, Kaifeng, China.; Hainan Key Laboratory for Sustainable Utilization of Tropical Bioresources, College of Tropical Crops, Hainan University, Haikou, 570228, China. yhding@hainanu.edu.cn.; Hainan Yazhou Bay Seed Laboratory, Sanya Nanfan Research Institute of Hainan University, Sanya, China. yhding@hainanu.edu.cn.; Hainan Key Laboratory for Sustainable Utilization of Tropical Bioresources, College of Tropical Crops, Hainan University, Haikou, 570228, China. huhaiyan@hainanu.edu.cn.; Hainan Yazhou Bay Seed Laboratory, Sanya Nanfan Research Institute of Hainan University, Sanya, China. huhaiyan@hainanu.edu.cn.
Abscisic acid (ABA) is a plant hormone that plays an important role in cotton fiber development. In this study, the physiological changes and proteomic profiles of cotton (Gossypium hirsutum) ovules were analyzed after 20 days of ABA or ABA inhibitor (ABAI) treatment. The results showed that compared to the control (CK), the fiber length was significantly decreased under ABA treatment and increased under ABAI treatment. Using a tandem mass tags-based quantitative technique, the proteomes of cotton ovules were comprehensively analyzed. A total of 7321 proteins were identified, of which 365 and 69 differentially accumulated proteins (DAPs) were identified in ABA versus CK and ABAI versus CK, respectively. Specifically, 345 and 20 DAPs were up- and down-regulated in the ABA group, and 65 and 4 DAPs were up- and down-regulated in the ABAI group, respectively. The DAPs in the ABA group were mainly enriched in the biosynthesis of secondary metabolites, phenylpropanoid biosynthesis and flavonoid secondary metabolism, whereas the DAPs in the ABAI group were mainly enriched in the indole alkaloid biosynthesis and phenylpropanoid biosynthesis pathways. Moreover, 9 proteins involved in phenylpropanoid biosynthesis were upregulated after ABA treatment, suggesting that this pathway might play important roles in the response to ABA, and 3 auxin-related proteins were upregulated, indicating that auxin might participate in the regulation of fiber development under ABAI treatment.
PMID: 36707547
Plant Physiol Biochem , IF:4.27 , 2023 Feb , V195 : P362-374 doi: 10.1016/j.plaphy.2023.01.006
Genome-wide analysis of the SAUR gene family and function exploration of DlSAUR32 during early longan somatic embryogenesis.
Institute of Horticultural Biotechnology, Fujian Agriculture and Forestry University, Fuzhou, Fujian, 350002, China.; Institute of Horticultural Biotechnology, Fujian Agriculture and Forestry University, Fuzhou, Fujian, 350002, China. Electronic address: buliang84@163.com.
The early auxin responsive small auxin up-regulated RNA (SAUR) family is an important gene family in the auxin signal transduction pathway. This study focused on the regulatory mechanism of DlSAUR genes during early somatic embryogenesis (SE) and its response to hormone treatment and abiotic stress. Mining of the available Dimocarpus longan Lour. (D. longan) genome sequence yielded 68 putative SAUR genes. Transcript profiles based on RNA-seq data showed that most of the 24 detected DlSAUR genes were highly expressed in the globular embryos (GE) (10) and most of them responded to heat stress and 2,4-D treatment. The results of qRT-PCR showed that most of DlSAUR genes were up-regulated under auxin inhibitor N-1-naphthylphthalamic acid (NPA) and auxin indole-3-acetic acid (IAA) treatments. Moreover, NPA could promote longan SE. The assay for ATAC-seq data analysis showed that chromatin accessibility of 19 of the 24 DlSAUR genes were open during early SE, and most DlSAUR genes differentially expressed during early SE were not associated with H3K4me1 signal enrichment. The DlSAUR32 was selected for subcellular localization and RNA-seq analysis, which encode a cell nuclear-localized protein. Dual-luciferase assays and transient transformation showed that the transcription factors (TFs) DlWRKY75-1 and DlWRKY75-2 might bind to the DlSAUR32 promoters to inhibition gene transcription. Transient overexpression of DlWRKY75-1 and DlWRKY75-2 decreased IAA content in N. benthamiana leaves. Thus, the regulatory network composed of DlSAUR32 and its related TFs may regulate the early longan SE and be involved in the auxin response regulatory pathway of longan.
PMID: 36682137
Plant Physiol Biochem , IF:4.27 , 2023 Feb , V195 : P330-340 doi: 10.1016/j.plaphy.2023.01.002
Tomato (Solanum lycopersicum) WRKY23 enhances salt and osmotic stress tolerance by modulating the ethylene and auxin pathways in transgenic Arabidopsis.
Plant Gene Expression Lab, CSIR-National Botanical Research Institute, Lucknow, 226001, India.; Plant Gene Expression Lab, CSIR-National Botanical Research Institute, Lucknow, 226001, India; Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, 201002, India.; Plant Gene Expression Lab, CSIR-National Botanical Research Institute, Lucknow, 226001, India; Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, 201002, India. Electronic address: va.sane@nbri.res.in.
Osmotic stress is one of the biggest problems in agriculture, which adversely affects crop productivity. Plants adopt several strategies to overcome osmotic stresses that include transcriptional reprogramming and activation of stress responses mediated by different transcription factors and phytohormones. We have identified a WRKY transcription factor from tomato, SlWRKY23, which is induced by mannitol and NaCl treatment. Over-expression of SlWRKY23 in transgenic Arabidopsis enhances osmotic stress tolerance to mannitol and NaCl and affects root growth and lateral root number. Transgenic Arabidopsis over-expressing SlWRKY23 showed reduced electrolyte leakage and higher relative water content than Col-0 plants upon mannitol and NaCl treatment. These lines also showed better membrane integrity with lower MDA content and higher proline content than Col-0. Responses to mannitol were governed by auxin as treatment with TIBA (auxin transport inhibitor) negatively affected the osmotic tolerance in transgenic lines by inhibiting lateral root growth. Similarly, responses to NaCl were controlled by ethylene as treatment with AgNO(3) (ethylene perception inhibitor) inhibited the stress response to NaCl by suppressing primary and lateral root growth. The study shows that SlWRKY23, a osmotic stress inducible gene in tomato, imparts tolerance to mannitol and NaCl stress through interaction of the auxin and ethylene pathways.
PMID: 36669348
Plant Physiol Biochem , IF:4.27 , 2023 Feb , V195 : P193-205 doi: 10.1016/j.plaphy.2023.01.010
Polyamine metabolizing rhizobacteria Pseudomonas sp. GBPI_506 modulates hormone signaling to enhance lateral roots and nicotine biosynthesis in Nicotiana benthamiana.
Biotechnology Division, CSIR-Institute of Himalayan Bioresource Technology, Palampur, 176061, Himachal Pradesh, India. Electronic address: r.jain@uva.nl.; Biotechnology Division, CSIR-Institute of Himalayan Bioresource Technology, Palampur, 176061, Himachal Pradesh, India; Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, 201002, Uttar Pradesh, India. Electronic address: pari169396@gmail.com.; Biotechnology Division, CSIR-Institute of Himalayan Bioresource Technology, Palampur, 176061, Himachal Pradesh, India. Electronic address: shwetaguleria000@gmail.com.; Graphic Era Deemed to be University, Dehradun, 248002, Uttarakhand, India. Electronic address: anitapandey333@gmail.com.; Biotechnology Division, CSIR-Institute of Himalayan Bioresource Technology, Palampur, 176061, Himachal Pradesh, India. Electronic address: sanjaykumar@ihbt.res.in.
Beneficial rhizobacteria in the soil are important drivers of plant health and growth. In this study, we provide the draft genome of a root colonizing and auxin-producing Pseudomonas sp. strain GBPI_506. The bacterium was investigated for its contribution in the growth of Nicotiana benthamiana (Nb) and biosynthesis of nicotine. The bacterium showed chemotaxis towards root exudates potentially mediated by putrescine, a polyamine compound, to colonize the roots of Nb. Application of the bacterium with the roots of Nb, increased plant biomass and total soluble sugars in the leaves, and promoted lateral root (LR) development as compared to the un-inoculated plants. Confocal analysis using transgenic (DR5:GFP) Arabidopsis showed increased auxin trafficking in the LR of inoculated plants. Upregulation of nicotine biosynthesis genes and genes involved in salicylic acid (SA) and jasmonic acid (JA) signaling in the roots of inoculated plants suggested increased nicotine biosynthesis as a result of bacterial application. An increased JA content in roots and nicotine accumulation in leaves provided evidence on JA-mediated upregulation of nicotine biosynthesis in the bacterized plants. The findings suggested that the bacterial root colonization triggered networking between auxin, SA, and JA to facilitate LR development leading to enhanced plant growth and nicotine biosynthesis in Nb.
PMID: 36641943
Plant Physiol Biochem , IF:4.27 , 2023 Jan , V194 : P685-695 doi: 10.1016/j.plaphy.2022.12.018
The plant specific SHORT INTERNODES/STYLISH (SHI/STY) proteins: Structure and functions.
School of Life Sciences, Jiangsu University, Zhenjiang, 212013, Jiangsu, China.; School of Life Sciences, Jiangsu University, Zhenjiang, 212013, Jiangsu, China. Electronic address: cjinfor@163.com.
Plant specific SHORT INTERNODES/STYLISH (SHI/STY) protein is a transcription factor involved in the formation and development of early lateral organs in plants. However, research on the SHI/STY protein family is not focused enough. In this article, we review recent studies on SHI/STY genes and explore the evolution and structure of SHI/STY. The biological functions of SHI/STYs are discussed in detail in this review, and the application of each biological function to modern agriculture is discussed. All SHI/STY proteins contain typical conserved RING-like zinc finger domain and IGGH domain. SHI/STYs are involved in the formation and development of lateral root, stem extension, leaf morphogenesis, and root nodule development. They are also involved in the regulation of pistil and stamen development and flowering time. At the same time, the regulation of some GA, JA, and auxin signals also involves these family proteins. For each aspect, unanswered or poorly understood questions were identified to help define future research areas. This review will provide a basis for further functional study of this gene family.
PMID: 36565613
Plant Physiol Biochem , IF:4.27 , 2023 Jan , V194 : P182-192 doi: 10.1016/j.plaphy.2022.11.018
Nitric oxide acts as an inducer of Strategy-I responses to increase Fe availability and mobilization in Fe-starved broccoli (Brassica oleracea var. oleracea).
Department of Genetics, University of Georgia, GA 30602, USA; Molecular Plant Physiology Laboratory, University of Rajshahi, Rajshahi, 6205, Bangladesh. Electronic address: ahmad.kabir@uga.edu.; Molecular Plant Physiology Laboratory, University of Rajshahi, Rajshahi, 6205, Bangladesh.; Grassland and Forage Division, National Institute of Animal Science, Rural Development Administration, Cheonan, 31000, Republic of Korea.; Plant Nutrition Laboratory, Institute of Agricultural and Nutritional Sciences, Martin Luther University Halle-Wittenberg, Halle (Saale), Germany.
Iron (Fe) deficiency causes reduced growth and yield in broccoli. This study elucidates how sodium nitroprusside (SNP), known as nitric oxide (NO) donor, mitigates the retardation caused by Fe deficiency in broccoli. The SNP caused substantial nitric oxide accumulation in the roots of Fe-deficient plants, which resulted in a significant improvement in chlorophyll levels, photosynthetic efficiency, and morphological growth parameters, showing that it has a favorable influence on recovering broccoli health. Ferric reductase activity and the expression of BoFRO1 (ferric chelate reductase) gene in roots were consistently increased by SNP under Fe deficiency, which likely resulted in increased Fe mobilization. Furthermore, proton (H(+)) extrusion and BoHA2 (H(+)-ATPase 2) expression were significantly increased, suggesting that they may be involved in lowering rhizospheric pH to restore Fe mobilization in roots of bicarbonate-treated broccoli plants. The levels of Fe in root and shoot tissues and the expression of BoIRT1 (Fe-regulated transporter) both increased dramatically after SNP supplementation under Fe deprivation. Furthermore, SNP-induced increase in citrate and malate concentrations suggested a role of NO in improved Fe chelation in Fe-deficient broccoli. A NO scavenger (cPTIO) ceased the elevated FCR activity and IAA (indole-3-acetic acid) concentration in Fe-starved plants treated with SNP. These findings suggest that SNP may play a role in initiating Fe availability by elevated IAA concentration and BoEIR1 (auxin efflux carrier) expression in the roots of broccoli during Fe shortage. Therefore, SNP may improve Fe availability and mobilization by increasing Strategy-I Fe uptake pathways, which may help broccoli tolerate Fe deficiency.
PMID: 36423388
Environ Sci Pollut Res Int , IF:4.223 , 2023 Jan , V30 (5) : P13711-13725 doi: 10.1007/s11356-022-23134-1
Effects of elevated CO2 concentration and temperature on the mixed-culture grown wild mustard (Sinapis arvensis L.) response to auxin herbicide.
Department of Environmental Sciences, Vytautas Magnus University, Universiteto 10-307, Akademija, 53361, Kaunas District, Lithuania. jurate.zaltauskaite@vdu.lt.; Department of Environmental Sciences, Vytautas Magnus University, Universiteto 10-307, Akademija, 53361, Kaunas District, Lithuania.
Recently, there has been growing concern over the potential impact of CO(2) concentration and temperature on herbicide efficacy. The aim of the study was to examine the influence of single elevated CO(2) (400 vs. 800 ppm) and elevated CO(2) in combination with temperature (21 degrees C vs. 25 degrees C) on the effects of auxin herbicide 4-chloro-2-methylphenoxyacetic acid (MCPA) (0.5-2 x field recommended rate) to wild mustard (Sinapis arvensis L.) grown in mixed-culture with spring barley (Hordeum vulgare L.). MCPA had a detrimental effect on aboveground and belowground biomass, content of chlorophylls, enzymatic and non-enzymatic antioxidants and induced oxidative stress. The significant decline in photosynthetic rate, stomatal conductance and transpiration with MCPA dose was detected. Elevated CO(2) reinforced MCPA efficacy on S. arvensis: sharper decline in biomass, photosynthetic rate and antioxidant enzymes and more pronounced lipid peroxidation were detected. Under elevated CO(2) and temperature, MCPA efficacy to control S. arvensis dropped due to herbicide dilution because of increased root:shoot ratio, higher activity of antioxidants and less pronounced oxidative damage. Reinforced MCPA impact on weeds under elevated CO(2) resulted in higher H. vulgare biomass, while decreased MCPA efficacy under elevated CO(2) and temperature reduced H. vulgare biomass.
PMID: 36136189
BMC Plant Biol , IF:4.215 , 2023 Feb , V23 (1) : P90 doi: 10.1186/s12870-023-04102-4
Comparative analysis of the transcriptome during single-seed formation of Castanea henryi: regulation of starch metabolism and endogenous hormones.
Key Laboratory of Cultivation and Protection for Non-Wood Forest Trees, Ministry of Education, Central South University of Forestry and Technology, Changsha, 410004, China.; Key Lab of Non-Wood Forest Products of State Forestry Administration, Central South University of Forestry and Technology, Changsha, 410004, China.; Hunan Botanical Garden, Changsha, 410116, China.; Key Laboratory of Cultivation and Protection for Non-Wood Forest Trees, Ministry of Education, Central South University of Forestry and Technology, Changsha, 410004, China. fan_xiaoming001@163.com.; Key Lab of Non-Wood Forest Products of State Forestry Administration, Central South University of Forestry and Technology, Changsha, 410004, China. fan_xiaoming001@163.com.; Key Laboratory of Cultivation and Protection for Non-Wood Forest Trees, Ministry of Education, Central South University of Forestry and Technology, Changsha, 410004, China. yuan-deyi@163.com.; Key Lab of Non-Wood Forest Products of State Forestry Administration, Central South University of Forestry and Technology, Changsha, 410004, China. yuan-deyi@163.com.
BACKGROUND: In seed plants, the ovule is the precursor to the seed. The process of ovule development and differentiation is regulated by multiple factors, including starch metabolism and endogenous hormones. Castanea henryi produces nuts with high nutritional value. However, the high proportion of empty buds restricts the commercial use of the tree. Previous studies have shown that the empty bud phenotype is closely related to ovule abortion. If none of the ovules in the ovary expand rapidly and develop in 7-8 weeks after pollination, an empty bud will form. Therefore, we studied the development and molecular mechanisms underlying single seed formation in C. henryi. RESULTS: We found that 49 days after pollination (DAP) is a critical period for the formation of fertile and abortive ovules. The morphology and starch distribution of the fertile and abortive ovules differed significantly at 49 DAP. The fertile ovules were smooth and round in appearance, with a large amount of starch. In contrast, abortive ovules were smaller with only a small amount of starch. The embryo sac of the abortive ovule proceeded to develop abnormally, and the entire ovule lacked starch. We identified 37 candidate genes involved in metabolism with potential roles in the regulation of starch levels. Three ADP-glucose pyrophosphorylase (AGPase) genes, one granule-bound starch synthase (GBSS) gene, and two beta-amylase genes could affect starch accumulation. The levels of auxin, cytokinins, gibberellins, and jasmonic acid in fertile ovules were higher than those in abortive ovules. In addition, the levels of endogenous abscisic acid and salicylic acid in abortive ovules were higher than those in fertile ovules of the same age, consistent with the expression patterns of genes related to the synthesis of abscisic and salicylic acid and signal transduction. We identified and mapped the differentially expressed genes associated with hormone synthesis and signal transduction. CONCLUSIONS: These results improve our general understanding of the molecular mechanisms underlying single seed development in C. henryi and the phenomenon of empty buds, providing directions for future research.
PMID: 36782110
BMC Plant Biol , IF:4.215 , 2023 Feb , V23 (1) : P74 doi: 10.1186/s12870-023-04087-0
Auxin efflux carrier ZmPIN1a modulates auxin reallocation involved in nitrate-mediated root formation.
State Key Laboratory of Plant Physiology and Biochemistry, College of Agronomy and Biotechnology, China Agricultural University, Beijing, 100193, China.; Shandong Academy of Agricultural Sciences, Jinan, Shandong, China.; College of Resources and Environmental Science, China Agricultural University, Beijing, 100193, China.; Center for Crop Functional Genomics and Molecular Breeding, China Agricultural University, Beijing, 100193, China.; State Key Laboratory of Plant Physiology and Biochemistry, College of Agronomy and Biotechnology, China Agricultural University, Beijing, 100193, China. zmc1214@163.com.
BACKGROUND: Auxin plays a crucial role in nitrate (NO(3)(-))-mediated root architecture, and it is still unclear that if NO(3)(-) supply modulates auxin reallocation for regulating root formation in maize (Zea mays L.). This study was conducted to investigate the role of auxin efflux carrier ZmPIN1a in the root formation in response to NO(3)(-) supply. RESULTS: Low NO(3)(-) (LN) promoted primary root (PR) elongation, while repressed the development of lateral root primordia (LRP) and total root length. LN modulated auxin levels and polar transport and regulated the expression of auxin-responsive and -signaling genes in roots. Moreover, LN up-regulated the expression level of ZmPIN1a, and overexpression of ZmPIN1a enhanced IAA efflux and accumulation in PR tip, while repressed IAA accumulation in LRP initiation zone, which consequently induced LN-mediated PR elongation and LR inhibition. The inhibition rate of PR length, LRP density and number of ZmPIN1a-OE plants was higher than that of wild-type plants after auxin transport inhibitor NPA treatment under NN and LN conditions, and the degree of inhibition of root growth in ZmPIN1a-OE plants was more obvious under LN condition. CONCLUSION: These findings suggest that ZmPIN1a was involved in modulating auxin levels and transport to alter NO(3)(-)-mediated root formation in maize.
PMID: 36737696
BMC Plant Biol , IF:4.215 , 2023 Jan , V23 (1) : P35 doi: 10.1186/s12870-022-04025-6
Responses of roots and rhizosphere of female papaya to the exogenous application of GA(3).
Center for Genomics and Biotechnology, Fujian Provincial Key Laboratory of Haixia Applied Plant Systems Biology, Fujian Agriculture and Forestry University, Fuzhou, 350002, Fujian, China.; Key Laboratory of Sugarcane Biology and Genetic Breeding, Ministry of Agriculture, Fujian Agriculture and Forestry University, Fuzhou, 350002, China.; Center for Genomics and Biotechnology, Fujian Provincial Key Laboratory of Haixia Applied Plant Systems Biology, Fujian Agriculture and Forestry University, Fuzhou, 350002, Fujian, China. rayming@illinois.edu.
Exogenous GAs have an indeterminate effect on root development. Our current study used female papaya to reveal how the roots and rhizosphere respond to the exogenous application of GA(3) by investigating the transcriptome profile in roots, metabolic profile and microbial community in both roots and rhizosphere of GA(3)-treated and control female papaya. The results demonstrated that exogenous GA(3) treatment enhanced female papaya lateral root development, which gave plants physical advantages of water and nutrient uptake. In addition, it was likely that GA(3) spraying in papaya shoot apices increased the level of auxin, which was transported to roots by CpPIN1, where auxin upregulated CpLBD16 and repressed CpBP to promote the lateral root initiation and development. In papaya roots, corresponding transporters (CpTMT3, CpNRT1:2, CpPHT1;4, CpINT2, CpCOPT2, CpABCB11, CpNIP4;1) were upregulated and excretion transporters were downregulated such as CpNAXT1 for water and nutrients uptake with exogenous GA(3) application. Moreover, in GA(3)-treated papaya roots, CpALS3 and CpMYB62 were downregulated, indicating a stronger abiotic resistance to aluminum toxic and phosphate starvation. On the other hand, BRs and JAs, which involve in defense responses, were enriched in the roots and rhizosphere of GA(3)-treated papayas. The upregulation of the two hormones might result in the reduction of pathogens in roots and rhizosphere such as Colletotrichum and Verticillium. GA(3)-treated female papaya increased the abundance of beneficial bacteria species including Mycobacterium, Mitsuaria, and Actinophytocola, but decreased that of the genera Candidatus and Bryobacter for that it required less nitrate. Overall, the roots and rhizosphere of female papaya positively respond to exogenous application of GA(3) to promote development and stress tolerance. Treatment of female papaya with GA3 might result in the promotion of lateral root formation and development by upregulating CpLBD16 and downregulating CpBP. GA(3)-treated papaya roots exhibited feedback control of brassinolide and jasmonate signaling in root development and defense. These findings revealed complex response to a growth hormone treatment in papaya roots and rhizosphere and will lead to investigations on the impact of other plant hormones on belowground development in papaya.
PMID: 36642722
BMC Plant Biol , IF:4.215 , 2023 Jan , V23 (1) : P31 doi: 10.1186/s12870-023-04055-8
Genome-wide identification and expression analysis of the SAUR gene family in foxtail millet (Setaria italica L.).
College of Agriculture, Henan University of Science and Technology, Luoyang, 471000, Henan, People's Republic of China.; Henan Academy of Agriculture Sciences, Cereal Crops Institute, Zhengzhou, 450002, Henan, People's Republic of China.; Luoyang Academy of Agriculture and Forestry Sciences, Sweet Potato and Millet Institute, , Luoyang, 471023, Henan, People's Republic of China.; Henan Academy of Agriculture Sciences, Cereal Crops Institute, Zhengzhou, 450002, Henan, People's Republic of China. lijunxia@126.com.
BACKGROUND: Auxin performs important functions in plant growth and development processes, as well as abiotic stress. Small auxin-up RNA (SAUR) is the largest gene family of auxin-responsive factors. However, the knowledge of the SAUR gene family in foxtail millet is largely obscure. RESULTS: In the current study, 72 SiSAUR genes were identified and renamed according to their chromosomal distribution in the foxtail millet genome. These SiSAUR genes were unevenly distributed on nine chromosomes and were classified into three groups through phylogenetic tree analysis. Most of the SiSAUR members from the same group showed similar gene structure and motif composition characteristics. Analysis of cis-acting elements showed that many hormone and stress response elements were identified in the promoter region of SiSAURs. Gene replication analysis revealed that many SiSAUR genes were derived from gene duplication events. We also found that the expression of 10 SiSAURs was induced by abiotic stress and exogenous hormones, which indicated that SiSAUR genes may participated in complex physiological processes. CONCLUSIONS: Overall, these results will be valuable for further studies on the biological role of SAUR genes in foxtail development and response to stress conditions and may shed light on the improvement of the genetic breeding of foxtail millet.
PMID: 36639742
BMC Plant Biol , IF:4.215 , 2023 Jan , V23 (1) : P20 doi: 10.1186/s12870-023-04039-8
The auxin signaling pathway contributes to phosphorus-mediated zinc homeostasis in maize.
College of Resources and Environmental Sciences; National Academy of Agriculture Green Development; Key Laboratory of Plant-Soil Interactions, Ministry of Education, China Agricultural University, Beijing, 100193, People's Republic of China.; National Engineering Laboratory for Crop Molecular Breeding, Institute of Crop Science, Chinese Academy of Agricultural Sciences, Beijing, 100081, China.; National Engineering Laboratory for Crop Molecular Breeding, Institute of Crop Science, Chinese Academy of Agricultural Sciences, Beijing, 100081, China. liwenxue@caas.cn.; College of Resources and Environmental Sciences; National Academy of Agriculture Green Development; Key Laboratory of Plant-Soil Interactions, Ministry of Education, China Agricultural University, Beijing, 100193, People's Republic of China. zcq0206@cau.edu.cn.
Although the interaction between P and Zn has long been recognized in plants, the physiological and molecular mechanisms underlying P and Zn interactions are poorly understood. We show here that P supply decreases the Zn concentration in maize shoots and roots. Compared to +P + Zn (addition of both P and Zn), +P-Zn reduced and -P-Zn increased the total length of 1 degrees lateral roots (LRs). Under +P + Zn, both P and Zn concentrations were lower in the sl1 mutant roots than in wild-type (WT) maize roots, and P accumulation did not reduce the Zn concentration in ll1 mutant roots. Transcriptome profiling showed that the auxin signaling pathway contributed to P-mediated Zn homeostasis in maize. Auxin production and distribution were altered by changes in P and Zn supply. Cytosolic Zn co-localized with auxin accumulation under +P + Zn. Exogenous application of 1-NAA and L-Kyn altered the P-mediated root system architecture (RSA) under Zn deficiency. -P-Zn repressed the expression of miR167. Overexpression of ZmMIR167b increased the lengths of 1 degrees LRs and the concentrations of P and Zn in maize. These results indicate that auxin-dependent RSA is important for P-mediated Zn homeostasis in maize.HighlightAuxin-dependent RSA is important for P-mediated Zn homeostasis in maize.
PMID: 36627574
BMC Plant Biol , IF:4.215 , 2023 Jan , V23 (1) : P11 doi: 10.1186/s12870-022-04012-x
Analysis of co-expression and gene regulatory networks associated with sterile lemma development in rice.
College of Agriculture, Fujian Agriculture and Forestry University, Fuzhou, 350002, China.; Rice Research Institute, Fujian Academy of Agricultural Sciences, Fuzhou, 350019, China.; Key Laboratory of Germplasm Innovation and Molecular Breeding of Hybrid Rice for South China, Ministry of Agriculture and Affairs P.R. China/Incubator of National Key Laboratory of Germplasm Innovation and Molecular Breeding between Fujian and Ministry of Sciences and Technology/Fuzhou Branch, National Rice Improvement Center of China/Fujian Engineering Laboratory of Crop Molecular Breeding/Fujian Key Laboratory of Rice Molecular Breeding, Fuzhou, 350003, China.; Rice Research Institute, Fujian Academy of Agricultural Sciences, Fuzhou, 350019, China. huaanxie@163.com.; Key Laboratory of Germplasm Innovation and Molecular Breeding of Hybrid Rice for South China, Ministry of Agriculture and Affairs P.R. China/Incubator of National Key Laboratory of Germplasm Innovation and Molecular Breeding between Fujian and Ministry of Sciences and Technology/Fuzhou Branch, National Rice Improvement Center of China/Fujian Engineering Laboratory of Crop Molecular Breeding/Fujian Key Laboratory of Rice Molecular Breeding, Fuzhou, 350003, China. huaanxie@163.com.; Rice Research Institute, Fujian Academy of Agricultural Sciences, Fuzhou, 350019, China. jianfzhang@163.com.; Key Laboratory of Germplasm Innovation and Molecular Breeding of Hybrid Rice for South China, Ministry of Agriculture and Affairs P.R. China/Incubator of National Key Laboratory of Germplasm Innovation and Molecular Breeding between Fujian and Ministry of Sciences and Technology/Fuzhou Branch, National Rice Improvement Center of China/Fujian Engineering Laboratory of Crop Molecular Breeding/Fujian Key Laboratory of Rice Molecular Breeding, Fuzhou, 350003, China. jianfzhang@163.com.
BACKGROUND: The sterile lemma is a unique organ of the rice (Oryza sativa L.) spikelet. However, the characteristics and origin of the rice sterile lemma have not been determined unequivocally, so it is important to elucidate the molecular mechanism of the development of the sterile lemma. RESULTS: In the paper, we outline the regulatory mechanism of sterile lemma development by LONG STERILE LEMMA1 (G1), which has been identified as the gene controlling sterile lemma development. Based on the comprehensive analyses of transcriptome dynamics during sterile lemma development with G1 alleles between wild-type (WT) and mutant (MT) in rice, we obtained co-expression data and regulatory networks related to sterile lemma development. Co-transfection assays of rice protoplasts confirmed that G1 affects the expression of various phytohormone-related genes by regulating a number of critical transcription factors, such as OsLBD37 and OSH1. The hormone levels in sterile lemmas from WT and MT of rice supports the hypotheses that lower auxin, lower gibberellin, and higher cytokinin concentrations are required to maintain a normal phenotype of sterile lemmas. CONCLUSION: The regulatory networks have considerable reference value, and some of the regulatory relationships exhibiting strong correlations are worthy of further study. Taken together, these work provided a detailed guide for further studies into the molecular mechanism of sterile lemma development.
PMID: 36604645
Anal Bioanal Chem , IF:4.142 , 2023 Mar , V415 (7) : P1385-1393 doi: 10.1007/s00216-023-04529-6
A 3D-printed analytical device seamlessly integrating sample treatment for electrochemical detection of IAA in Marchantia polymorpha.
School of Public Health, Nantong University, 9 Seyuan Rd., Nantong, 226019, Jiangsu, China.; National Key Laboratory of Plant Molecular Genetics, CAS Center for Excellence in Molecular Plant Sciences, Institute of Plant Physiology and Ecology, Chinese Academy of Sciences, 300 Fenglin Road, Shanghai, 200032, China. liuwu@cemps.ac.cn.; School of Public Health, Nantong University, 9 Seyuan Rd., Nantong, 226019, Jiangsu, China. hxl362349@ntu.edu.cn.; School of Public Health, Nantong University, 9 Seyuan Rd., Nantong, 226019, Jiangsu, China. ningbao@ntu.edu.cn.
Because of the pivotal point of Marchantia polymorpha (M. polymorpha) in plant evolution, its auxin (mainly indole-3-acetic acid, IAA) levels could provide useful evidence for the study of the evolution of IAA. However, M. polymorpha could not be easily pretreated for electrochemical detection because they are at the entry level of land plants. Herein, we designed a three-dimensional (3D)-printed analytical device for seamless integration of sample treatment and electrochemical detection. Specifically, the electrochemical cell could be used as a mortar in which a tiny plant sample could be ground with a 3D-printed pestle, followed by mixing with the buffer solution under vibration for electrochemical detection of IAA with a disposable working electrode at the bottom of the cell. Using our strategy, the limits of quantification could reach 0.05 mumol L(-1) after optimization of parameters. We were able to demonstrate that IAA in different tissues of wild-type and mutant M. polymorpha could be successfully differentiated after they were treated with the 3D-printed analytical device. The obtained results were comparable to the samples blended with zirconium beads while the differences of IAA levels in different tissues of M. polymorpha agreed well with previous reports. This study suggested the potential of sample treatment integrated with electrochemical detection for analysis of IAA using the 3D printing techniques and their possible applications in the research of plants and other fields.
PMID: 36705731
Planta , IF:4.116 , 2023 Feb , V257 (3) : P48 doi: 10.1007/s00425-023-04086-3
Insights on the stem elongation of spur-type bud sport mutant of 'Red Delicious' apple.
College of Horticulture, Gansu Agricultural University, Lanzhou, 730070, China.; College of Bioengineering and Biotechnology, Tianshui Normal University, Tianshui, 741000, China.; College of Horticulture, Gansu Agricultural University, Lanzhou, 730070, China. bhch@gsau.edu.cn.
The decreased capacity of auxin-, CTK-, and BR-mediated cell division and cell enlargement pathways, combined with the enhanced capacity of GA and ETH-, JA-, ABA-, SA-mediated stress-resistant pathways were presumed to be the crucial reasons for the formation of spur-type 'Red Delicious' mutants. Vallee Spur', which exhibit short internodes and compact tree shape, is the fourth generation of the spur-type bud sport mutant of 'Red Delicious'. However, the underlying molecular mechanism of these properties remains unclear. Here, comparative phenotypic, full-length transcriptome and phytohormone analyses were performed between 'Red Delicious' (NSP) and 'Vallee Spur' (SP). The new shoot internode length of NSP was > 1.53-fold higher than that of the SP mutant. Cytological analysis showed that the stem cells of the SP mutant were smaller and more tightly arranged relative to the NSP. By Iso-Seq, a total of 1426 differentially expressed genes (DEGs) were detected, including 808 upregulated and 618 downregulated genes in new shoot apex with 2 leaves of the SP mutant. Gene expressions involved in auxin, cytokinin (CTK), and brassinosteroid (BR) signal transduction were mostly downregulated in the SP mutant, whereas those involved in gibberellin (GA), ethylene (ETH), jasmonate (JA), ABA, and salicylic acid (SA) signal transduction were mostly upregulated. The overall thermogram analysis of hormone levels in the shoot apex carrying two leaves detected by LC-MS/MS absolute quantification showed that the levels of IAA-Asp, IAA, iP7G, OPDA, and 6-deoxyCS were significantly upregulated in the SP mutant, while the remaining 28 hormones were significantly downregulated. It is speculated that the decreased capacity of auxin, CTK, and BR-mediated cell division and cell enlargement pathways is crucial for the formation of the SP mutant. GA and stress-resistant pathways of ETH, JA, ABA, and SA also play vital roles in stem elongation. These results highlight the involvement of phytohormones in the formation of stem elongation occurring in 'Red Delicious' spur-type bud sport mutants and provide information for exploring its biological mechanism.
PMID: 36740622
Genes (Basel) , IF:4.096 , 2023 Jan , V14 (2) doi: 10.3390/genes14020278
PyuARF16/33 Are Involved in the Regulation of Lignin Synthesis and Rapid Growth in Populus yunnanensis.
Key Laboratory for Forest Genetic and Tree Improvement &Propagation in Universities of Yunnan Province, Southwest Forestry University, Kunming 650224, China.; Key Laboratory of State Forestry Administration on Biodiversity Conservation in Southwest China, Southwest Forestry University, Kunming 650224, China.; Yunnan Academy of Biodiversity, Southwest Forestry University, Kunming 650224, China.; Key Laboratory for Forest Resources Conservation and Use in the Southwest Mountains of China, Ministry of Education, Southwest Forestry University, Kunming 650224, China.
(1) Background: Lignin is a unique component of the secondary cell wall, which provides structural support for perennial woody plants. ARFs are the core factors of the auxin-signaling pathway, which plays an important role in promoting plant growth, but the specific relationship between auxin response factors (ARFs) and lignin has not been fully elucidated with regard to rapid plant growth in forest trees. (2) Objectives: This study aimed to investigate the relationship between ARFs and lignin with regard to rapid plant growth in forest trees. (3) Methods: We used bioinformatics analysis to investigate the PyuARF family, find genes homologous to ARF6 and ARF8 in Populus yunnanensis, and explore the changes in gene expression and lignin content under light treatment. (4) Results: We identified and characterized 35 PyuARFs based on chromosome-level genome data from P. yunnanensis. In total, we identified 92 ARF genes in P. yunnanensis, Arabidopsis thaliana, and Populus trichocarpa, which were subsequently divided into three subgroups based on phylogenetic analysis and classified the conserved exon-intron structures and motif compositions of the ARFs into the same subgroups. Collinearity analysis suggested that segmental duplication and whole-genome duplication events were majorly responsible for the expansion of the PyuARF family, and the analysis of Ka/Ks indicated that the majority of the duplicated PyuARFs underwent purifying selection. The analysis of cis-acting elements showed that PyuARFs were sensitive to light, plant hormones, and stress. We analyzed the tissue-specific transcription profiles of PyuARFs with transcriptional activation function and the transcription profiles of PyuARFs with high expression under light in the stem. We also measured the lignin content under light treatment. The data showed that the lignin content was lower, and the gene transcription profiles were more limited under red light than under white light on days 1, 7, and 14 of the light treatments. The results suggest that PyuARF16/33 may be involved in the regulation of lignin synthesis, thereby promoting the rapid growth of P. yunnanensis. (5) Conclusions: Collectively, this study firstly reports that PyuARF16/33 may be involved in the regulation of lignin synthesis and in promoting the rapid growth in P. yunnanensis.
PMID: 36833205
Genes (Basel) , IF:4.096 , 2023 Jan , V14 (1) doi: 10.3390/genes14010181
A Genome-Wide View of the Transcriptome Dynamics of Fresh-Cut Potato Tubers.
Provincial Key Laboratory of Crops Genetic Improvement, Research Institute of Crops, Guangdong Academy of Agricultural Sciences, Guangzhou 510640, China.; Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Beijing 100081, China.; Agricultural Genomics Institute at Shenzhen, Chinese Academy of Agricultural Sciences, Shenzhen 518000, China.
Fresh fruits and vegetable products are easily perishable during postharvest handling due to enzymatic browning reactions. This phenomenon has contributed to a significant loss of food. To reveal the physiological changes in fresh-cut potato tubers at the molecular level, a transcriptome analysis of potato tubers after cutting was carried out. A total of 10,872, 10,449, and 11,880 differentially expressed genes (DEGs) were identified at 4 h, 12 h and 24 h after cutting, respectively. More than 87.5% of these DEGs were classified into the categories of biological process (BP) and molecular function (MF) based on Gene Ontology (GO) analysis. There was a difference in the response to cutting at different stages after the cutting of potato tubers. The genes related to the phenol and fatty biosynthesis pathways, which are responsible for enzymatic browning and wound healing in potato tubers, were significantly enriched at 0-24 h after cutting. Most genes related to the enzymatic browning of potato tubers were up-regulated in response to cut-wounding. Plant hormone biosynthesis, signal molecular biosynthesis and transduction-related genes, such as gibberelin (GA), cytokinin (CK), ethylene (ET), auxin (IAA), jasmonic acid (JA), salicylic (SA), and Respiratory burst oxidase (Rboh) significantly changed at the early stage after cutting. In addition, the transcription factors involved in the wound response were the most abundant at the early stage after cutting. The transcription factor with the greatest response to injury was MYB, followed by AP2-EREBP, C3H and WRKY. This study revealed the physiological changes at the molecular level of fresh-cut potato tubers after cutting. This information is needed for developing a better approach to enhancing the postharvest shelf life of fresh processed potato and the breeding of potato plants that are resistant to enzymatic browning.
PMID: 36672922
Plant Mol Biol , IF:4.076 , 2023 Feb , V111 (3) : P233-248 doi: 10.1007/s11103-022-01318-0
High temporal-resolution transcriptome landscapes of maize embryo sac and ovule during early seed development.
State Key Laboratory of Plant Physiology and Biochemistry, China Agricultural University, Beijing, People's Republic of China.; Department of Plant Genetics and Breeding, National Maize Improvement Center, China Agricultural University, Beijing, People's Republic of China.; CAS Center for Excellence in Molecular Plant Sciences, Chinese Academy of Sciences, Shanghai, People's Republic of China.; Engineering Research Center of Plant Growth Regulator, Ministry of Education & College of Agronomy and Biotechnology, China Agricultural University, Beijing, People's Republic of China.; Center for Crop Functional Genomics and Molecular Breeding, China Agricultural University, Beijing, People's Republic of China.; State Key Laboratory of Plant Physiology and Biochemistry, China Agricultural University, Beijing, People's Republic of China. jianchen@cau.edu.cn.; Department of Plant Genetics and Breeding, National Maize Improvement Center, China Agricultural University, Beijing, People's Republic of China. jianchen@cau.edu.cn.; Center for Crop Functional Genomics and Molecular Breeding, China Agricultural University, Beijing, People's Republic of China. jianchen@cau.edu.cn.
Here we provided a high temporal-resolution transcriptome atlas of maize embryo sac and ovule to reveal the gene activity dynamic during early seed development. The early maize (Zea mays) seed development is initiated from double fertilization in the embryo sac and needs to undergo a highly dynamic and complex development process to form the differentiated embryo and endosperm. Despite the importance of maize seed for food, feed, and biofuel, many regulators responsible for controlling its early development are not known yet. Here, we reported a high temporal-resolution transcriptome atlas of embryo sac and ovule based on 44 time point samples collected within the first four days of seed development. A total of 25,187 genes including 1598 transcription factors (TFs) involved in early seed development were detected. Global comparisons of the expressions of these genes revealed five distinct development stages of early seed, which are mainly related to double fertilization, asymmetric cell division of the zygote, as well as coenocyte formation, cellularization and differentiation in endosperm. We identified 3327 seed-specific genes, which more than one thousand seed-specific genes with main expressions during early seed development were newly identified here, including 859 and 186 genes predominantly expressed in the embryo sac and ovule, respectively. Combined with the published transcriptome data of seed, we uncovered the dominant auxin biosynthesis, transport and signaling related genes at different development stages and subregions of seed. These results are helpful for understanding the genetic control of early seed development.
PMID: 36508138
Plant Mol Biol , IF:4.076 , 2023 Jan , V111 (1-2) : P21-36 doi: 10.1007/s11103-022-01308-2
The involvement of AtMKK1 and AtMKK3 in plant-deleterious microbial volatile compounds-induced defense responses.
Graduate Program in Translational Agricultural Sciences, National Cheng Kung University and Academia Sinica, Tainan, Taiwan.; Institute of Tropical Plant Sciences and Microbiology, National Cheng Kung University, Tainan, Taiwan.; Department of Life Sciences, National Cheng Kung University, Tainan, Taiwan.; Department of Plant Systems Physiology, Radboud University, Nijmegen, The Netherlands.; Kaohsiung District Agricultural Research and Extension Station, Pingtung, Taiwan.; Graduate Program in Translational Agricultural Sciences, National Cheng Kung University and Academia Sinica, Tainan, Taiwan. haojen@mail.ncku.edu.tw.; Institute of Tropical Plant Sciences and Microbiology, National Cheng Kung University, Tainan, Taiwan. haojen@mail.ncku.edu.tw.; Department of Life Sciences, National Cheng Kung University, Tainan, Taiwan. haojen@mail.ncku.edu.tw.
Plant-deleterious microbial volatiles activate the transactivation of hypoxia, MAMPs and wound responsive genes in Arabidopsis thaliana. AtMKK1 and AtMKK3 are involved in the plant-deleterious microbial volatiles-induced defense responses. Microbial volatile compounds (mVCs) are a collection of volatile metabolites from microorganisms with biological effects on all living organisms. mVCs function as gaseous modulators of plant growth and plant health. In this study, the defense events induced by plant-deleterious mVCs were investigated. Enterobacter aerogenes VCs lead to growth inhibition and immune responses in Arabidopsis thaliana. E. aerogenes VCs negatively regulate auxin response and transport gene expression in the root tip, as evidenced by decreased expression of DR5::GFP, PIN3::PIN3-GFP and PIN4::PIN4-GFP. Data from transcriptional analysis suggests that E. aerogenes VCs trigger hypoxia response, innate immune responses and metabolic processes. In addition, the transcript levels of the genes involved in the synthetic pathways of antimicrobial metabolites camalexin and coumarin are increased after the E. aerogenes VCs exposure. Moreover, we demonstrate that MKK1 serves as a regulator of camalexin biosynthesis gene expression in response to E. aerogenes VCs, while MKK3 is the regulator of coumarin biosynthesis gene expression. Additionally, MKK1 and MKK3 mediate the E. aerogenes VCs-induced callose deposition. Collectively, these studies provide molecular insights into immune responses by plant-deleterious mVCs.
PMID: 36109466
Phytochemistry , IF:4.072 , 2023 Feb , V206 : P113531 doi: 10.1016/j.phytochem.2022.113531
Labdane diterpenoids from the heartwood of Leucosceptrum canum that impact on root growth and seed germination of Arabidopsis thaliana.
State Key Laboratory of Southwestern Chinese Medicine Resources, and Innovative Institute of Chinese Medicine and Pharmacy, Chengdu University of Traditional Chinese Medicine, Chengdu, 611137, PR China.; State Key Laboratory of Phytochemistry and Plant Resources in West China, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, 650201, PR China.; State Key Laboratory of Southwestern Chinese Medicine Resources, and Innovative Institute of Chinese Medicine and Pharmacy, Chengdu University of Traditional Chinese Medicine, Chengdu, 611137, PR China; State Key Laboratory of Phytochemistry and Plant Resources in West China, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, 650201, PR China. Electronic address: shli@cdutcm.edu.cn.
Eleven undescribed diterpenoids possessing labdane, 3,18-cyclo-labdane, 19 (4 --> 3)-labdane and 12-nor-labdane skeletons, named leucolactones A-K, were isolated from the heartwood of a large woody Lamiaceae plant, Leucosceptrum canum. Their structures were determined by NMR, MS, and in the case of leucolactones A by single crystal X-ray diffraction analysis. Plausible biosynthetic pathway of leucolactones were proposed. Leucolactones showed significant inhibitory effects against seed germination and root elongation of Arabidopsis thaliana in the Petri dish bioassay. Among them, the diastereomeric leucolactones G and H were the most potent, with EC(50) values for root elongation of 6.53 +/- 1.35 and 9.75 +/- 1.25 muM, respectively. The preliminary structure-activity relationship of leucolactones was discussed. The increase of auxin reporter activity in A. thaliana DR5::GUS roots by leucolactone H was observed, indicating that leucolactones altered auxin accumulation and distribution. These findings suggested that leucolactones might be involved in regulation of plant growth and development through altering auxin accumulation and distribution, presumably contributing to the heartwood formation in L. canum.
PMID: 36464100
BMC Genomics , IF:3.969 , 2023 Jan , V24 (1) : P41 doi: 10.1186/s12864-022-09098-z
Global transcriptome profiling reveals differential regulatory, metabolic and hormonal networks during somatic embryogenesis in Coffea arabica.
Nestle Research - Plant Science Research Unit, Tours, France. rayan.awada@cirad.fr.; UMR DIADE, CIRAD, Montpellier, France. rayan.awada@cirad.fr.; UMR DIADE, Universite de Montpellier, CIRAD, Montpellier, IRD, France. rayan.awada@cirad.fr.; Nestle Research - Plant Science Research Unit, Tours, France.; Nestle Research, Societe Des Produits Nestle SA, Lausanne, Switzerland.; Sophia Genetics, Geneve, Switzerland.; UMR DIADE, Universite de Montpellier, CIRAD, Montpellier, IRD, France.; UMR DIADE, IRD, Montpellier, France.; UMR DIADE, CIRAD, Montpellier, France.; Max Planck Institute for Molecular Plant Physiology, Golm, Germany.; School of BioSciences, The University of Melbourne, Parkville, VIC, Australia.
BACKGROUND: Somatic embryogenesis (SE) is one of the most promising processes for large-scale dissemination of elite varieties. However, for many plant species, optimizing SE protocols still relies on a trial and error approach. We report the first global scale transcriptome profiling performed at all developmental stages of SE in coffee to unravel the mechanisms that regulate cell fate and totipotency. RESULTS: RNA-seq of 48 samples (12 developmental stages x 4 biological replicates) generated 90 million high quality reads per sample, approximately 74% of which were uniquely mapped to the Arabica genome. First, the statistical analysis of transcript data clearly grouped SE developmental stages into seven important phases (Leaf, Dedifferentiation, Primary callus, Embryogenic callus, Embryogenic cell clusters, Redifferentiation and Embryo) enabling the identification of six key developmental phase switches, which are strategic for the overall biological efficiency of embryo regeneration. Differential gene expression and functional analysis showed that genes encoding transcription factors, stress-related genes, metabolism-related genes and hormone signaling-related genes were significantly enriched. Second, the standard environmental drivers used to control SE, i.e. light, growth regulators and cell density, were clearly perceived at the molecular level at different developmental stages. Third, expression profiles of auxin-related genes, transcription factor-related genes and secondary metabolism-related genes were analyzed during SE. Gene co-expression networks were also inferred. Auxin-related genes were upregulated during dedifferentiation and redifferentiation while transcription factor-related genes were switched on from the embryogenic callus and onward. Secondary metabolism-related genes were switched off during dedifferentiation and switched back on at the onset of redifferentiation. Secondary metabolites and endogenous IAA content were tightly linked with their respective gene expression. Lastly, comparing Arabica embryogenic and non-embryogenic cell transcriptomes enabled the identification of biological processes involved in the acquisition of embryogenic capacity. CONCLUSIONS: The present analysis showed that transcript fingerprints are discriminating signatures of cell fate and are under the direct influence of environmental drivers. A total of 23 molecular candidates were successfully identified overall the 12 developmental stages and can be tested in many plant species to optimize SE protocols in a rational way.
PMID: 36694132
Plants (Basel) , IF:3.935 , 2023 Feb , V12 (4) doi: 10.3390/plants12040944
Effects of Exogenous Auxin on Mesocotyl Elongation of Sorghum.
College of Agronomy, Shenyang Agriculture University, Shenyang 110866, China.; Jinzhou Academy of Agricultural Sciences, Jinzhou 121006, China.
The length of sorghum mesocotyl plays a vital role in seed emergence from the soil, which is the foundation of healthy growth. In this study, we aimed to understand how exogenous auxin (IAA) promoted mesocotyl elongation of sorghum and its physiology mechanism. The results presented that exogenous IAA significantly promoted mesocotyl elongation in MS24B (short mesocotyl inbred line) by increasing the cell length, while with extra exogenous NPA (IAA inhibitor) application, the mesocotyl length presented a significant short phenotype. In Z210 (long mesocotyl inbred line), exogenous IAA had a slight effect on mesocotyl length elongation, while the NPA treatment decreased the mesocotyl length considerably. In MS24B, IAA treatment increased the activity of amylase to degrade starch to soluble sugar, and the activity of hexokinase was improved to consume the increased soluble sugar to offer more energy. The energy will help to increase the activity of PM H(+)-ATPase and the expression of expansin-related genes, which ultimately will promote the acidification of the plasma membrane in MS24B for cell elongation. Overall, the exogenous IAA functioned on the activation of energy metabolism, which in turn, inducted the acidification of the plasma membrane for mesocotyl elongation.
PMID: 36840291
Plants (Basel) , IF:3.935 , 2023 Feb , V12 (4) doi: 10.3390/plants12040843
Brown Seaweed Extract (BSE) Application Influences Auxin- and ABA-Related Gene Expression, Root Development, and Sugar Yield in Beta vulgaris L.
Department of Agronomy, Food, Natural Resources, Animals and Environment (DAFNAE), Campus of Agripolis, University of Padova, Viale dell'Universita 16, 35020 Legnaro, Italy.; Crop Production and Biostimulation Laboratory, Interfacultary School of Bioengineers, Universite Libre de Bruxelles, Campus Plaine CP 245, Bd du Triomphe, 1050 Brussels, Belgium.; Dipartimento di Agricoltura Alimentazione e Ambiente (Di3A), Universita di Catania, Via S. Sofia 100, 95123 Catania, Italy.; Sofbey SA, Cso S. Gottardo 34, 6830 Chiasso, Switzerland.; CO.PRO.B-Cooperativa Produttori Bieticoli, Via Mora 56, 40061 Minerbio, Italy.
The molecular and phenotypic effects of a brown seaweed extract (BSE) were assessed in sugar beet (Beta vulgaris L.). Transcript levels of BSE-treated and untreated plants were studied by RNA-seq and validated by quantitative real-time PCR analysis (RT-qPCR). Root morphology, sugar yield, and processing quality traits were also analyzed to better elucidate the treatment effects. RNA-seq revealed 1019 differentially expressed genes (DEGs) between the BSE-treated and untreated plants. An adjusted p-value < 0.1 and an absolute value of log2 (fold change) greater than one was used as criteria to select the DEGs. Gene ontology (GO) identified hormone pathways as an enriched biological process. Six DEGs involved in auxin and ABA pathways were validated using RT-qPCR. The phenotypic characterization indicated that BSE treatment led to a significant increase (p < 0.05) in total root length and the length of fine roots of plants grown under hydroponics conditions. The sugar yield of plants grown under field conditions was higher (p < 0.05) in the treated field plots compared with the control treatment, without impacting the processing quality. Our study unveiled the relevant effects of BSE application in regulating auxin- and ABA-related gene expression and critical traits related to sugar beet development and yield.
PMID: 36840191
Plants (Basel) , IF:3.935 , 2023 Feb , V12 (4) doi: 10.3390/plants12040750
The ROP2 GTPase Participates in Nitric Oxide (NO)-Induced Root Shortening in Arabidopsis.
Institute of Plant Biology, Biological Research Centre, Eotvos Lorand Research Network, Temesvari Krt. 62, H-6726 Szeged, Hungary.; Department of Plant Biology, University of Szeged, Kozep Fasor 52, H-6726 Szeged, Hungary.; Laboratory of Proteomics Research, Biological Research Centre, Eotvos Lorand Research Network, Temesvari Krt. 62, H-6726 Szeged, Hungary.; Hungarian Centre of Excellence for Molecular Medicine, Single Cell Omics ACF, H-6728 Szeged, Hungary.; Institute of Biochemical Plant Pathology, Helmholtz Zentrum Munchen-German Research Center for Environmental Health, Ingolstadter Landstrasse 1, D-85764 Neuherberg, Germany.
Nitric oxide (NO) is a versatile signal molecule that mediates environmental and hormonal signals orchestrating plant development. NO may act via reversible S-nitrosation of proteins during which an NO moiety is added to a cysteine thiol to form an S-nitrosothiol. In plants, several proteins implicated in hormonal signaling have been reported to undergo S-nitrosation. Here, we report that the Arabidopsis ROP2 GTPase is a further potential target of NO-mediated regulation. The ROP2 GTPase was found to be required for the root shortening effect of NO. NO inhibits primary root growth by altering the abundance and distribution of the PIN1 auxin efflux carrier protein and lowering the accumulation of auxin in the root meristem. In rop2-1 insertion mutants, however, wild-type-like root size of the NO-treated roots were maintained in agreement with wild-type-like PIN1 abundance in the meristem. The ROP2 GTPase was shown to be S-nitrosated in vitro, suggesting that NO might directly regulate the GTPase. The potential mechanisms of NO-mediated ROP2 GTPase regulation and ROP2-mediated NO signaling in the primary root meristem are discussed.
PMID: 36840099
Plants (Basel) , IF:3.935 , 2023 Feb , V12 (3) doi: 10.3390/plants12030681
Effects of Co-Inoculating Saccharomyces spp. with Bradyrhizobium japonicum on Atmospheric Nitrogen Fixation in Soybeans (Glycine max (L.)).
School of Life Science and Engineering, Southwest University of Science and Technology, Mianyang 621010, China.; Department of Crop and Forest Sciences, University of Lleida, 25198 Lleida, Spain.; Joint Research Unit CTFC-AGROTECNIO, Universitat de Lleida, 25198 Lleida, Spain.; Fundamental Science on Nuclear Wastes and Environmental Safety Laboratory, Southwest University of Science and Technology, Mianyang 621010, China.; Center of Analysis and Testing, Southwest University of Science and Technology, Mianyang 621010, China.; School of Environment and Resource, Southwest University of Science and Technology, Mianyang 621010, China.; Key Laboratory of Solid Waste Treatment and Resource Recycle, Southwest University of Science and Technology, Mianyang 621010, China.
Crop production encounters challenges due to the dearth of nitrogen (N) and phosphorus (P), while excessive chemical fertilizer use causes environmental hazards. The use of N-fixing microbes and P-solubilizing microbes (PSMs) can be a sustainable strategy to overcome these problems. Here, we conducted a greenhouse pot experiment following a completely randomized blocked design to elucidate the influence of co-inoculating N-fixing bacteria (Bradyrhizobium japonicum) and PSMs (Saccharomyces cerevisiae and Saccharomyces exiguus) on atmospheric N(2)-fixation, growth, and yield. The results indicate a significant influence of interaction on Indole-3-acetic acid production, P solubilization, seedling germination, and growth. It was also found that atmospheric N(2)-fixation, nodule number per plant, nodule dry weight, straw, and root dry weight per plant at different growth stages were significantly increased under dual inoculation treatments relative to single inoculation or no inoculation treatment. Increased seed yield and N and P accumulation were also noticed under co-inoculation treatments. Soil available N was highest under sole bacterial inoculation and lowest under the control treatment, while soil available P was highest under co-inoculation treatments and lowest under the control treatment. We demonstrated that the co-inoculation of N-fixing bacteria and PSMs enhances P bioavailability and atmospheric N(2)-fixation in soybeans leading to improved soil fertility, raising crop yields, and promoting sustainable agriculture.
PMID: 36771765
Plants (Basel) , IF:3.935 , 2023 Feb , V12 (3) doi: 10.3390/plants12030658
Assessment of the Effect of Treating 'GiSelA 5' Softwood Cuttings with Biostimulants and Synthetic Auxin on Their Root Formation and Some of Their Physiological Parameters.
Department of Ornamental Plants, Dendrology and Pomology, Poznan University of Life Sciences, Dabrowskiego 159, 60-594 Poznan, Poland.
The 'GiSelA 5' rootstock is of high importance for growing sweet cherries because it significantly reduces the growth vigour of the trees and accelerates their fruiting. However, the method of its propagation using 'in vitro' cultures is expensive, prompting researchers to look for alternative methods of propagation. One of these is the root formation in shoot cuttings. The experiment presented in this paper compared the use of powdered synthetic auxins (Rhizopon AA, Ukorzeniacz AB) and their alcoholic solution (IAA, IBA), and the biostimulants Goteo and Bispeed as foliar sprays for root formation in softwood cuttings 'GiSelA 5' and measured some parameters of physiological processes. In addition, two different substrates of river sand with peat (1:2) and peat substrate with perlite (2:1) were used. Cuttings were obtained on two dates, in the first and third years in the month of June. Biostimulants increased the number of rooted cuttings (Goteo-16.1%, Bispeed-18.1%) without improving their growth and the intensity of most of the analyzed physiological processes compared to the control. Synthetic preparations also increased the percentage of rooted cuttings Rhizopon AA (24.4%), Ukorzeniacz AB (21.4%), auxin IBA (19.7%) and auxin IAA (14.7%), while simultaneously improving their growth and level of vital processes compared to the controls and biostimulants. The substrate consisting of peat with sand improved root formation by 6.2%, without significantly changing the growth parameters and vital functions of the cuttings. The earlier date of propagation increased the root formation percentage only by 4% and the number of roots by 14% of the 'GiSelA 5' rootstock cuttings.
PMID: 36771741
Plants (Basel) , IF:3.935 , 2023 Jan , V12 (3) doi: 10.3390/plants12030606
Recent Advances in the Bacterial Phytohormone Modulation of Plant Growth.
Departamento de Ingenieria Bioquimica y Ambiental, Tecnologico Nacional de Mexico/I.T. Celaya, Celaya 38110, Guanajuato, Mexico.; Genomic Diversity Laboratory, Institute of Biological and Chemical Research, Universidad Michoacana de San Nicolas de Hidalgo, Morelia 58030, Michoacan, Mexico.; Department of Biology, University of Waterloo, Waterloo, ON N2L 3G1, Canada.
Phytohormones are regulators of plant growth and development, which under different types of stress can play a fundamental role in a plant's adaptation and survival. Some of these phytohormones such as cytokinin, gibberellin, salicylic acid, auxin, and ethylene are also produced by plant growth-promoting bacteria (PGPB). In addition, numerous volatile organic compounds are released by PGPB and, like bacterial phytohormones, modulate plant physiology and genetics. In the present work we review the basic functions of these bacterial phytohormones during their interaction with different plant species. Moreover, we discuss the most recent advances of the beneficial effects on plant growth of the phytohormones produced by PGPB. Finally, we review some aspects of the cross-link between phytohormone production and other plant growth promotion (PGP) mechanisms. This work highlights the most recent advances in the essential functions performed by bacterial phytohormones and their potential application in agricultural production.
PMID: 36771689
Plants (Basel) , IF:3.935 , 2023 Jan , V12 (3) doi: 10.3390/plants12030524
Co-Inoculation of Endophytes Bacillus siamensis TUR07-02b and Priestia megaterium SMBH14-02 Promotes Growth in Rice with Low Doses of Nitrogen Fertilizer.
Laboratorio de Microbiologia Agricola, Departamento Academico Agrosilvopastoril, Facultad de Ciencias Agrarias, Universidad Nacional de San Martin, Tarapoto 22202, Peru.; Departamento Academico de Ciencias Basicas, Facultad de Ingenieria, Universidad Nacional de Barranca, Barranca 15169, Peru.
Multiple biotic and abiotic factors influence rice cultivation. These factors limit productivity and yield, as well as an irrational use of agrochemicals in rice cultivation. A sustainable alternative is using selected growth-promoting microorganisms to increase nutritional efficiency. In the present study, the direct mechanisms of growth promotion in two strains of Bacillus, three strains of Priestia, and two strains of Burkholderia endophytes of rice were characterized. Bacillus siamensis TUR07-02b and Priestia megaterium SMBH14-02 were selected to promote Oryza sativa var's growth. "Bellavista" was used at different doses (50, 75, and 100%) of mineral nitrogen (N) using a randomized block design by quintuplicate. Both strains, SMBH14-02 and TUR07-02b, presented outstanding promoter characteristics, including auxin production (123.17 and 335.65 mug mL(-1), respectively) and biological nitrogen fixation capacity. Similarly, B. siamensis TUR07-02b could solubilize phosphate-Ca (20.94 mug mL(-1)), cellulases, and pectinases. Under greenhouse conditions, co-inoculated plants receiving 75% of the total dose of mineral nitrogen showed increased agronomic parameters in relation to panicle length, grains per panicle, grain yield, and harvest index by 25.0, 30.7, 39.5, and 12.5%, respectively, compared to the 75% fertilized treatment without inoculation. The strains of B. siamensis TUR07-02b and P. megaterium SMBH14-02 are potential microbial resources in the formulation of new inoculants to reduce the use of nitrogenous fertilizers. Thus, agronomic validation of the inoculant consortium at the field level will be an essential step in providing an alternative for the sustainable management of rice cultivation and increased productivity of rice farmers in the San Martin region.
PMID: 36771609
Plants (Basel) , IF:3.935 , 2023 Jan , V12 (3) doi: 10.3390/plants12030517
Friends in Arms: Flavonoids and the Auxin/Cytokinin Balance in Terrestrialization.
Plant Physiology, Biochemistry, Molecular Biology Program, Department of Plant and Soil Sciences, University of Kentucky, Lexington, KY 40546, USA.
Land plants survive the challenges of new environments by evolving mechanisms that protect them from excess irradiation, nutrient deficiency, and temperature and water availability fluctuations. One such evolved mechanism is the regulation of the shoot/root growth ratio in response to water and nutrient availability by balancing the actions of the hormones auxin and cytokinin. Plant terrestrialization co-occurred with a dramatic expansion in secondary metabolism, particularly with the evolution and establishment of the flavonoid biosynthetic pathway. Flavonoid biosynthesis is responsive to a wide range of stresses, and the numerous synthesized flavonoid species offer two main evolutionary advantages to land plants. First, flavonoids are antioxidants and thus defend plants against those adverse conditions that lead to the overproduction of reactive oxygen species. Second, flavonoids aid in protecting plants against water and nutrient deficiency by modulating root development and establishing symbiotic relations with beneficial soil fungi and bacteria. Here, we review different aspects of the relationships between the auxin/cytokinin module and flavonoids. The current body of knowledge suggests that whereas both auxin and cytokinin regulate flavonoid biosynthesis, flavonoids act to fine-tune only auxin, which in turn regulates cytokinin action. This conclusion agrees with the established master regulatory function of auxin in controlling the shoot/root growth ratio.
PMID: 36771601
Plants (Basel) , IF:3.935 , 2023 Jan , V12 (3) doi: 10.3390/plants12030488
Micropropagation as a Tool for the Conservation of Autochthonous Sorbus Species of Czechia.
Silva Tarouca Research Institute for Landscape and Ornamental Gardening, Public Research Institute, Kvetnove namesti 391, 252 43 Pruhonice, Czech Republic.
Members of the genus Sorbus are the only endemic tree species that occur in Czechia. They are important components of endangered plant communities. Their natural regeneration is usually problematic because of their mode of reproduction and because they can survive in rare populations with small numbers of individuals. The aim of this study was to develop a successful micropropagation protocol for selected Sorbus species, of which two are endemic (S. gemella and S. omissa) and two are hybrid (S. x abscondita and S. x kitaibeliana). We found significant differences in shoot induction and rooting ability between the Sorbus species under study. With the exception of S. x abscondita, N(6)-benzyladenine had a significantly greater effect on shoot regeneration, both in terms of shoot number and total shoot length, than meta-topolin. Root induction was key to the successful micropropagation of the Sorbus species studied. Our results show that four Sorbus species can be successfully rooted under ex vitro conditions, without a rooting powder treatment in a steamed peat-perlite substrate. Auxin-untreated microcuttings of S. gemella, S. x kitaibeliana and S. omissa, but not S. x abscondita, rooted better than ones treated with indole-3-butyric acid. This is the first time a micropropagation protocol for S. omissa, S. x abscondita and S. x kitaibeliana has been published.
PMID: 36771573
Plants (Basel) , IF:3.935 , 2023 Jan , V12 (2) doi: 10.3390/plants12020413
New Paradigms in Brassinosteroids, Strigolactones, Sphingolipids, and Nitric Oxide Interaction in the Control of Lateral and Adventitious Root Formation.
Department of Environmental Biology, Sapienza University of Rome, 00185 Rome, Italy.; Department of Biosciences, University of Milan, 20133 Milan, Italy.
The root system is formed by the primary root (PR), which forms lateral roots (LRs) and, in some cases, adventitious roots (ARs), which in turn may produce their own LRs. The formation of ARs is also essential for vegetative propagation in planta and in vitro and for breeding programs. Root formation and branching is coordinated by a complex developmental network, which maximizes the plant's ability to cope with abiotic stress. Rooting is also a response caused in a cutting by wounding and disconnection from the donor plant. Brassinosteroids (BRs) are steroid molecules perceived at the cell surface. They act as plant-growth-regulators (PGRs) and modulate plant development to provide stress tolerance. BRs and auxins control the formation of LRs and ARs. The auxin/BR interaction involves other PGRs and compounds, such as nitric oxide (NO), strigolactones (SLs), and sphingolipids (SPLs). The roles of these interactions in root formation and plasticity are still to be discovered. SLs are carotenoid derived PGRs. SLs enhance/reduce LR/AR formation depending on species and culture conditions. These PGRs possibly crosstalk with BRs. SPLs form domains with sterols within cellular membranes. Both SLs and SPLs participate in plant development and stress responses. SPLs are determinant for auxin cell-trafficking, which is essential for the formation of LRs/ARs in planta and in in vitro systems. Although little is known about the transport, trafficking, and signaling of SPLs, they seem to interact with BRs and SLs in regulating root-system growth. Here, we review the literature on BRs as modulators of LR and AR formation, as well as their crosstalk with SLs and SPLs through NO signaling. Knowledge on the control of rooting by these non-classical PGRs can help in improving crop productivity and enhancing AR-response from cuttings.
PMID: 36679126
Plants (Basel) , IF:3.935 , 2023 Jan , V12 (2) doi: 10.3390/plants12020409
Auxin Transporter OsPIN1b, a Novel Regulator of Leaf Inclination in Rice (Oryza sativa L.).
Key Laboratory of Herbage & Endemic Crop Biology of Ministry of Education, Inner Mongolia Key Laboratory of Herbage & Endemic Crop Biotechnology, School of Life Sciences, Inner Mongolia University, Hohhot 010030, China.; State Key Laboratory of Plant Physiology and Biochemistry, College of Life Sciences, Zhejiang University, Hangzhou 310058, China.; State Key Laboratory of Rice Biology, China National Rice Research Institute, Chinese Academy of Agricultural Sciences, Hangzhou 310006, China.; College of Life Science and Technology, Inner Mongolia Normal University, Hohhot 010022, China.
Leaf inclination is one of the most important components of the ideal architecture, which effects yield gain. Leaf inclination was shown that is mainly regulated by brassinosteroid (BR) and auxin signaling. Here, we reveal a novel regulator of leaf inclination, auxin transporter OsPIN1b. Two CRISPR-Cas9 homozygous mutants, ospin1b-1 and ospin1b-2, with smaller leaf inclination compared to the wild-type, Nipponbare (WT/NIP), while overexpression lines, OE-OsPIN1b-1 and OE-OsPIN1b-2 have opposite phenotype. Further cell biological observation showed that in the adaxial region, OE-OsPIN1b-1 has significant bulge compared to WT/NIP and ospin1b-1, indicating that the increase in the adaxial cell division results in the enlarging of the leaf inclination in OE-OsPIN1b-1. The OsPIN1b was localized on the plasma membrane, and the free IAA contents in the lamina joint of ospin1b mutants were significantly increased while they were decreased in OE-OsPIN1b lines, suggesting that OsPIN1b might action an auxin transporter such as AtPIN1 to alter IAA content and leaf inclination. Furthermore, the OsPIN1b expression was induced by exogenous epibrassinolide (24-eBL) and IAA, and ospin1b mutants are insensitive to BR or IAA treatment, indicating that the effecting leaf inclination is regulated by OsPIN1b. This study contributes a new gene resource for molecular design breeding of rice architecture.
PMID: 36679122
Plants (Basel) , IF:3.935 , 2023 Jan , V12 (2) doi: 10.3390/plants12020378
SlIAA9 Mutation Maintains Photosynthetic Capabilities under Heat-Stress Conditions.
Master Program of Agronomy, Faculty of Agriculture, Universitas Padjadjaran, Sumedang 45363, Indonesia.; Under Graduate Program of Agrotechnology, Faculty of Agriculture, Universitas Padjadjaran, Sumedang 45363, Indonesia.; Department of Agronomy, Faculty of Agriculture, Universitas Padjadjaran, Sumedang 45363, Indonesia.; Department of Biology, Institut Teknologi Sepuluh Nopember, Surabaya 60111, Indonesia.; Department of Plant Protection, Faculty of Agriculture, Universitas Gadjah Mada, Yogyakarta 55281, Indonesia.; Department of Agronomy and Horticulture, Faculty of Agriculture, IPB University, Bogor 16680, Indonesia.; Faculty of Life and Environmental Sciences, University of Tsukuba, Tsukuba 305-8577, Japan.; Tsukuba Plant Innovation Research Center, University of Tsukuba, Tsukuba 305-8577, Japan.
Tomato is one of the most widely consumed horticultural products. However, tomato is very sensitive to changes in temperature. Daily average temperatures above 32 degrees C severely reduced tomato plant growth, development, and productivity. Therefore, climate change-induced global warming is a major threat to future tomato production. Good photosynthetic capability under heat stress conditions is known to be a major sign of heat tolerance. Tomato INDOLE-ACETIC-ACID (SlIAA9) is a transcriptional repressor in auxin signaling. SlIAA9 mutation caused heightened endogenous auxin response and biosynthesis within plant tissues. In this study, we studied the photosynthetic capability of iaa9-3 and iaa9-5 mutants under heat-stress conditions. We discovered that both iaa9-3 and iaa9-5 could maintain their photosynthetic capability after 14 days of heat treatment (>40 degrees C), differing from Wild Type-Micro-Tom (WT-MT) tomato. Both iaa9 mutants had higher net photosynthetic rate, stomatal conductance, leaf total chlorophyll, leaf carotenoids, Fv/Fm value, and lower leaf MDA than WT-MT. These results suggested that the SlIAA9 mutation benefits plant adaptation to heat stress.
PMID: 36679090
Plants (Basel) , IF:3.935 , 2023 Jan , V12 (2) doi: 10.3390/plants12020371
The Arabidopsis LHT1 Amino Acid Transporter Contributes to Pseudomonas simiae-Mediated Plant Growth Promotion by Modulating Bacterial Metabolism in the Rhizosphere.
Department of Biology, University of Virginia, Charlottesville, VA 22904, USA.; Department of Molecular Biology & Biotechnology, School of Biological Sciences, College of Agriculture & Natural Sciences, University of Cape Coast, UC, Cape Coast P.O. Box 5007, Ghana.
The root microbiome structure ensures optimal plant host health and fitness, and it is, at least in part, defined by the plant genotype. It is well documented that root-secreted amino acids promote microbial chemotaxis and growth in the rhizosphere. However, whether the plant-mediated re-uptake of amino acids contributes to maintaining optimal levels of amino acids in the root exudates, and, in turn, microbial growth and metabolism, remains to be established. Here, we show that Lysine-Histidine Transporter-1 (LHT1), an amino acid inward transporter expressed in Arabidopsis thaliana roots, limits the growth of the plant-growth-promoting bacteria Pseudomonas simiae WCS417r (Ps WCS417r). The amino acid profiling of the lht1 mutant root exudates showed increased levels of glutamine, among other amino acids. Interestingly, lht1 exudates or Gln-supplemented wild-type exudates enhance Ps WCS417r growth. However, despite promoting bacterial growth and robust root colonization, lht1 exudates and Gln-supplemented wild-type exudates inhibited plant growth in a Ps WCS417r-dependent manner. The transcriptional analysis of defense and growth marker genes revealed that plant growth inhibition was not linked to the elicitation of plant defense but likely to the impact of Ps WCS417r amino acids metabolism on auxin signaling. These data suggest that an excess of amino acids in the rhizosphere impacts Ps WCS417r metabolism, which, in turn, inhibits plant growth. Together, these results show that LHT1 regulates the amino-acid-mediated interaction between plants and Ps WCS417r and suggest a complex relationship between root-exuded amino acids, root colonization by beneficial bacteria, bacterial metabolism, and plant growth promotion.
PMID: 36679084
Plants (Basel) , IF:3.935 , 2023 Jan , V12 (2) doi: 10.3390/plants12020354
Characterization and Transcriptome Analysis of Maize Small-Kernel Mutant smk7a in Different Development Stages.
College of Agronomy, Gansu Agricultural University, Lanzhou 730070, China.; National Engineering Research Center of Crop Molecular Breeding, Institute of Crop Sciences, Chinese Academy of Agricultural Sciences, Beijing 100081, China.; Gansu Provincial Key Laboratory of Aridland Crop Science, Gansu Agricultural University, Lanzhou 730070, China.
The kernel serves as a storage organ for various nutrients and determines the yield and quality of maize. Understanding the mechanisms regulating kernel development is important for maize production. In this study, a small-kernel mutant smk7a of maize was characterized. Cytological observation suggested that the development of the endosperm and embryo was arrested in smk7a in the early development stage. Biochemical tests revealed that the starch, zein protein, and indole-3-acetic acid (IAA) contents were significantly lower in smk7a compared with wild-type (WT). Consistent with the defective development phenotype, transcriptome analysis of the kernels 12 and 20 days after pollination (DAP) revealed that the starch, zein, and auxin biosynthesis-related genes were dramatically downregulated in smk7a. Genetic mapping indicated that the mutant was controlled by a recessive gene located on chromosome 2. Our results suggest that disrupted nutrition accumulation and auxin synthesis cause the defective endosperm and embryo development of smk7a.
PMID: 36679067
Plants (Basel) , IF:3.935 , 2023 Jan , V12 (2) doi: 10.3390/plants12020330
ATANN3 Is Involved in Extracellular ATP-Regulated Auxin Distribution in Arabidopsis thaliana Seedlings.
Ministry of Education Key Laboratory of Molecular and Cellular Biology, College of Life Sciences, Hebei Normal University, Shijiazhuang 050024, China.
Extracellular ATP (eATP) plays multiple roles in plant growth and development, and stress responses. It has been revealed that eATP suppresses growth and alters the growth orientation of the root and hypocotyl of Arabidopsis thaliana by affecting auxin transport and localization in these organs. However, the mechanism of the eATP-stimulated auxin distribution remains elusive. Annexins are involved in multiple aspects of plant cellular metabolism, while their role in response to apoplastic signals remains unclear. Here, by using the loss-of-function mutations, we investigated the role of AtANN3 in the eATP-regulated root and hypocotyl growth. Firstly, the inhibitory effects of eATP on root and hypocotyl elongation were weakened or impaired in the AtANN3 null mutants (atann3-1 and atann3-2). Meanwhile, the distribution of DR5-GUS and DR5-GFP indicated that the eATP-induced asymmetric distribution of auxin in the root tips or hypocotyl cells occurred in wild-type control plants, while in atann3-1 mutant seedlings, it was not observed. Further, the eATP-induced asymmetric distribution of PIN2-GFP in root-tip cells or that of PIN3-GFP in hypocotyl cells was reduced in atann3-1 seedlings. Finally, the eATP-induced asymmetric distribution of cytoplasmic vesicles in root-tip cells was impaired in atann3-1 seedlings. Based on these results, we suggest that AtANN3 may be involved in eATP-regulated seedling growth by regulating the distribution of auxin and auxin transporters in vegetative organs.
PMID: 36679043
Plants (Basel) , IF:3.935 , 2023 Jan , V12 (2) doi: 10.3390/plants12020289
IBA Delivery Technique and Media Salts Affected In Vitro Rooting and Acclimatization of Eight Prunus Genotypes.
Department of Plant and Environmental Sciences, Clemson University, Clemson, SC 29634, USA.; Department of Mathematics, Clemson University, Clemson, SC 29634, USA.
Difficult-to-root plants often perform poorly during acclimatization and in vitro rooting can increase the survival and quality of plants. The influence of auxin application and mineral nutrition on in vitro rooting and subsequent effects on plant quality in eight Prunus genotypes were investigated. Microshoots were rooted in vitro on Murashige and Skoog (MS), (1/2) MS, Driver and Kuniyuki (DKW), or New Prunus Medium (NPM) media formulations in combination with 15 microM indole-3-butyric acid (IBA), 4-day 15 microM IBA pulse, 1 mM 30 s quick-dip, or IBA-free treatments. Shoots were observed pre- and post-acclimatization to determine rooting methods to maximize quality and minimize labor. A genotype-specific response to auxin application was observed with seven of eight genotypes achieving 100% survival when paired with the recommended IBA treatment. Peaches performed best when treated with 4-day IBA pulse or 30 s quick-dip. Rooting of P. cerasifera, it's hybrid to P. persica, and P. munsoniana all benefitted from IBA application. Shoots rooted with 15 microM IBA were smaller and lower quality in most genotypes. DKW maximized size and quality in six genotypes. Better shoots and larger root systems during in vitro rooting produced better plants in the greenhouse with no detrimental effect of callus growth. Rooting techniques to maximize plant quality while reducing labor are specified.
PMID: 36679002
Plants (Basel) , IF:3.935 , 2023 Jan , V12 (2) doi: 10.3390/plants12020266
Occurrence, Function, and Biosynthesis of the Natural Auxin Phenylacetic Acid (PAA) in Plants.
Plant Molecular and Cellular Biology, University of Florida, Gainesville, FL 32611, USA.; Horticultural Sciences Department, University of Florida, Gainesville, FL 32611, USA.; Genetic Institute, University of Florida, Gainesville, FL 32611, USA.
Auxins are a class of plant hormones playing crucial roles in a plant's growth, development, and stress responses. Phenylacetic acid (PAA) is a phenylalanine-derived natural auxin found widely in plants. Although the auxin activity of PAA in plants was identified several decades ago, PAA homeostasis and its function remain poorly understood, whereas indole-3-acetic acid (IAA), the most potent auxin, has been used for most auxin studies. Recent studies have revealed unique features of PAA distinctive from IAA, and the enzymes and intermediates of the PAA biosynthesis pathway have been identified. Here, we summarize the occurrence and function of PAA in plants and highlight the recent progress made in PAA homeostasis, emphasizing PAA biosynthesis and crosstalk between IAA and PAA homeostasis.
PMID: 36678978
Plants (Basel) , IF:3.935 , 2023 Jan , V12 (2) doi: 10.3390/plants12020227
Transcriptomic Insights into Functions of LkABCG36 and LkABCG40 in Nicotiana tabacum.
College of Biological Sciences and Biotechnology, Beijing Forestry University, Beijing 100083, China.; State Key Laboratory of Tree Genetics and Breeding, College of Biological Sciences and Technology, Beijing Forestry University, Beijing 100083, China.; National Engineering Laboratory for Tree Breeding, The Tree and Ornamental Plant Breeding and Biotechnology Laboratory of Chinese Forestry Administration, Beijing 100083, China.
ATP-binding cassette transporters (ABC transporters) play crucial physiological roles in plants, such as being involved in the growth and development of organs, nutrient acquisition, response to biotic and abiotic stress, disease resistance, and the interaction of the plant with its environment. The ABCG subfamily of proteins are involved in the process of plant vegetative organ development. In contrast, the functions of the ABCG36 and ABCG40 transporters have received considerably less attention. Here, we investigated changes in the transcriptomic data of the stem tissue of transgenic tobacco (Nicotiana tabacum) with LkABCG36 and LkABCG40 (Larix kaempferi) overexpression, and compared them with those of the wild type (WT). Compared with the WT, we identified 1120 and 318 differentially expressed genes (DEGs) in the LkABCG36 and LkABCG40 groups, respectively. We then annotated the function of the DEGs against the Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) databases. The results showed enrichment in cell wall biogenesis and hormone signal transduction functional classes in transgenic LkABCG36 tobacco. In transgenic LkABCG40 tobacco, the enrichment was involved in metabolic and biosynthetic processes, mainly those related to environmental adaptation. In addition, among these DEGs, many auxin-related genes were significantly upregulated in the LkABCG36 group, and we found key genes involved in environmental adaptation in the LkABCG40 group, including an encoding resistance protein and a WRKY transcription factor. These results suggest that LkABCG36 and LkABCG40 play important roles in plant development and environmental adaptation. LkABCG36 may promote plant organ growth and development by increasing auxin transport, whereas LkABCG40 may inhibit the expression of WRKY to improve the resistance of transgenic tobacco. Our results are beneficial to researchers pursuing further study of the functions of ABCG36 and ABCG40.
PMID: 36678941
Plants (Basel) , IF:3.935 , 2023 Jan , V12 (2) doi: 10.3390/plants12020225
Optimized Recovery of Cryostored Dormant Buds of Mulberry Germplasm.
Seed Science and Technology, ICAR-Indian Agricultural Research Institute, Pusa Campus, New Delhi 110012, India.; Tissue Culture and Cryopreservation Unit, ICAR-National Bureau of Plant Genetic Resources, Pusa Campus, New Delhi 110012, India.; Central Sericultural Germplasm Resources Center, Hosur 635109, India.
A two-step freezing cryoprotocol preceded by desiccation to 15 to 25% moisture content was developed and successfully applied to winter dormant buds of mulberry (different Morus spp.) of a core set comprising 238 accessions studies in our laboratory. The survival and recovery percentage of diverse accessions cryobanked for various periods were tested under in vitro conditions, and several factors were analyzed to determine their role in optimizing the recovery of low-viability accessions. The effect of rates of freezing and thawing (both fast and slow), were tested and recovery compared. Recovery conditions such as dark incubation and rehydration in sterile moist moss grass for different durations after cryopreservation led to a higher survival percentage compared to controls. Two different recovery culture media were compared for their efficiency in survival. On average, the survival under in vitro culture conditions using optimized conditions was high: above 60% in majority of the accessions. Dormant buds showed viability in the range of 25 to 100% with an average of 50.4%. The recovery percentage of winter dormant buds after cryopreservation via slow freezing and slow thawing with rehydration by moist moss grass for 2 h was recorded in the range from 63.3 to 90.9% with an average of 81.05%. Without rehydration, it ranged from 50 to 75% with an average of 60.4%. Regeneration of cryopreserved mulberry germplasm after 6 years of storage indicated no survival loss over different years of storage, and 33-40% of the accessions showed viability above 40%, up to a maximum of 100%. Maximum shoot formation (100%) was obtained from Morus alba. The majority of the accessions were rooted in vitro within 20-25 days of subculture in the auxin rich rooting media, except in wild species M. latifolia and M. laevigata, which took longer (45 to 60 days) for root development. All the rooted plantlets were then transferred to the field and successfully established in a glasshouse.
PMID: 36678937
Plants (Basel) , IF:3.935 , 2023 Jan , V12 (1) doi: 10.3390/plants12010201
Grafting Causes Physiological Changes and Promotes Adventitious Root Formation in Rejuvenated Soft Shoots of Taxodium hybrid 'Zhongshanshan'.
Institute of Botany, Jiangsu Province and Chinese Academy of Sciences, Nanjing 210014, China.; Jiangsu Key Laboratory for the Research and Utilization of Plant Resources, Nanjing 210014, China.; Jingjiang Greening Engineering Co., Ltd., Jingjiang 214500, China.; College of Forestry and Agriculture, Stephen F. Austin State University, Nacogdoches, TX 75962, USA.
Taxodium hybrid 'Zhongshanshan' has been widely used as a timber tree in river network areas and coastal regions and is mainly propagated by cuttings. However, when trees age, their capacity to form adventitious roots becomes weaker. We successfully enhanced the rooting ability of shoots in T. hybrid 'Zhongshanshan 302' by their rejuvenation based on grafting. We recorded temporal variation in endogenous auxin, abscisic acid (ABA), gibberellins (GAs), trans-zeatin-riboside (TZR), soluble sugar and H(2)O(2) after root induction. Auxin, soluble sugars and H(2)O(2) levels were higher in rejuvenated shoots than in mature shoots, whereas the opposite was true for ABA and GAs. Notably, indole-3-acetic acid (IAA) and GA3 presented higher contents with more obvious differences in T. hybrid 'Zhongshanshan 302' rejuvenated shoots vs. mature shoots compared with other kinds of auxin and GAs. The evident improvement in the rooting ability of rejuvenated shoots after grafting likely resulted from the differential regulation of plant hormones, carbohydrates and redox signaling. In addition to the physiological basis of improved rooting ability by grafting, this study provided a theoretical basis for the optimization of subsequent propagation techniques in T. hybrid 'Zhongshanshan' and potentially other Taxodium spp.
PMID: 36616329
Plants (Basel) , IF:3.935 , 2023 Jan , V12 (1) doi: 10.3390/plants12010186
Characterizing Root Morphological Responses to Exogenous Tryptophan in Soybean (Glycine max) Seedlings Using a Scanner-Based Rhizotron System.
Department of International Agricultural Development, Tokyo University of Agriculture, 1-1-1 Sakuragaoka, Setagaya-ku, Tokyo 156-8502, Japan.; Gulf Coast Research and Education Center, Institute of Food and Agricultural Sciences, University of Florida, 14625 CR 672, Wimauma, FL 33598, USA.
Tryptophan is a precursor of indole-3-acetic acid (IAA), which is the major auxin involved in the regulation of lateral root formation. In this study, we used a scanner-based rhizotron system to examine root growth and morphological responses of soybean (Glycine max, 'Golden Harvest') seedlings to exogenous tryptophan. Seeds were sown directly in the rhizotron filled with field soil. Tryptophan was applied at 1.9 and 3.8 mg plant(-1) by soil drenching or foliar spray. Canopy and root projected area were monitored by analyzing canopy and rhizotron images using ImageJ software. Seedlings were sampled at the first trifoliate stage, 18 days after sowing (DAS), and root morphology was determined by analyzing washed root images using WinRHIZO software. According to contrast analysis, when all tryptophan treatments were pooled, tryptophan application increased canopy and root projected area by 13% to 14% compared with the control at 18 DAS. Tryptophan application also increased root dry matter accumulation by 26%, root:shoot ratio by 24%, and secondary root number by 13%. Tryptophan applied by soil drenching also increased root length and surface area of fine roots (<0.2 mm diameter) by 25% and 21%, respectively, whereas it slightly inhibited primary root elongation. The efficacy of tryptophan soil drenching in stimulating root formation became greater with increasing the application rate. These results suggest that exogenous tryptophan induces auxin-like activities in root development. Soil drenching of tryptophan appears to be an effective strategy in improving the establishment of soybean. Importantly, this strategy is easily implementable by commercial growers with no negative side effect.
PMID: 36616315
Am J Bot , IF:3.844 , 2023 Jan , V110 (1) : Pe16102 doi: 10.1002/ajb2.16102
What determines root-sprouting ability: Injury or phytohormones?
Department of Experimental and Functional Morphology, Institute of Botany of the Czech Academy of Sciences, Dukelska 135, CZ-379 82, Trebon, Czech Republic.; Laboratory of Hormonal Regulations in Plants, Institute of Experimental Botany of the Czech Academy of Sciences, Rozvojova 263, 165 02 Prague 6, Czech Republic.; Department of Ecology and Environmental Sciences, Palacky University, Slechtitelu 241/27, CZ-783 71, Olomouc, Czech Republic.; Department of Botany, Faculty of Science, Charles University, Benatska 2, CZ-128 01 Praha 2, Czech Republic.
PREMISE: Root-sprouting (RS) is an evolutionarily independent alternative to axillary stem branching for a plant to attain its architecture. Root-sprouting plants are better adapted to disturbance than non-RS plants, and their vigor is frequently boosted by biomass removal. Nevertheless, RS plants are rarer than plants that are not root-sprouters, possibly because they must overcome developmental barriers such as intrinsic phytohormonal balance or because RS ability is conditioned by injury to the plant body. The objective of this study was to identify whether phytohormones or injury enable RS. METHODS: In a greenhouse experiment, growth variables, root respiration, and phytohormones were analyzed in two closely related clonal herbs that differ in RS ability (spontaneously RS Inula britannica and rhizomatous non-RS I. salicina) with and without severe biomass removal. RESULTS: As previously reported, I. britannica is a root-sprouter, but injury did not boost its RS ability. Root respiration did not differ between the two species and decreased continuously with time irrespectively of injury, but their phytohormone profiles differed significantly. In RS species, the auxins-to-cytokinins ratio was low, and injury further decreased it. CONCLUSIONS: This first attempt to test drivers behind different plant growth forms suggests that intrinsic phytohormone regulation, especially the auxins-to-cytokinins ratio, might be behind RS ability. Injury, causing a phytohormonal imbalance, seems to be less important in spontaneously RS species than expected for RS species in general.
PMID: 36371783
Life (Basel) , IF:3.817 , 2023 Jan , V13 (1) doi: 10.3390/life13010170
Comparative Proteomics Analysis between Maize and Sorghum Uncovers Important Proteins and Metabolic Pathways Mediating Drought Tolerance.
Department of Biotechnology, University of the Western Cape, Robert Sobukwe Road, Bellville 7530, South Africa.; Centre for Bioinformatics and Computational Biology, Division of Molecular Biology and Human Genetics, Faculty of Medicine and Health Sciences, Stellenbosch University, Cape Town 7500, South Africa.; DSI-NRF Centre of Excellence in Food Security, University of the Western Cape, Robert Sobukwe Road, Bellville 7530, South Africa.
Drought severely affects crop yield and yield stability. Maize and sorghum are major crops in Africa and globally, and both are negatively impacted by drought. However, sorghum has a better ability to withstand drought than maize. Consequently, this study identifies differences between maize and sorghum grown in water deficit conditions, and identifies proteins associated with drought tolerance in these plant species. Leaf relative water content and proline content were measured, and label-free proteomics analysis was carried out to identify differences in protein expression in the two species in response to water deficit. Water deficit enhanced the proline accumulation in sorghum roots to a higher degree than in maize, and this higher accumulation was associated with enhanced water retention in sorghum. Proteomic analyses identified proteins with differing expression patterns between the two species, revealing key metabolic pathways that explain the better drought tolerance of sorghum than maize. These proteins include phenylalanine/tyrosine ammonia-lyases, indole-3-acetaldehyde oxidase, sucrose synthase and phenol/catechol oxidase. This study highlights the importance of phenylpropanoids, sucrose, melanin-related metabolites and indole acetic acid (auxin) as determinants of the differences in drought stress tolerance between maize and sorghum. The selection of maize and sorghum genotypes with enhanced expression of the genes encoding these differentially expressed proteins, or genetically engineering maize and sorghum to increase the expression of such genes, can be used as strategies for the production of maize and sorghum varieties with improved drought tolerance.
PMID: 36676117
J Appl Microbiol , IF:3.772 , 2023 Jan , V134 (1) doi: 10.1093/jambio/lxac013
Not just passengers, but co-pilots! Non-rhizobial nodule-associated bacteria promote cowpea growth and symbiosis with (brady)rhizobia.
Colegiado de Farmacia, Universidade Federal do Vale do Sao Francisco (Univasf), Petrolina, PE 56304-205, Brazil.; Universidade Estadual da Paraiba (UEPB), Campina Grande, PB 58429-500, Brazil.; Universidade Estadual de Feira de Santana (UEFS), Feira de Santana, Novo Horizonte, BA 44036-900, Brazil.; Instituto Federal de Educacao, Ciencia e Tecnologia do Para (IFPA), Campus Itaituba, Itaituba, PA 68183-300, Brazil.; Helmholtz Munich, German Research Center for Environmental Health, Neuherberg, Munich 85764, Germany.; Fundacao de Amparo a Pesquisa do Estado de Pernambuco (Facepe), Recife, PE 50720-001, Brazil.; Conselho Nacional de Desenvolvimento Cientifico e Tecnologico (CNPq), Brasilia, DF 71605-001, Brazil.; Embrapa Semiarido, Petrolina, PE 56302-970, Brazil.; Embrapa Agrobiologia, Seropedica, RJ 23897-970, Brazil.
AIMS: To isolate and characterize non-rhizobial nodule-associated bacteria (NAB) from cowpea root-nodules regarding their performance of plant-growth-promoting mechanisms and their ability to enhance cowpea growth and symbiosis when co-inoculated with bradyrhizobia. METHODS AND RESULTS: Sixteen NAB were isolated, identified, and in vitro evaluated for plant growth promotion traits. The ability to promote cowpea growth was analyzed when co-inoculated with Bradyrhizobium pachyrhizi BR 3262 in sterile and non-sterile substrates. The 16S rRNA gene sequences analysis revealed that NAB belonged to the genera Chryseobacterium (4), Bacillus (3), Microbacterium (3), Agrobacterium (1), Escherichia (1), Delftia (1), Pelomonas (1), Sphingomonas (1), and Staphylococcus (1). All strains produced different amounts of auxin siderophores and formed biofilms. Twelve out of the 16 strains carried the nifH, a gene associated with nitrogen fixation. Co-inoculation of NAB (ESA 424 and ESA 29) with Bradyrhizobium pachyrhizi BR 3262 significantly promoted cowpea growth, especially after simultaneous inoculation with the three strains. CONCLUSIONS: NAB are efficient cowpea growth promoters and can improve the efficiency of the symbiosis between cowpea and the N2-fixing microsymbiont B. pachyrhizi BR 3262, mainly under a specific triple microbial association.
PMID: 36626727
Gene , IF:3.688 , 2023 Jan , V851 : P146982 doi: 10.1016/j.gene.2022.146982
Molecular characterization of the GH3 family in alfalfa under abiotic stress.
Hainan Key Laboratory for the Sustainable Utilization of Tropical Bioresources, Hainan University, Haikou 570228, People's Republic of China; School of Tropical Crops, Hainan University, Haikou 570228, People's Republic of China.; College of Animal Science and Technology, Yangzhou University, Yangzhou 225009, People's Republic of China.; Hainan Key Laboratory for the Sustainable Utilization of Tropical Bioresources, Hainan University, Haikou 570228, People's Republic of China.; Alliance of Bioversity International and the International Center for Tropical Agriculture (CIAT), Cali 763537, Colombia.; Hainan University Archives, Haikou 570228, People's Republic of China.; Hainan Key Laboratory for the Sustainable Utilization of Tropical Bioresources, Hainan University, Haikou 570228, People's Republic of China; School of Tropical Crops, Hainan University, Haikou 570228, People's Republic of China. Electronic address: zhangrui@hainanu.edu.cn.; Hainan Key Laboratory for the Sustainable Utilization of Tropical Bioresources, Hainan University, Haikou 570228, People's Republic of China. Electronic address: yhchen@hainanu.edu.cn.
The phytohormone auxin plays a pivotal role in regulating plant growth, development, and abiotic stress responses by promptly controlling the expression of auxin response genes. The Gretchen Hagen3 (GH3) genes are a major early auxin response gene family that contribute to auxin homeostasis by conjugating excess auxins to amino acids. To our knowledge, a genome-wide investigation of the GH3 genes in alfalfa has never been reported. Here, we present a comprehensive bioinformatics analysis of the MsGH3 gene family, including chromosomal locations, phylogenetic relationships, gene structures, conserved motifs and Gene Ontology annotation. Interestingly, the analysis revealed 31 MsGH3 genes in the alfalfa genome. These genes were classified phylogenetically into the GH3-I, GH3-II, and GH3-III subgroups. Additionally, the data analysis showed that most MsGH3 genes are tissue specific and responsive to environmental stress-related hormones. Furthermore, the analysis of cis elements and potential biological functions revealed that the MsGH3 genes play potential roles in various stress responses. Notably, qRT-PCR results following exposure to high temperature, drought, and salt treatments demonstrated that most of the MsGH3 family genes, especially MsGH3-12, MsGH3-13, and MsGH3-15, play important roles in stress responses. These findings provide invaluable insight for future practical analyses and genetic improvement of alfalfa abiotic stress tolerance.
PMID: 36270456
J Plant Physiol , IF:3.549 , 2023 Feb , V282 : P153924 doi: 10.1016/j.jplph.2023.153924
'Yunnan' quince rootstock promoted flower bud formation of 'Abbe Fetel' pear by altering hormone levels and PbAGL9 expression.
College of Horticulture, Northwest A&F University, Yangling, Shaanxi Province, 712100, China. Electronic address: imcongliu@163.com.; College of Horticulture, Northwest A&F University, Yangling, Shaanxi Province, 712100, China. Electronic address: 17835697357@139.com.; College of Horticulture, Northwest A&F University, Yangling, Shaanxi Province, 712100, China. Electronic address: liushanshan215@yeah.net.; College of Horticulture, Northwest A&F University, Yangling, Shaanxi Province, 712100, China. Electronic address: wangazheng0322@163.com.; College of Horticulture, Northwest A&F University, Yangling, Shaanxi Province, 712100, China. Electronic address: zhongdishaonian@sina.com.; College of Horticulture, Northwest A&F University, Yangling, Shaanxi Province, 712100, China. Electronic address: cqyang@nwsuaf.edu.cn.; College of Horticulture, Northwest A&F University, Yangling, Shaanxi Province, 712100, China. Electronic address: wzhg001@163.com.; College of Horticulture, Northwest A&F University, Yangling, Shaanxi Province, 712100, China. Electronic address: lingfxu2013@sina.com.
Flower busd formation is an important plant growth process. It has been reported that dwarfing rootstocks can significantly affect the flower bud formation of scions. In this study, we found the dwarfing rootstock 'Yunnan' quince could significantly increase the flowering rate of 'Abbe Fetel' pear scions. The RNA-sequencing data revealed significant changes in the expression of genes related to hormone pathways. Furthermore, hormone analyses indicated that 'Yunnan' quince significantly decreased the GA(3) content and increased the cytokinin/auxin ratio in 'Abbe Fetel' pear apical buds. The hormone contents were consistent with the RNA-sequencing data. Moreover, we found the flower development-related genes PbAGL9 and PbCAL-A1 were significantly upregulated and PbTFL1 was significantly downregulated in 'Abbe Fetel'/'Yunnan' quince apical buds. To further clarify the relationship between hormones and flowering-related genes, a hormone response assay was carried out. We found the expression levels of PbCAl-A1, PbTFL1 and PbAGL9 were regulated by hormones including GA(3), CPPU and NAA. Y1H and dual-luciferase assays indicated that PbAGL9 significantly decreased the promoter activity of PbTFL1. In summary, 'Yunnan' quince upregulated PbCAL-A1 and PbAGL9, and downregulated PbTFL1 expression by decreasing the GA(3) content and increasing the cytokinin/auxin ratio in 'Abbe Fetel' pear apical buds. Additionally, 'Yunnan' quince down-regulate PbTFL1 by upregulating the expression of PbAGL9, and eventually promoted floral induction in 'Abbe Fetel' pear.
PMID: 36805518
J Plant Physiol , IF:3.549 , 2023 Jan , V282 : P153929 doi: 10.1016/j.jplph.2023.153929
PLDdelta, auxin, and H(2)O(2) mediated the allelopathic effect of cycloastragenol on root growth in Arabidopsis.
College of Life Science, Northwest Normal University, Lanzhou, 730070, China.; College of Life Science, Northwest Normal University, Lanzhou, 730070, China. Electronic address: xbsd-yn@163.com.
Cycloastragenol (CAG) is a tetra-cyclic triterpenoid allelochemical. It has been widely studied in animals but rarely in plants. Here, we reported that a model allelochemical CAG inhibited primary root elongation of Arabidopsis by reducing the sizes of both the meristem and elongation zones. Phospholipase Ddelta(PLDdelta), hydrogen peroxide (H(2)O(2)), and auxin affected this process. After treatment with CAG, the expression of PLDdelta and the activity of the Phospholipase D(PLD) enzyme increased in WT. Mutants analysis demonstrated that PLDdelta negatively regulated the primary root elongation by CAG treatment. CAG treatment stimulated the accumulation of H(2)O(2) in roots. The production of H(2)O(2) was derived from cell wall peroxidase. Mutants analysis showed that PLDdelta positively regulated the production of H(2)O(2) by CAG treatment. CAG also decreased auxin content in the root tip by affecting the expression of auxin synthesis-related genes. PLDdelta was involved in the auxin reduction mediated by CAG, but H(2)O(2) did not participate in this process. In conclusion, PLDdelta, auxin, and H(2)O(2) mediated the inhibition of primary root growth by CAG in Arabidopsis.
PMID: 36724592
J Plant Physiol , IF:3.549 , 2023 Jan , V282 : P153919 doi: 10.1016/j.jplph.2023.153919
Auxin alleviates cadmium toxicity by increasing vacuolar compartmentalization and decreasing long-distance translocation of cadmium in Poa pratensis.
College of Pratacultural Science, Gansu Agricultural University, Key Laboratory of Grassland Ecosystem, Ministry of Education, Pratacultural Engineering Laboratory of Gansu Province, Sino-U.S. Center for Grazingland Ecosystem Sustainability, Lanzhou, Gansu, 730070, China.; College of Pratacultural Science, Gansu Agricultural University, Key Laboratory of Grassland Ecosystem, Ministry of Education, Pratacultural Engineering Laboratory of Gansu Province, Sino-U.S. Center for Grazingland Ecosystem Sustainability, Lanzhou, Gansu, 730070, China. Electronic address: mahl@gsau.edu.cn.
Kentucky bluegrass (Poa pratensis L.) hyperaccumulates cadmium (Cd) and exhibits a hypertolerance. Thus, it has potential for the phytoremediation of Cd-containing soil. Auxin signaling is involved in the response to Cd stress. However, the mechanisms of auxin-mediated detoxification and Cd translocation in plants remain unclear. This study aimed to investigate the effects of exogenous application of indole-3-acetic acid (IAA) on the Cd translocation, subcellular Cd distribution, chemical forms of Cd, and transcriptional regulation of Kentucky bluegrass. The results showed that the exogenous application of IAA increased the amount of organelle-bound Cd and vacuole-compartmentalized Cd in root cells, reduced the Cd concentration in the leaf tissues (epidermis, mesophyll, and vascular bundle) and root tissues (rhizodermis and cortex) but increased in the stele, and alleviate Cd-induced leaf chlorosis and growth inhibition. The expression of genes associated with Cd transporters (ABCs, ZIPs, NASs, OPTs, and YSLs), phosphatases, oxalate decarboxylases and lignin biosynthesis were significantly regulated by exogenous IAA under Cd stress. A positive regulation of phosphatases and oxalate decarboxylases genes related to an increase in phosphate- and oxalate-bound Cd, as well as a decrease in pectate- and protein-bound Cd and inorganic Cd, thereby contributing to a decrease in Cd phytotoxicity. The significant regulation of Cd transporters associated with decreasing the long-distance translocation of Cd, and the activation of lignin biosynthesis may contribute to the development of root endodermal barriers and increase the deposition of undissolved Cd phosphates and oxalate-bound Cd in the stele. These results revealed the important role of auxin in Cd detoxification and translocation in Kentucky bluegrass and they provide a theoretical basis for the phytoremediation of Cd-containing soil.
PMID: 36706576
J Plant Physiol , IF:3.549 , 2023 Feb , V281 : P153920 doi: 10.1016/j.jplph.2023.153920
Transcriptome and anatomical studies reveal alterations in leaf thickness under long-term drought stress in tobacco.
Key Laboratory of Tobacco Biology and Processing, Ministry of Agriculture and Rural Affairs, Tobacco Research Institute, Chinese Academy of Agricultural Sciences, Qingdao, 266101, China.; Key Laboratory of Tobacco Biology and Processing, Ministry of Agriculture and Rural Affairs, Tobacco Research Institute, Chinese Academy of Agricultural Sciences, Qingdao, 266101, China. Electronic address: maxinghua@caas.cn.; State Key Laboratory of Subtropical Silviculture, Zhejiang A&F University, 666 Wusu Street, Hangzhou, 311300, China.; Guangxi Key Laboratory of Agric-Environment and Agric-Products Safety, Agricultural College of Guangxi University, Nanning, 530004, China.; Department of Agronomy, The University of Agriculture, Peshawar, 25130, Khyber Pakhtunkhwa, Pakistan.; Key Laboratory of Tobacco Biology and Processing, Ministry of Agriculture and Rural Affairs, Tobacco Research Institute, Chinese Academy of Agricultural Sciences, Qingdao, 266101, China. Electronic address: shiyi@caas.cn.
Drought is one of the foremost environmental factors that limit the growth of plants. Leaf thickness (LT) is an important quantitative trait in plant physiology. The experiment was carried out in a growth room and the plants were divided into two groups such as well-watered and drought-stressed. This work investigated leaf growth in terms of leaf surface growth and expansion rate, leaf stomata traits, LT, anticlinal growth, and leaf cell layers. The results showed that the leaf area and leaf surface expansion rate were decreased by drought stress (DS). Similarly, LT, anticlinal expansion rate, palisade and spongy tissue thickness, and their related expansion rates were also decreased at different days' time points (DTP) of DS. However, a steady increase was observed in the aforementioned parameters after 12 DTP of DS. The stomatal density increased while stomata size decreased at 3 DTP and 12 DTP (low leaf water potential and relative leaf water content at these time points) and vice versa at 24 DTP compared with the well-watered plants indicating adaptations in these traits in response to DS, and thus the leaf water status played a role in the regulation of leaf stomata traits. The cell length decreased in the upper epidermis, palisade and spongy tissues by DS up to 12 DTP led to lower LT while an increase was observed after 12 DTP that resulted in higher LT. The increase in the LT was supported by the upregulation of starch and sucrose metabolism, glycerolipid metabolism, protein processing in endoplasmic reticulum pathways at 18 DTP along with the differentially expressed genes induced that were related to cell wall remodeling (cellulose, expansin, xyloglucans) and cell expansion (auxin response factors and aquaporin). The results explain the response of leaf thickness to drought stress and show alterations in LT and leaf stomatal traits. This study might serve as a valuable source of gene information for functional studies and provide a theoretical basis to understand leaf growth in terms of leaf anatomy and leaf stomatal traits under drought stress.
PMID: 36680840
J Plant Physiol , IF:3.549 , 2023 Jan , V280 : P153891 doi: 10.1016/j.jplph.2022.153891
The nitrification inhibitor 1,9-decanediol from rice roots promotes root growth in Arabidopsis through involvement of ABA and PIN2-mediated auxin signaling.
State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, Nanjing, 210008, China; University of Chinese Academy of Sciences, Beijing, 100049, China.; State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, Nanjing, 210008, China. Electronic address: yflu@issas.ac.cn.; State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, Nanjing, 210008, China.; School of BioSciences, The University of Melbourne, Parkville, VIC, 3010, Australia.; Amway (China) Botanical R&D Center, Wuxi, 214115, China.; State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, Nanjing, 210008, China; University of Chinese Academy of Sciences, Beijing, 100049, China. Electronic address: wmshi@issas.ac.cn.
1,9-decanediol (1,9-D) is a biological nitrification inhibitor secreted in roots, which effectively inhibits soil nitrifier activity and reduces nitrogen loss from agricultural fields. However, the effects of 1,9-D on plant root growth and the involvement of signaling pathways in the plant response to 1,9-D have not been investigated. Here, we report that 1,9-D, in the 100-400 muM concentration range, promotes primary root length in Arabidopsis seedlings at 3d and 5d, by 10.1%-33.3% and 6.9%-32.6%, and, in a range of 50-200 muM, leads to an increase in the number of lateral roots. 150 muM 1,9-D was found optimum for the positive regulation of root growth. qRT-PCR analysis reveals that 1,9-D can significantly increase AtABA3 gene expression and that a mutation in ABA3 results in insensitivity of root growth to 1,9-D. Moreover, through pharmacological experiments, we show that exogenous addition of ABA (abscisic acid) with 1,9-D enhances primary root length by 23.5%-63.3%, and an exogenous supply of 1,9-D with the ABA inhibitor Flu reduces primary root length by 1.0%-14.3%. Primary root length of the pin2/eir1-1 is shown to be insensitive to both exogenous addition of 1,9-D and ABA, indicating that the auxin carrier PIN2/EIR1 is involved in promotion of root growth by 1,9-D. These results suggest a novel for 1,9-D in regulating plant root growth through ABA and auxin signaling.
PMID: 36495813
Protoplasma , IF:3.356 , 2023 Jan doi: 10.1007/s00709-022-01833-3
Auxin- and pH-induced guttation in Phycomyces sporangiophores: relation between guttation and diminished elongation growth.
Institute for Multidisciplinary Research, University of Belgrade, Kneza Viseslava 1, 11030, Belgrade, Serbia. vunduk@imsi.bg.ac.rs.; Max Planck Institute for Evolutionary Biology, Department of Evolutionary Biology, August Thienemann Str. 2, 24306, Plon, Germany.; Institute for Multidisciplinary Research, University of Belgrade, Kneza Viseslava 1, 11030, Belgrade, Serbia.; Singidunum University, Danijelova 32, 11010, Belgrade, Serbia.; Faculty of Biology, Philipps-University Marburg, Karl-Von-Frisch Str. 8, 35032, Marburg, Germany.
Guttation, the formation of exudation water, is widespread among plants and fungi, yet the underlying mechanisms remain largely unknown. We describe the conditions for inducing guttation in sporangiophores of the mucoracean fungus, Phycomyces blakesleeanus. Cultivation on peptone-enriched potato dextrose agar elicits vigorous guttation mainly below the apical growing zone, while sporangiophores raised on a glucose-mineral medium manifest only moderate guttation. Mycelia do not guttate irrespective of the employed media. The topology of guttation droplets allows identifying the non-growing part of the sporangiophore as a guttation zone, which responds to humidity and medium composition in ways that become relevant for turgor homeostasis and thus the sensor physiology of the growing zone. Apparently, the entire sporangiophore, rather than exclusively the growing zone, participates in signal reception and integration to generate a common growth output. Exogenous auxin applied to the growing zones elicits two correlated responses: (i) formation of guttation droplets in the growing and transition zones below the sporangium and (ii) a diminution of the growth rate. In sporangiophore populations, guttation-induction by exogenous control buffer occurs at low frequencies; the bias for guttation increases with increasing auxin concentration. Synthetic auxins and the transport inhibitor NPA suppress guttation completely, but leave growth rates largely unaffected. Mutants C2 carA and C148 carA madC display higher sensitivities for auxin-induced guttation compared to wild type. A working model for guttation includes aquaporins and mechanosensitive ion channels that we identified in Phycomyces by sequence domain searches.
PMID: 36622433
Protoplasma , IF:3.356 , 2023 Jan , V260 (1) : P257-270 doi: 10.1007/s00709-022-01773-y
Genome-wide identification of Aux/IAA and ARF gene families in bread wheat (Triticum aestivum L.).
Department of Plant Molecular Biology, University of Delhi South Campus, New Delhi, 110021, India.; Department of Plant Molecular Biology, University of Delhi South Campus, New Delhi, 110021, India. param@genomeindia.org.
Wheat (Triticum aestivum L.) is one of the most important food crops in the world. Somatic embryogenesis is an event that is triggered by the presence of auxin hormone for the induction of somatic cells to get converted to embryonic cells. Somatic embryogenesis represents the most important process of totipotency of plants. The role of auxins is widely understood during various stages of embryogenesis including polarity establishment, de-differentiation, re-differentiations, and morphogenesis. Many of the Aux/IAAs and ARFs which are part of auxin signaling components have been identified to play various roles during embryogenesis. In this analysis, the Aux/IAAs and ARFs of T. aestivum have been analyzed at the genome-scale; their structure, function, and evolutionary relatedness were determined. Several Aux/IAAs and ARFs components of T. aestivum have been found to exclusively regulate axis formation, meristem commitment, and other re-differentiation processes by differential expression studies.
PMID: 35606614
Funct Plant Biol , IF:3.101 , 2023 Jan , V50 (1) : P58-70 doi: 10.1071/FP22002
Crucial role of Arabidopsis glutaredoxin S17 in heat stress response revealed by transcriptome analysis.
State Key Laboratory of Biocatalysis and Enzyme Engineering, School of Life Sciences, Hubei University, Wuhan 430062, P. R. China.; USDA/ARS Children's Nutrition Research Center, Department of Pediatrics, Baylor College of Medicine, Houston, TX 77030, USA.
Heat stress can have detrimental effects on plant growth and development. However, the mechanisms by which the plant is able to perceive changes in ambient temperature, transmit this information, and initiate a temperature-induced response are not fully understood. Previously, we showed that heterologous expression of an Arabidopsis thaliana L. monothiol glutaredoxin AtGRXS17 enhances thermotolerance in various crops, while disruption of AtGRXS17 expression caused hypersensitivity to permissive temperature. In this study, we extend our investigation into the effect of AtGRXS17 and heat stress on plant growth and development. Although atgrxs17 plants were found to exhibit a slight decrease in hypocotyl elongation, shoot meristem development, and root growth compared to wild-type when grown at 22 degrees C, these growth phenotypic differences became more pronounced when growth temperatures were raised to 28 degrees C. Transcriptome analysis revealed significant changes in genome-wide gene expression in atgrxs17 plants compared to wild-type under conditions of heat stress. The expression of genes related to heat stress factors, auxin response, cellular communication, and abiotic stress were altered in atgrxs17 plants in response to heat stress. Overall, our findings indicate that AtGRXS17 plays a critical role in controlling the transcriptional regulation of plant heat stress response pathways.
PMID: 36099929
Plant Biol (Stuttg) , IF:3.081 , 2023 Feb doi: 10.1111/plb.13511
Nitric oxide, calmodulin and calcium protein kinase interactions in the response of Brassica napus to salinity stress.
Department of Plant Biology, Faculty of basic sciences, Tarbiat Modares University, Tehran, Iran.
Involvement of nitric oxide (NO) in plant metabolism and its connection with phytohormones has not been fully described, thus information about the role of this molecule in signaling pathways remains fragmented. Therefore, in this study, the effects of NO on calmodulin (CAM), calcium protein kinase (CPK), the content of phytohormones and secondary metabolites in canola plants under salinity stress conditions were investigated. 100 muM sodium nitroprusside as an NO source were applied to canola plants grown under saline (100 mM NaCl) and non-saline conditions at vegetative stage. Plant growth was negatively affected by salinity conditions but exogenous NO treatment improved this parameter. NO caused a significant increase in activities of catalase (CAT), superoxide dismutase (SOD) and peroxidases (POX) due to enhancing CAT, SOD and POX expression in stressed-canola plants. Salinity-responsive genes, namely CAM and CPK, were induced by NO in plants grown under salinity conditions. NO application enhanced phenolic compounds such as gallic acid and coumaric acid and flavonoid compounds included catechin, diadzein and kaempferol in plants subjected to salinity. NO treatment enhanced abscisic acid and brassinosteroid, but declined auxin and gibberellin in stressed-canola plants. The impacts of NO on improving tolerance stress in canola were dependent on prompting CAM and CPK. Also, NO-signaling role re-established the phytohormones balance and resulted enhancement in plants tolerance to the salt stress. Too, NO improved salinity tolerance in canola plant by increasing enzymatic and non-enzymatic antioxidants.
PMID: 36779525
Plant Biol (Stuttg) , IF:3.081 , 2023 Mar , V25 (2) : P308-321 doi: 10.1111/plb.13489
Cold stress triggers freezing tolerance in wheat (Triticum aestivum L.) via hormone regulation and transcription of related genes.
College of Life Science, Northeast Agricultural University, Harbin, China.
Low temperatures limit the geographic distribution and yield of plants. Hormones play an important role in coordinating the growth and development of plants and their tolerance to low temperatures. However, the mechanisms by which hormones affect plant resistance to extreme cold stress in the natural environment are still unclear. In this study, two winter wheat varieties with different cold resistances, Dn1 and J22, were used to conduct targeted plant hormone metabolome analysis on the tillering nodes of winter wheat at 5 degrees C, -10 degrees C and -25 degrees C using an LC-ESI-MS/MS system. We screened 39 hormones from 88 plant hormone metabolites and constructed a partial regulatory network of auxin, jasmonic acid and cytokinin. GO analysis and enrichment of KEGG pathways in different metabolites showed that the 'plant hormone signal transduction' pathway was the most common. Our study showed that extreme low temperature increased the most levels of auxin, cytokinin and salicylic acid, and decreased levels of jasmonic acid and abscisic acid, and that levels of auxin, jasmonic acid and cytokinin in Dn1 were higher than those in J22. These changes in hormone levels were associated with changes in gene expression in synthesis, catabolism, transport and signal transduction pathways. These results differ from the previous hormone regulation mechanisms, which were mostly obtained at 4 degrees C. Our results provide a basis for further understanding the molecular mechanisms by which plant endogenous hormones regulate plant freezing stress tolerance.
PMID: 36385725
PeerJ , IF:2.984 , 2023 , V11 : Pe14581 doi: 10.7717/peerj.14581
Stem transcriptome screen for selection in wild and cultivated pitahaya (Selenicereus undatus): an epiphytic cactus with edible fruit.
Universidad Autonoma Metropolitana Iztapalapa, Ciudad de Mexico, Mexico.; INBIOTECA, Universidad Veracruzana, Xalapa, Veracruz, Mexico.; Biologia Evolutiva, Instituto de Ecologia AC, Xalapa, Veracruz, Mexico.
Dragon fruit, pitahaya or pitaya are common names for the species in the Hylocereus group of Selenicereus that produce edible fruit. These Neotropical epiphytic cacti are considered promising underutilized crops and are currently cultivated around the world. The most important species, S. undatus, has been managed in the Maya domain for centuries and is the focus of this article. Transcriptome profiles from stems of wild and cultivated plants of this species were compared. We hypothesized that differences in transcriptomic signatures could be associated with genes related to drought stress. De novo transcriptome assembly and the analysis of differentially expressed genes (DEGs) allowed us to identify a total of 9,203 DEGs in the Hunucma cultivar relative of wild Mozomboa plants. Of these, 4,883 represent up-regulated genes and 4,320, down-regulated genes. Additionally, 6,568 DEGs were identified from a comparison between the Uman cultivar and wild plants, revealing 3,286 up-regulated and 3,282 down-regulated genes. Approximately half of the DEGs are shared by the two cultivated plants. Differences between the two cultivars that were collected in the same region could be the result of differences in management. Metabolism was the most representative functional category in both cultivars. The up-regulated genes of both cultivars formed a network related to the hormone-mediated signaling pathway that includes cellular responses to auxin stimulus and to hormone stimulus. These cellular reactions have been documented in several cultivated plants in which drought-tolerant cultivars modify auxin transport and ethylene signaling, resulting in a better redistribution of assimilates.
PMID: 36632141
PeerJ , IF:2.984 , 2023 , V11 : Pe14617 doi: 10.7717/peerj.14617
Integrative genomic and transcriptomic analyses of a bud sport mutant 'Jinzao Wuhe' with the phenotype of large berries in grapevines.
The Research Institute of Forestry and Pomology, Tianjin Academy of Agricultural Sciences, Tianjin, China.; Institute of Crop Germplasm and Biotechnology, Tianjin Academy of Agricultural Sciences, Tianjin, China.; College of Biotechnology and Food Science, Tianjin University of Commerce, Tianjin, China.; College of Horticulture and Gardening, Tianjin Agricultural University, Tianjin, China.
BACKGROUND: Bud sport mutation occurs frequently in fruit plants and acts as an important approach for grapevine improvement and breeding. 'Jinzao Wuhe' is a bud sport of the elite cultivar 'Himord Seedless' with obviously enlarged organs and berries. To date, the molecular mechanisms underlying berry enlargement caused by bud sport in grapevines remain unclear. METHODS: Whole genome resequencing (WGRS) was performed for two pairs of bud sports and their maternal plants with similar phenotype to identify SNPs, InDels and structural variations (SVs) as well as related genes. Furthermore, transcriptomic sequencing at different developmental stages and weighted gene co-expression network analysis (WGCNA) for 'Jinzao Wuhe' and its maternal plant 'Himord Seedless' were carried out to identify the differentially expressed genes (DEGs), which were subsequently analyzed for Gene Ontology (GO) and function annotation. RESULTS: In two pairs of enlarged berry bud sports, a total of 1,334 SNPs, 272 InDels and 74 SVs, corresponding to 1,022 target genes related to symbiotic microorganisms, cell death and other processes were identified. Meanwhile, 1,149 DEGs associated with cell wall modification, stress-response and cell killing might be responsible for the phenotypic variation were also determined. As a result, 42 DEGs between 'Himord Seedless' and 'Jinzao Wuhe' harboring genetic variations were further investigated, including pectin esterase, cellulase A, cytochromes P450 (CYP), UDP-glycosyltransferase (UGT), zinc finger protein, auxin response factor (ARF), NAC transcription factor (TF), protein kinase, etc. These candidate genes offer important clues for a better understanding of developmental regulations of berry enlargement in grapevine. CONCLUSION: Our results provide candidate genes and valuable information for dissecting the underlying mechanisms of berry development and contribute to future improvement of grapevine cultivars.
PMID: 36620751
Ecotoxicology , IF:2.823 , 2023 Jan , V32 (1) : P1-11 doi: 10.1007/s10646-022-02613-8
Pea root responses under naproxen stress: changes in the formation of structural barriers in the primary root in context with changes of auxin and abscisic acid levels.
Section of Experimental Plant Biology, Department of Experimental Biology, Faculty of Science, Masaryk University Brno, Kotlarska 2, 611 37, Brno, Czech Republic.; Section of Experimental Plant Biology, Department of Experimental Biology, Faculty of Science, Masaryk University Brno, Kotlarska 2, 611 37, Brno, Czech Republic. zezulka@sci.muni.cz.; Department of Plant Physiology, Faculty of Natural Science, Comenius University in Bratislava, Mlynska dolina B2, 842 15, Bratislava, Slovakia.; Institute of Plant Biology, Faculty of Agronomy, Mendel University Brno, Zemedelska 1, 613 00, Brno, Czech Republic.; Laboratory of Metabolomics and Isotope Analyses, Global Change Research Institute, Czech Academy of Sciences, Belidla 986/4a, 603 00, Brno, Czech Republic.
Pharmaceuticals belong to pseudo-persistent pollutants because of constant entry into the environment and hazardous potential for non-target organisms, including plants, in which they can influence biochemical and physiological processes. Detailed analysis of results obtained by microscopic observations using fluorescent dyes (berberine hemisulphate, Fluorol Yellow 088), detection of phytohormone levels (radioimmunoassay, enzyme-linked immune sorbent assay) and thermogravimetric analysis of lignin content proved that the drug naproxen (NPX) can stimulate the formation of root structural barriers. In the primary root of plants treated with 0.5, 1, and 10 mg/L NPX, earlier Casparian strip formation and development of the whole endodermis circle closer to its apex were found after five days of cultivation (by 9-20% as compared to control) and after ten days from 0.1 mg/L NPX (by 8-63%). Suberin lamellae (SL) were deposited in endodermal cells significantly closer to the apex under 10 mg/L NPX by up to 75%. Structural barrier formation under NPX treatment can be influenced indirectly by auxin-supported cell division and differentiation caused by its eight-times higher level under 10 mg/L NPX and directly by stimulated SL deposition induced by abscisic acid (higher from 0.5 mg/L NPX), as proved by the higher proportion of cells with SL in the primary root base (by 8-44%). The earlier modification of endodermis in plant roots can help to limit the drug transfer and maintain the homeostasis of the plant.
PMID: 36542231
Transgenic Res , IF:2.788 , 2023 Feb doi: 10.1007/s11248-023-00337-x
Functional characterization of transcriptional activator gene SIARRI in tomato reveals its role in fruit growth and ripening.
College of Agriculture and Biotechnology, Zhejiang University, Hangzhou, 310058, China.; Department of Plant Protection, Faculty of Agricultural Sciences and Technology, Sivas University of Science and Technology, 58140, Sivas, Turkey.; Department of Horticulture, MNS University of Agriculture, Multan, 60000, Pakistan.; Department of Horticulture, Faculty of Crop Production Sciences, The University of Agriculture Peshawar, Peshawar, 25120, Pakistan.; Department of Plant Breeding and Genetics, University College of Agriculture, Bahauddin Zakariya University, Multan, Pakistan.; Department of Field Crops, Faculty of Agriculture, Institute of Natural and Applied Sciences, Cukurova University, 01330, Adana, Turkey.; North Florida Research and Education Centre (NFREC), University of Florida, 155 Research Road, Quincy, FL, 32351, USA.; Department of Horticulture, Faculty of Agriculture, Ondokuz Mayis University, Samsun, Turkey.; Department of Biological and Geological Sciences, Faculty of Education, Ain Shams University, Cairo, 11341, Egypt. hebaibrahim79@gmail.com.
Auxins regulate several characteristics of plant development and growth. Here, we characterized a new transcriptional activator SIARRI which binds specific DNA sequences and was revealed in Arabidopsis (ARR1). SIARRI acts as a two-component response regulator and its Arabidopsis homologous gene is AT3G16857. It belongs to the subfamily of type-B response regulators in the cytokinin signaling pathway. The study aimed to characterize the transgenic Micro-Tom plants by the overexpression of Solanum lycopersicum two-component response regulator ARR1. Overexpression of SIARRI results in a pleiotropic phenotype during fruit development and ripening. This study indicates that SIARRI is a primary regulator of leaf morphology and fruit development. Moreover, overexpressed plants showed variations in growth related to auxin as well as shorter hypocotyl elongation, enlarged leaf vascularization, and decreased apical dominance. The qRT-PCR investigation revealed that expression was downregulated at the breaker stage and high at Br+6 at various stages of fruit growth and ripening. In contrast to the fruit color, lycopene and beta-carotene concentrations in red-yellow overexpression line fruits were reduced significantly, and also slightly reduced in some red fruits. The quantity of beta-carotene in the transgenic fruits was lower than that of lycopene. This study showed that this gene might be a new transcriptional activator in fruit development and ripening. Furthermore, this study will provide new insights into tomato fruit ripening.
PMID: 36806962
Mol Biotechnol , IF:2.695 , 2023 Jan doi: 10.1007/s12033-023-00653-x
Loss-of-Function Mutation of ACTIN-RELATED PROTEIN 6 (ARP6) Impairs Root Growth in Response to Salinity Stress.
Faculty of Pharmacy, Ton Duc Thang University, Ho Chi Minh, Vietnam.; National Institute of Medicinal Materials, Hanoi, Vietnam.; Faculty of Biotechnology, Ho Chi Minh City Open University, 97 Vo Van Tan Street, District 3, Ho Chi Minh, Vietnam.; Faculty of Biotechnology, Ho Chi Minh City Open University, 97 Vo Van Tan Street, District 3, Ho Chi Minh, Vietnam. nguyen.nhoai@ou.edu.vn.
H2A.Z-containing nucleosomes have been found to function in various developmental programs in Arabidopsis (e.g., floral transition, warm ambient temperature, and drought stress responses). The SWI2/SNF2-Related 1 Chromatin Remodeling (SWR1) complex is known to control the deposition of H2A.Z, and it has been unraveled that ACTIN-RELATED PROTEIN 6 (ARP6) is one component of this SWR1 complex. Previous studies showed that the arp6 mutant exhibited some distinguished phenotypes such as early flowering, leaf serration, elongated hypocotyl, and reduced seed germination rate in response to osmotic stress. In this study, we aimed to investigate the changes of arp6 mutant when the plants were grown in salt stress condition. The phenotypic observation showed that the arp6 mutant was more sensitive to salt stress than the wild type. Upon salt stress condition, this mutant exhibited attenuated root phenotypes such as shorter primary root length and fewer lateral root numbers. The transcript levels of stress-responsive genes, ABA INSENSITIVE 1 (ABI1) and ABI2, were found to be impaired in the arp6 mutant in comparison with wild-type plants in response to salt stress. In addition, a meta-analysis of published data indicated a number of genes involved in auxin response were induced in arp6 mutant grown in non-stress condition. These imply that the loss of H2A.Z balance (in arp6 mutant) may lead to change stress and auxin responses resulting in alternative root morphogenesis upon both normal and salinity stress conditions.
PMID: 36627550
Arch Microbiol , IF:2.552 , 2022 Dec , V205 (1) : P45 doi: 10.1007/s00203-022-03358-y
Molecular identification and characterization of phytobeneficial osmotolerant endophytic bacteria inhabiting root nodules of the Saharan tree Vachellia tortilis subsp. raddiana.
Microbiology and Molecular Biology Team, Center of Plant and Microbial Biotechnology, Biodiversity and Environment, Faculty of Sciences, Mohammed V University in Rabat, Avenue Ibn Battouta, BP 1014, 10000, Rabat, Morocco.; Microbiology and Molecular Biology Team, Center of Plant and Microbial Biotechnology, Biodiversity and Environment, Faculty of Sciences, Mohammed V University in Rabat, Avenue Ibn Battouta, BP 1014, 10000, Rabat, Morocco. jamal.aurag@fsr.um5.ac.ma.
Nodular endophytes of drought-tolerant legumes are understudied. For this reason, we have isolated and studied non-symbiotic endophytic bacteria from nodules of Vachellia tortilis subsp. raddiana, a leguminous tree adapted to the harsh arid climate of Southern Morocco. Rep-PCR analysis followed by 16S rDNA sequencing revealed two main genera, Pseudomonas and Bacillus. Isolates responded variably to salt and water stresses, and mostly produced exopolysaccharides. Differences concerned also plant growth-promoting activities: phosphate, potassium, and zinc solubilization; biological nitrogen fixation; auxin, siderophore, ammonia, and HCN production; and ACC deaminase activity. Some strains exhibited antagonistic activities against phytopathogenic fungi (Fusarium oxysporum and Botrytis cinerea) and showed at least two enzymatic activities (cellulase, protease, chitinase). Four selected strains inoculated to vachellia plants under controlled conditions have shown significant positive impacts on plant growth parameters. These strains are promising bio-inoculants for vachellia plants to be used in reforestation programs in arid areas increasingly threatened by desertification.
PMID: 36576567
Braz J Microbiol , IF:2.476 , 2023 Mar , V54 (1) : P397-406 doi: 10.1007/s42770-022-00874-3
Bacillus subtilis and Bacillus licheniformis promote tomato growth.
Departamento de Fitopatologia, Universidade Federal de Lavras, Lavras, MG, 37200-900, Brazil.; Chr-Hansen Industria E Comercio Ltda, Valinhos, SP, 13278-327, Brazil.; Embrapa Meio Ambiente, Rod. SP-340 Km 1275, 13.918-110, Jaguariuna, SP, Brazil. wagner.bettiol@embrapa.br.
Bacillus spp. are widely marketed and used in agricultural systems as antagonists to various phytopathogens, but it can also benefit the plant as plant growth promoters. Therefore, the longer presence of the bacterium in the rhizosphere would result in a prolonged growth-promoting benefit, but little is yet known about its persistence in the rhizosphere after seed coating. The objectives of this study were to evaluate the tomato growth promotion mediated by Bacillus licheniformis FMCH001 and Bacillus subtilis FMCH002 and the survival rate of these bacteria both in shoots and in the rhizosphere. The Bacillus strains used throughout this study were obtained from Quartzo(R) produced by Chr. Hansen. The application of a mixture of B. subtilis and B. licheniformis (Quartzo(R)) at concentrations 1 x 10(8), 1 x 10(9), and 1 x 10(10) CFU mL(-1), as well as the application of B. subtilis and B. licheniformis individually at concentration 1 x 10(8) CFU mL(-1), increased fresh and dry masses of shoot and root system, volume of root system, and length of roots of tomato plants when compared to control. Both Bacillus strains produced IAA after 48 h of in vitro. Bacillus colonies obtained from plant sap were morphologically similar to colonies of B. subtilis and B. licheniformis strains and were detected in inoculated on plants and not detected in control ones. A similar pattern was obtained through DNA-based detection (qPCR). Therefore, B. subtilis and B. licheniformis were able to produce auxin, promote tomato growth, and colonize and persist in the rhizosphere.
PMID: 36422850
Can J Microbiol , IF:2.419 , 2023 Feb , V69 (2) : P103-116 doi: 10.1139/cjm-2022-0181
Bacterial secondary metabolites: possible mechanism for weed suppression in wheat.
Department of Soil Science, The Islamia University of Bahawalpur, Bahawalpur, Punjab 63100, Pakistan.; Institute of Agricultural Sciences in the Tropics (Hans-Ruthenberg-Institute), University of Hohenheim, Germany.; Institute of Soil and Environmental Sciences, University of Agriculture, Faisalabad, Punjab 38040, Pakistan.
Chemical weed control is an effective method, but has proved hazardous for humans, environment, and soil biodiversity. Use of allelopathic bacteria may be more efficient and sustainable weed control measure. The bacterial inoculants have never been studied in context of their interaction with weed root exudates and precursor-dependent production of the natural phytotoxins (cyanide, cytolytic enzymes and auxin) by these strains to understand their weed suppression and wheat growth promotion abilities. Therefore, root exudates of Avena fatua, Phalaris minor, Rumex dentatus, and wheat were quantified and their role in microbial root colonization and secondary metabolite production, i.e., cyanide, cytolytic enzymes, phenolics, and elevated auxin concentration, was studied. The results depicted l-tryptophan and glycine as major contributors of elevated cyanide and elevated levels in weed rhizosphere by the studied Pseudomonas strains, through their higher root colonization ability in weeds as compared with wheat. Furthermore, the higher root colonization also enhanced p-coumaric acid (photosynthesis inhibitor by impairing cytochrome c oxidase activity in plants) and cytolytic enzyme (root cell wall degradation) concentration in weed rhizosphere. In conclusion, the differential root colonization of wheat and weeds by these strains is responsible for enhancing weed suppression (enhancing phytotoxic effect) and wheat growth promotion (lowering phytotoxic effect).
PMID: 36379032
Can J Microbiol , IF:2.419 , 2023 Feb , V69 (2) : P88-102 doi: 10.1139/cjm-2022-0074
Neighbours in nodules: the interactions between Frankia sp. ACN10a and non-Frankia nodular endophytes of alder.
Centre SEVE, Departement de biologie, Faculte des Sciences, Universite de Sherbrooke, 2500 boulevard de l'Universite, Sherbrooke, Quebec, Canada, J1K 2R1.
In the present study, we report the in vitro interactions between Frankia sp. ACN10a and non-Frankia nodular endophytes (NFNE) isolated from alder. The supernatant of NFNE grown in nitrogen-replete medium had neutral or negative effects on Frankia growth; none had a stimulatory effect. Inhibitory effects were observed for supernatants of some NFNE, notably Micromonospora, Pseudomonas, Serratia and Stenotrophomonas isolates. However, some NFNE-Frankia coculture supernatants could stimulate Frankia growth when used as a culture medium supplement. This was observed for supernatants of Frankia cocultured with Microvirga and Streptomyces isolates. In nitrogen-limited conditions, cocultures of Frankia with some NFNE, including some rhizobia and Cytobacillus, resulted in higher total biomass than Frankia-only cultures, suggesting cooperation, while other NFNE were strongly antagonistic. Microscopic observation of cocultures also revealed compromised Frankia membrane integrity, and some differentiation into stress resistance-associated morphotypes such as sporangia and reproductive torulose hyphae (RTH). Furthermore, the coculture of Frankia with Serratia sp. isolates resulted in higher concentrations of the auxinic plant hormone indole-3-acetic acid and related indolic compounds in the culture supernatant. This study sheds new light on the breadth of microbial interactions that occur amongst bacteria that inhabit the understudied ecological niche of the alder nodule.
PMID: 36288608
Can J Microbiol , IF:2.419 , 2023 Feb , V69 (2) : P72-87 doi: 10.1139/cjm-2022-0073
Deciphering the role of non-Frankia nodular endophytes in alder through in vitro and genomic characterization.
Centre SEVE, Departement de biologie, Faculte des Sciences, Universite de Sherbrooke, 2500 boulevard de l'Universite, Sherbrooke, Quebec, Canada, J1K 2R1.
Endophytic bacterial populations are well-positioned to provide benefits to their host plants such as nutrient acquisition and plant hormone level manipulation. Actinorhizal plants such as alders are well known for their microbial symbioses that allow them to colonize harsh environments whether natural or anthropized. Although the nitrogen-fixing actinobacterium Frankia sp. is the main endophyte found in alder root nodules, other bacterial genera, whose roles remain poorly defined, inhabit this niche. In this study, we isolated a diverse panel of non-Frankia nodular endophytes (NFNE). Some NFNE were isolated from alders grown from surface-sterilized seeds and maintained in sterile conditions, suggesting these may have been seed-borne. In vitro testing of 24 NFNE revealed some possessed putative plant growth promotion traits. Their genomes were also sequenced to identify genes related to plant growth promotion traits. This study highlights the complexity of the alder nodular microbial community. It paves the way for further understanding of the biology of nodules and could help improve land reclamation practices that involve alders.
PMID: 36288604
Physiol Mol Biol Plants , IF:2.391 , 2023 Jan , V29 (1) : P11-22 doi: 10.1007/s12298-022-01275-4
Transcriptome analyses reveal the effects of mixed saline-alkali stress on indoleacetic acid and cytokinins in Malus hupehensis Rehd. leaves.
Editorial Department of Journal of Binzhou University, Binzhou University, 391 Huanghe 5th Road, Binzhou, 256603 Shandong People's Republic of China. GRID: grid.454879.3. ISNI: 0000 0004 1757 2013; Shandong Key Laboratory of Eco-Environmental Science for the Yellow River Delta, Binzhou University, 391 Huanghe 5th Road, Binzhou, 256603 Shandong People's Republic of China. GRID: grid.454879.3. ISNI: 0000 0004 1757 2013; Binzhou University, 391 Huanghe 5th Road, Binzhou, 256603 Shandong People's Republic of China. GRID: grid.454879.3. ISNI: 0000 0004 1757 2013
Saline-alkali stress is a universal abiotic stress factor limiting fruit tree cultivation worldwide. Apple (Malusxdomestica Borkh.) is one of the fruits with the largest yields worldwide. Tea crabapple (Malus hupehensis Rehd. var. pingyiensis Jiang) is a type of common apple rootstock in China. Because facultative apomixis occurs in this species, it is often used in molecular research. The present study investigated the molecular mechanism of the response of indoleacetic acid (IAA) and cytokinins [zeatin, trans-zeatin riboside (tZR), isopentenyladenine (iP), and isopentenyladenosine (iPA)] to mixed saline-alkali stress (MSAS) in tea crabapple leaves. The endogenous hormone content of tea crabapple leaves under MSAS was measured, and the expression of stress response-related genes was analyzed by RNA sequencing. The results showed that the concentration of IAA was initially higher and then lower than that in the control, whereas the concentration of zeatin, tZR, iP, and iPA was higher than that in the control. A total of 1262 differentially expressed genes were identified in the three comparison groups. Further analyses suggested that IAA and cytokinin biosynthetic genes were mostly upregulated in tea crabapple leaves, indicating that auxin and cytokinin signaling pathway regulation occurred in response to MSAS. These findings suggest that IAA and cytokinins play an important role in the response of tea crabapple to MSAS. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s12298-022-01275-4.
PMID: 36733836
Mol Biol Rep , IF:2.316 , 2023 Feb doi: 10.1007/s11033-022-08123-4
Physiological and iTRAQ-based quantitative proteomics analyses reveal the similarities and differences in stress responses between short-term boron deficiency and toxicity in wheat roots.
College of Life Sciences, Henan Agricultural University, Zhengzhou, 450002, Henan, China.; College of Life Sciences, Henan Agricultural University, Zhengzhou, 450002, Henan, China. hdy001@126.com.
BACKGROUND: Boron (B) is a trace element that is essential for normal wheat development, such as root growth. In wheat, roots are important organs that absorb nutrients and water. However, at present, there is insufficient research on the molecular mechanism underlying how short-term B stress affects wheat root growth. METHODS AND RESULTS: Here, the optimal concentration of B for wheat root growth was determined, and the proteomic profiles of roots under short-term B deficiency and toxicity were analyzed and compared by the isobaric tag for relative and absolute quantitation (iTRAQ) technique. A total of 270 differentially abundant proteins (DAPs) that accumulated in response to B deficiency and 263 DAPs that accumulated in response to B toxicity were identified. Global expression analysis revealed that ethylene, auxin, abscisic acid (ABA), and Ca(2+) signals were involved in the responses to these two stresses. Under B deficiency, DAPs related to auxin synthesis or signaling and DAPs involved in calcium signaling increased in abundance. In striking contrast, auxin and calcium signals were repressed under B toxicity. Twenty-one DAPs were detected under both conditions, including RAN1 that played a core role in the auxin and calcium signals. Overexpression of RAN1 was shown to confer plant resistance to B toxicity by activating auxin response genes, including TIR and those identified by iTRAQ in this research. Moreover, growth of the primary roots of tir mutant was significantly inhibited under B toxicity. CONCLUSION: Taken together, these results indicate that some connections were present between RAN1 and the auxin signaling pathway under B toxicity. Therefore, this research provides data for improving the understanding of the molecular mechanism underlying the response to B stress.
PMID: 36795283
Mol Biol Rep , IF:2.316 , 2023 Feb , V50 (2) : P1089-1099 doi: 10.1007/s11033-022-07999-6
Phylogeny, gene structures, and expression patterns of the auxin response factor (GhARF2) in upland cotton (Gossypium hirsutum L.).
College of Agronomy, Henan Agricultural University, Zhengzhou, 450046, China.; Postdoctoral Research Base, Henan Collaborative Innovation Center of Modern Biological Breeding, Henan Institute of Science and Technology, Xinxiang, 453003, China.; State Key Laboratory of Crop Biology, College of Agronomy, Shandong Agricultural University, Taian, 271018, China.; College of Agronomy, Henan Agricultural University, Zhengzhou, 450046, China. tangjihua1@163.com.; Postdoctoral Research Base, Henan Collaborative Innovation Center of Modern Biological Breeding, Henan Institute of Science and Technology, Xinxiang, 453003, China. wangql985@163.com.
BACKGROUND: Auxin response factors (ARFs) are a class of transcription factors that regulate the expression of auxin-responsive genes and play important functions in plant growth and development. To understand the biological functions of the auxin response factor GhARF2 gene in upland cotton, the coding sequence (CDS) of GhARF2 gene was cloned, and its protein sequence, evolutionary relationship, subcellular localization and expression pattern were analysed. METHODS: The CDS sequence of GhARF2 gene was cloned from upland cotton variety Baimian No.1, and its protein sequence was analyzed by bioinformatics method. The subcellular localization of GhARF2 protein was detected by tobacco epidermal transient transformation system, and the tissue expression and stress expression pattern of GhARF2 were analyzed by quantitative Real‑Time PCR (qRT-PCR). RESULTS: The full-length CDS of GhARF2 gene was 2583 bp, encoded 860 amino acids, and had a molecular weight and an isoelectric point of 95.46 KDa and 6.02, respectively. The GhARF2 protein had multiple phosphorylation sites, no transmembrane domain, and secondary structures dominated by random coils and alpha helix. The GhARF2 protein had 3 conserved typical domains of ARF gene family members, including the B3 DNA binding domain, the Auxin_resp domain, and the Aux/IAA domain. Phylogenetic analysis revealed that ARF2 proteins in different species were clustered in the Group A subgroup, in which GhARF2 was closely related to TcARF2 of Theobroma cacao L. (Malvaceae). The subcellular localization results showed that the GhARF2 protein was localized in the nucleus. Analysis of tissue expression pattern showed that the GhARF2 gene was expressed in all tested tissues, with the highest expression levels in sepal, followed by leaf, and the lowest expression levels in fiber. Further stress expression analysis showed that the GhARF2 gene was induced by drought, high-temperature, low-temperature and salt stress, and had different expression patterns under different stress conditions. CONCLUSION: These results established a foundation for understanding the functions of GhARF2 and breeding varieties with high-stress tolerance in cotton.
PMID: 36399242
J Basic Microbiol , IF:2.281 , 2023 Jan , V63 (1) : P17-25 doi: 10.1002/jobm.202200463
Transcriptome analysis of Armillaria gallica 012 m in response to auxin.
Key Laboratory of Chemistry in Ethnic Medicinal Resources, State Ethnic Affairs Commission and Ministry of Education, Yunnan Minzu University, Kunming, China.; Department of Chemistry, School of Chemistry and Environment, Yunnan Minzu University, Kunming, China.; Life Science College, Southwest Forestry University, Kunming, China.; Kunming Xianghao Technology Co. Ltd., Kunming, China.
Gastrodia elata is an achlorophyllous and fully mycoheterotrophic orchid which obtains carbon and other nutrients from Armillaria species in its life cycle. Many researchers suggested that plant hormones, as signing molecules, play a central role in the plant-fungi interaction. In the process of Armillaria gallica 012 m cultivation, both exogenous indole-3-acetic acid (IAA) and indole-3-butyric acid (IBA) distinctly stimulated the growth of mycelia in solid media. The differential expression genes (DEGs) of A. gallica 012 m with IAA versus blank control (BK) and IBA versus BK were investigated. The results showed that more than 80% of DEGs of the IAA group were coincident with the DEGs of the IBA group, and more than half of upregulated DEGs and most of the downregulated DEGs of the IAA group coincided with those DEGs of the IBA group. Above research implied that A. gallica 012 m could perceive IAA and IBA, and possess similar responses and signaling pathways to IAA and IBA. The overlapping differential genes of the IAA group and IBA group were analyzed by GO term, and the results showed that several DEGs identified were related to biological processes including positive regulation of the biological process and biological process. The downregulated NmrA-like and FKBP_C genes might be benefit to the growth of mycelia. Those results can explain that exiguous IAA and IBA improved the growth of A. gallica to some extent. We speculate that IAA and IBA are signaling molecules, and regulate the expression of growth-related genes of A. gallica 012 m by the same signaling pathway.
PMID: 36449692
Antonie Van Leeuwenhoek , IF:2.271 , 2023 Mar , V116 (3) : P231-242 doi: 10.1007/s10482-022-01800-1
Devosia oryzisoli sp. nov., a novel moderately halotolerant bacterium isolated from the roots of rice plants and genome mining revealed the biosynthesis potential as plant growth promoter.
Department of Life Science, Dongguk University-Seoul, 10326, Goyang, South Korea.; Department of Life Science, Dongguk University-Seoul, 10326, Goyang, South Korea. tseo@dongguk.edu.
A Gram-stain-negative, halotolerant bacterium designated as PTR5(T) was isolated from the roots of rice plants, collected in Ilsan, South Korea. Cells were, aerobic, asporogenous, motile, rod-shaped, white in color, and grew at 5-38 degrees C (optimum 30 degrees C), at pH 5.0-0-8.0 (optimum, 7.0) and tolerates up to 10% (w/v) NaCl (optimum, 0% NaCl). According to the EZbioCloud server the most closely related Devosia species to strain PTR5(T) based on 16 S rRNA gene sequence comparison are Devosia crocina (97.4%), followed by D. soli (97.2%), D. lucknowensis (96.9%) and D. marina (96.5%). The respiratory quinone was identified as Q-10. The major polar lipids were phosphatidylglycerol and diphosphatidylglycerol. C(16:0), C(18:1) omega7c 11-methyl and summed feature 8 (comprising C(18:1) omega7c/C(18:1) omega6c) constituted the main cellular fatty acids. The draft genome sequence of strain PTR5(T) was 3,689,283 bp in size. The average nucleotide identity (ANI), digital DNA-DNA hybridization (dDDH) and amino acid identity (AAI) values between strain PTR5(T) and its close relative were 72.8-76.8%, 19-20.7% and 70.3-75%, respectively. The G + C content was 63.7%. Strain PTR5(T) was able to produce siderophore and indole acetic acid (IAA) in the presence of L-tryptophan. Genes for siderophore production, auxin responsive and tryptophan biosynthesis were present in the genome of novel strain. Also, gene clusters involved in detoxification of various metal pollutants and antibiotics were also revealed in the genome of novel strain PTR5(T), this suggest that novel strain can facilitate bioremediation of heavy metals and antibiotics in contaminated areas. This study aimed to determine the detailed taxonomic position of the strain PTR5(T) using the modern polyphasic approach. On the basis of evidence presented in this study, strain PTR5(T) is considered to represent a novel species of the genus Devosia, for which the name Devosia oryzisoli sp. nov. (type strain PTR5(T) (KCTC 82691(T) = TBRC 15163(T)) is proposed.
PMID: 36525157
Plant Signal Behav , IF:2.247 , 2023 Dec , V18 (1) : P2163342 doi: 10.1080/15592324.2022.2163342
Cloning and expression study of a high-affinity nitrate transporter gene from Zea mays L.
Heilongjiang Academy of Agricultural Sciences, Harbin, Heilongjiang, China.; Key Laboratory of Saline-Alkali Vegetation Ecology Restoration, Ministry of Education, College of Life Sciences, Northeast Forestry University, Harbin, Heilongjiang, China.; Aulin College, Northeast Forestry University, Harbin, Heilongjiang, China.
A nitrate transporter gene, named B46NRT2.1, from salt-tolerant Zea mays L. B46 has been cloned. B46NRT2.1 contained the same domain belonging to the major facilitator superfamily (PLN00028). The results of the phylogenetic tree indicated that B46NRT2.1 exhibits sequence similarity and the closest relationship with those known nitrate transporters of the NRT2 family. Through RT-qPCR, we found that the expression of B46NRT2.1 mainly happens in the root and leaf. Moreover, the treatment with NaCl, Na(2)CO(3), and NaHCO(3) could significantly increase the expression of B46NRT2.1. B46NRT2.1 was located in the plasma membrane. Through the study of yeast and plant salt response brought by B46NRT2.1 overexpression, we have preliminary knowledge that the expression of B46NRT2.1 makes yeast and plants respond to salt shock. There are 10 different kinds of cis-acting regulatory elements (CRES) in the promotor sequences of B46NRT2.1 gene using the PlantCARE web server to analyze. It mainly includes hormone response, abscisic acid, salicylic acid, gibberellin, methyl jasmonate, and auxin. The B46NRT2.1 gene's co-expression network showed that it was co-expressed with a number of other genes in several biological pathways, including regulation of NO(3) long-distance transit, modulation of nitrate sensing and metabolism, nitrate assimilation, and transduction of Jasmonic acid-independent wound signal. The results of this work should serve as a good scientific foundation for further research on the functions of the NRT2 gene family in plants (inbred line B46), and this research adds to our understanding of the molecular mechanisms under salt tolerance.
PMID: 36645908
Plant Signal Behav , IF:2.247 , 2022 Dec , V17 (1) : P2096780 doi: 10.1080/15592324.2022.2096780
GIGANTEA regulates lateral root formation by modulating auxin signaling in Arabidopsis thaliana.
Department of Plant Developmental Biology, Max Planck Institute for Plant Breeding Research, Cologne, Germany.
Lateral root (LR) formation is a vital organogenetic process that determines the root architecture in plants. The number of root branches governs the degree of anchorage, efficiency of nutrients acquisition, and water uptake. The molecular pathways involved in LR formation have been extensively studied in Arabidopsis thaliana (At). A plant hormone, Auxin, is a key regulator of root development and promotes LR formation in plants. A plethora of Arabidopsis genes have been identified to regulate LR initiation, patterning, and emergence processes. Recently, the involvement of flowering time control pathways and circadian clock pathways in LR development has come to light, but the connecting link between these processes is still missing. We have established that GIGANTEA (GI), a key component of photoperiodic flowering, can regulate the formation of LRs in Arabidopsis. GI is known to be involved in red light signaling and circadian clock signaling pathways. Here, we report that over-expression of GI enhances LR formation in red light in At. Real-time PCR analysis shows that GI positively regulates the transcription of TRANSPORT INHIBITOR RESPONSE 1 (TIR1) which is an upstream component of auxin signaling. Furthermore, gi-100 mutant downregulates the LR initiation signaling gene, AUXIN RESPONSE FACTOR 7 (ARF7), and its downstream target gene, LATERAL ORGAN BOUNDARIES-DOMAIN 16 (LBD16). Hence, GI acts as a positive regulator of IAA14-ARF7-LBD16 modules during LR initiation. We have also checked the effect of GI on the expression of NAC1 and AIR3 genes which are controlled by TIR1 during LR formation. Our results show that GI induces the NAC1 transcription and its downstream gene, AIR3 expression, which leads to the enhancement of LR initiation. Taken together, our results suggest that GI controls the expression of TIR1 to govern auxin signaling during LR formation in presence of red light and GI can act as a link between circadian clock signaling, flowering time control pathways, light signaling, and lateral root development pathways.
PMID: 35822517
Plant Signal Behav , IF:2.247 , 2022 Dec , V17 (1) : P2095143 doi: 10.1080/15592324.2022.2095143
Chemically defined elicitors activate priming in tomato seedlings.
Department of Research and Development, Zero Gravity Solutions, Inc., Boca Raton, FL, USA.
Tomato (Solanum lycopersicum L.) is an important crop that possesses about 35,000 genes. The treatment of plants with elicitors or pathogen attacks causes a cascade of defense reactions. We investigated tomato responses to the BamFX(TM) solution containing Zn and Cu elicitors and report the results of comparative transcriptome analysis of tomato seeds treated with Zn and Cu elicitors. The seeds were treated with optimum concentrations of Bam-FX solutions and subjected to cold methanolic extraction methods to obtain the secondary metabolites produced within them at different time intervals post-Bam-FX treatment. The metabolite mixture was analyzed using gas chromatography-mass spectrometry (GCMS). In transcriptome sequencing, GO and KEGG analyses revealed that the majority of the DEGs in BamFx-treated tomato was associated with primary and secondary metabolism, plant hormone signal transduction, TF regulation, transport, and responses to stimuli.The secondary metabolites found in the BamFX treated tomato seedlings - Esters of Fumaric acid, Succinic acid etc. The transcript levels of most auxin transporter-encoding genes changed significantly in the BamFX-treated seedlings (e.g., Solyc01g007010.3, a RING-type E3 ubiquitin transferase). The gene Solyc07g061720.3 for Gibberellin 2-oxidase and the Phorbol-ester/DAG-type domain-containing protein (Solyc02g068680.1) associated with the intracellular signaling genes were found upregulated in the BamFx-treated seeds. The time-dependent effect of the BamFX (1:500 for 60 min) was found to be regulating Abscisic acid signaling pathway genes (Solyc09g015380.1). This study identified many candidate genes for future functional analyses and laid a theoretical foundation for an improved understanding of the molecular mechanisms involved in the BamFx treatment of tomatoes to improve stress resistance.
PMID: 35770510
Plant Signal Behav , IF:2.247 , 2022 Dec , V17 (1) : P2065432 doi: 10.1080/15592324.2022.2065432
Functional redundancy of OsPIN1 paralogous genes in regulating plant growth and development in rice.
Institute of Plant Biology, College of Life Sciences, Zhejiang University, Hangzhou, Zhejiang, China.; Agricultural Experiment Station of Zhejiang University, Hangzhou, Zhejiang, China.
The OsPIN1 paralogous genes (OsPIN1a-1d) are important for root and panicle development in rice (Oryza sativa L.). However, the specific role of OsPIN1 paralogous genes is still not clear. To understand the specific roles of PIN1 paralogs in rice, we generated pin1 triple and quadruple mutants by crossing the pin1a pin1b and pin1c pin1d double mutants which we previously created. Compared with the 7-day-old wild type, the pin1a pin1c pin1d and pin1b pin1c pin1d triple mutants showed no obvious phenotype variation except that the pin1a pin1c pin1d triple mutant had shorter primary root and shoot. The pin1a pin1b pin1c and pin1a pin1b pin1d triple mutants exhibited a series of developmental abnormalities, including shorter primary roots, longer root hairs, fewer crown roots and lateral roots, shorter and curved shoots. Furthermore, the pin1a pin1b pin1c pin1d quadruple mutant displayed more severe phenotypic defects which was lethal. In addition, the expression levels of some hormone signal transduction and crown root development related genes, such as OsIAAs, OsARFs, OsRRs, and OsCRLs, were significantly altered in the stem base of all examined pin1 multiple mutants. Taken together, our results demonstrated that the four OsPIN1 paralogous genes function redundantly in regulating rice growth and development.
PMID: 35442849
Plant Signal Behav , IF:2.247 , 2022 Dec , V17 (1) : P2031784 doi: 10.1080/15592324.2022.2031784
The epigenetic regulator ULTRAPETALA1 suppresses de novo root regeneration from Arabidopsis leaf explants.
Key Laboratory of Saline-Alkali Vegetation Ecology Restoration Ministry of Education, Northeast Forestry University, Harbin, China.; College of Life Science, Institute of Genetics, Northeast Forestry University, Harbin, China.; Lushan Botanical Garden, Chinese Academy of Sciences, Jiujiang, China.
Plants have the potency to regenerate adventitious roots from aerial organs after detachment. In Arabidopsis thaliana, de novo root regeneration (DNRR) from leaf explants is triggered by wounding signaling that rapidly induces the expression of the ETHYLENE RESPONSE FACTOR (ERF) transcription factors ERF109 and ABR1 (ERF111). In turn, the ERFs promote the expression of ASA1, an essential enzyme of auxin biosynthesis, which contributes to rooting by providing high levels of auxin near the wounding side of the leaf. Here, we show that the loss of the epigenetic regulator ULTRAPETALA1 (ULT1), which interacts with Polycomb and Trithorax Group proteins, accelerates and reinforces adventitious root formation. Expression of ERF109 and ASA1 was increased in ult1 mutants, whereas ABR1 was not significantly changed. Cultivation of explants on media with exogenous auxin equates adventitious root formation in wild-type with ult1 mutants, suggesting that ULT1 negatively regulates DNRR by suppressing auxin biosynthesis. Based on these findings, we propose that ULT1 is involved in a novel mechanism that prevents overproliferation of adventitious roots during DNRR.
PMID: 35164655
Life Sci Space Res (Amst) , IF:2.082 , 2023 Feb , V36 : P138-146 doi: 10.1016/j.lssr.2022.10.005
Comprehensive analyses of plant hormones in etiolated pea and maize seedlings grown under microgravity conditions in space: Relevance to the International Space Station experiment "Auxin Transport".
Japan Aerospace Exploration Agency, 2-1-1 Sengen, Tsukuba, Ibaraki 305-8505, Japan. Electronic address: yamazaki.chiaki@jaxa.jp.; Japan Aerospace Exploration Agency, 2-1-1 Sengen, Tsukuba, Ibaraki 305-8505, Japan. Electronic address: yamazaki.tomokazu@jaxa.jp.; Mass Spectrometry and Microscopy Unit, RIKEN Center for Sustainable Resource Science (CSRS), Suehiro-cho, Tsurumi-ku, Yokohama 230-0045, Japan. Electronic address: mikiko@riken.jp.; Mass Spectrometry and Microscopy Unit, RIKEN Center for Sustainable Resource Science (CSRS), Suehiro-cho, Tsurumi-ku, Yokohama 230-0045, Japan. Electronic address: yumiko.takebayashi@riken.jp.; Mass Spectrometry and Microscopy Unit, RIKEN Center for Sustainable Resource Science (CSRS), Suehiro-cho, Tsurumi-ku, Yokohama 230-0045, Japan; Graduate School of Bioagricultural Sciences, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8601, Japan. Electronic address: sakaki@agr.nagoya-u.ac.jp.; Graduate School of Science, Osaka Prefecture University, 1-1 Gakuen-cho, Naka-ku, Sakai, Osaka 599-8531, Japan. Electronic address: ueda-f@basil.ocn.ne.jp.; Faculty of Agriculture, Tottori University, 4-101 Koyamacho-minami, Tottori 680-8553, Japan. Electronic address: m.oka@muses.tottori-u.ac.jp.; Future Development Division, Advanced Engineering Services Co., Ltd., 1-6-1 Takezono, Tsukuba, Ibaraki 305-0032, Japan. Electronic address: kamada.motoshi@jaxa.jp.; Technology and Research Promotion Department, Japan Space Forum, Shin-Otemachi Bldg. 7F, 2-2-1 Otemachi, Chiyoda-ku, Tokyo 100-0004, Japan. Electronic address: shimazu@spacelife.tokyo.; Utilization Engineering Department, Japan Manned Space System Corporation, Space Station Test Building, Tsukuba Space Center, 2-1-1 Sengen, Tsukuba, Ibaraki 305-8505, Japan. Electronic address: kasahara.haruo@jaxa.jp.; Utilization Engineering Department, Japan Manned Space System Corporation, Space Station Test Building, Tsukuba Space Center, 2-1-1 Sengen, Tsukuba, Ibaraki 305-8505, Japan. Electronic address: sano.hiromi@jaxa.jp.; Japan Aerospace Exploration Agency, 2-1-1 Sengen, Tsukuba, Ibaraki 305-8505, Japan. Electronic address: suzuki.tomomi@jaxa.jp.; Japan Aerospace Exploration Agency, 2-1-1 Sengen, Tsukuba, Ibaraki 305-8505, Japan. Electronic address: higashibata.akira@jaxa.jp.; Faculty of Liberal Arts and Sciences, Osaka Prefecture University, 1-1 Gakuen-cho, Naka-ku, Sakai, Osaka 599-8531, Japan. Electronic address: k.miyamoto@omu.ac.jp.; Graduate School of Science, Osaka Prefecture University, 1-1 Gakuen-cho, Naka-ku, Sakai, Osaka 599-8531, Japan. Electronic address: w21913n@omu.ac.jp.
Functional relationships between endogenous levels of plant hormones in the growth and development of shoots in etiolated Alaska pea and etiolated Golden Cross Bantam maize seedlings under different gravities were investigated in the "Auxin Transport" experiment aboard the International Space Station (ISS). Comprehensive analyses of 31 species of plant hormones of pea and maize seedlings grown under microgravity (mug) in space and 1 g conditions were conducted. Principal component analysis (PCA) and a multiple regression analysis with the dataset from the plant hormone analysis of the etiolated pea seedlings grown under mug and 1 g conditions in the presence and absence of 2,3,5-triiodobenzoic acid (TIBA) revealed endogenous levels of auxin correlated positively with bending and length of epicotyls. Endogenous cytokinins correlated negatively with them. These results suggest an interaction of auxin and cytokinins in automorphogenesis and growth inhibition of etiolated Alaska pea epicotyls grown under mug conditions in space. Less polar auxin transport with reduced endogenous levels of auxin increased endogenous levels of cytokinins, resulting in changing the growth direction of epicotyls and inhibiting growth. On the other hand, almost no close relationship between endogenous plant hormone levels and growth and development in etiolated maize seedlings grown was observed under mug conditions in space, as per Schulze et al. (1992). However, endogenous levels of IAA in the seedlings grown under mug conditions in space were significantly higher than those grown on Earth, similar to the cases of polar auxin transport already reported.
PMID: 36682823
Methods Enzymol , IF:1.6 , 2023 , V680 : P35-83 doi: 10.1016/bs.mie.2022.07.034
Biochemical characterization of plant aromatic aminotransferases.
Department of Botany, University of Wisconsin-Madison, Madison, WI, United States. Electronic address: koper@wisc.edu.; Research Faculty of Agriculture, Hokkaido University, Sapporo, Japan.; Department of Botany, University of Wisconsin-Madison, Madison, WI, United States.; Department of Botany, University of Wisconsin-Madison, Madison, WI, United States. Electronic address: maeda2@wisc.edu.
Aromatic aminotransferases (Aro ATs) are pyridoxal-5-phosphate (PLP)-dependent enzymes that catalyze the transamination reactions of an aromatic amino acid (AAA) or a keto acid. Aro ATs are involved in biosynthesis or degradation of AAAs and play important functions in controlling the production of plant hormones and secondary metabolites, such as auxin, tocopherols, flavonoids, and lignin. Most Aro ATs show substrate promiscuity and can accept multiple aromatic and non-aromatic amino and keto acid substrates, which complicates and limits our understanding of their in planta functions. Considering the critical roles Aro ATs play in plant primary and secondary metabolism, it is important to accurately determine substrate specificity and kinetic properties of Aro ATs. This chapter describes various methodologies of protein expression, purification and enzymatic assays, which can be used for biochemical characterization of Aro ATs.
PMID: 36710018
PNAS Nexus , 2023 Feb , V2 (2) : Ppgad002 doi: 10.1093/pnasnexus/pgad002
Histone deacetylation regulates de novo shoot regeneration.
Department of Applied Biological Science, Faculty of Science and Technology, Tokyo University of Science, 2641 Yamazaki, Noda, Chiba 278-8510, Japan.; Plant Genomic Network Research Team, RIKEN Center for Sustainable Resource Science, 1-7-22 Suehiro, Tsurumi, Yokohama, Kanagawa 230-0045, Japan.; Plant Epigenome Regulation Laboratory, RIKEN Cluster for Pioneering Research, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan.; Department of Integrated Biosciences, Graduate School of Frontier Sciences, The University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8562, Japan.; Academic Assembly (Faculty of Science), Yamagata University, Kojirakawa, Yamagata 990-8560, Japan.; Graduate School of Life Science and Systems Engineering, Kyushu Institute of Technology, 2-4 Hibikino, Wakamatsu-ku, Kitakyushu-shi, Fukuoka 808-0196, Japan.; Department of Biological Science and Technology, Tokyo University of Science, 6-3-1 Niijuku, Katsushika-ku, Tokyo 125-8585, Japan.; School of Science and Technology, Kwansei Gakuin University, 2-1 Gakuen, Sanda, Hyogo 669-1337, Japan.; Graduate School of Life and Environmental Sciences, Kyoto Prefectural University, Shimogamo Hangi-cho, Sakyo-ku, Kyoto 60-8522, Japan.; Biotechnology Research Department, Kyoto Prefectural Agriculture Forestry and Fisheries Technology Centre, 74 Kitaina Yazuma Oji, Seika, Kyoto 619-0244, Japan.; International Research Organization for Advanced Science and Technology, Kumamoto University, 2-39-1 Kurokami, Chuo-ku, Kumamoto 860-8555, Japan.; International Research Center for Agricultural and Environmental Biology, Kumamoto University, 2-39-1 Kurokami, Chuo-ku, Kumamoto 860-855, Japan.; College of Bioscience and Biotechnology, Chubu University, 1200 Matsumoto-cho, Kasugai, Aichi 487-8501, Japan.
During de novo plant organ regeneration, auxin induction mediates the formation of a pluripotent cell mass called callus, which regenerates shoots upon cytokinin induction. However, molecular mechanisms underlying transdifferentiation remain unknown. Here, we showed that the loss of HDA19, a histone deacetylase (HDAC) family gene, suppresses shoot regeneration. Treatment with an HDAC inhibitor revealed that the activity of this gene is essential for shoot regeneration. Further, we identified target genes whose expression was regulated through HDA19-mediated histone deacetylation during shoot induction and found that ENHANCER OF SHOOT REGENERATION 1 and CUP-SHAPED COTYLEDON 2 play important roles in shoot apical meristem formation. Histones at the loci of these genes were hyperacetylated and markedly upregulated in hda19. Transient ESR1 or CUC2 overexpression impaired shoot regeneration, as observed in hda19. Therefore, HDA19 mediates direct histone deacetylation of CUC2 and ESR1 loci to prevent their overexpression at the early stages of shoot regeneration.
PMID: 36845349
MicroPubl Biol , 2023 , V2023 doi: 10.17912/micropub.biology.000708
ARF19 Condensation in the Arabidopsis Stomatal Lineage.
Department of Biology, Duke University, Durham, North Carolina 27708, USA.
The phytohormone auxin regulates nearly every aspect of plant development. Transcriptional responses to auxin are driven by the activities of the AUXIN RESPONSE FACTOR family of transcription factors. ARF19 (AT1G19220) is critical in the auxin signaling pathway and has previously been shown to undergo protein condensation to tune auxin responses in the root. However, ARF19 condensation dynamics in other organs has not yet been described. In the Arabidopsis stomatal lineage, we found that ARF19 cytoplasmic condensates are enriched in guard cells and pavement cells, terminally differentiated cells in the leaf epidermis. This result is consistent with previous studies showing ARF19 condensation in mature root tissues. Our data reveal that the sequestration of ARF19 into cytoplasmic condensation in differentiated leaf epidermal cells is similar to root-specific condensation patterns.
PMID: 36814574
Microbiol Resour Announc , 2023 Feb , V12 (2) : Pe0104622 doi: 10.1128/mra.01046-22
Draft Genome Sequences of Four Plant Growth-Promoting Rhizobacteria Isolated from Saffron (Crocus sativus L.) Rhizosphere in Morocco.
Laboratory of Microbiology and Molecular Biology, Faculty of Sciences, Mohammed V University in Rabat, Rabat, Morocco.; Biotechnology Laboratory, Bioinova Research Center, Rabat Medical and Pharmacy School, Mohammed V University in Rabat, Rabat, Morocco.
We report the draft genome sequences of plant growth-promoting Rahnella perminowiae strain S11P1, Variovorax sp. strain S12S4, and Pseudomonas sp. strains S11A4 and S11P7, which were isolated from saffron (Crocus sativus L.) rhizosphere. Several genes were predicted to be involved in auxin production, phosphate solubilization, and other specialized functions in plant growth and defense.
PMID: 36633434
Cell Regen , 2023 Jan , V12 (1) : P1 doi: 10.1186/s13619-022-00140-9
WOX11: the founder of plant organ regeneration.
National Key Laboratory of Plant Molecular Genetics, CAS Center for Excellence in Molecular Plant Sciences, Institute of Plant Physiology and Ecology, Chinese Academy of Sciences, 300 Fenglin Road, Shanghai, 200032, China.; University of Chinese Academy of Sciences, 19A Yuquan Road, Beijing, 100049, China.; National Key Laboratory of Plant Molecular Genetics, CAS Center for Excellence in Molecular Plant Sciences, Institute of Plant Physiology and Ecology, Chinese Academy of Sciences, 300 Fenglin Road, Shanghai, 200032, China. xulin@cemps.ac.cn.
De novo organ regeneration is the process in which adventitious roots or shoots regenerate from detached or wounded organs. De novo organ regeneration can occur either in natural conditions, e.g. adventitious root regeneration from the wounded sites of detached leaves or stems, or in in-vitro tissue culture, e.g. organ regeneration from callus. In this review, we summarize recent advances in research on the molecular mechanism of de novo organ regeneration, focusing on the role of the WUSCHEL-RELATED HOMEOBOX11 (WOX11) gene in the model plant Arabidopsis thaliana. WOX11 is a direct target of the auxin signaling pathway, and it is expressed in, and regulates the establishment of, the founder cell during de novo root regeneration and callus formation. WOX11 activates the expression of its target genes to initiate root and callus primordia. Therefore, WOX11 links upstream auxin signaling to downstream cell fate transition during regeneration. We also discuss the role of WOX11 in diverse species and its evolution in plants.
PMID: 36596978
Methods Mol Biol , 2023 , V2581 : P43-56 doi: 10.1007/978-1-0716-2784-6_4
An In vitro Assay to Recapitulate Hormone-Triggered and SCF-Mediated Protein Ubiquitylation.
Molecular Signal Processing Department, Leibniz Institute of Plant Biochemistry (IPB), Halle (Saale), Germany.; Molecular Signal Processing Department, Leibniz Institute of Plant Biochemistry (IPB), Halle (Saale), Germany. LuzIrina.Calderon@ipb-halle.de.; KWS Gateway Research Center, LLC, BRDG Park at the Danforth Plant Science Center, St. Louis, MO, USA. LuzIrina.Calderon@ipb-halle.de.
Signaling proteins trigger a sequence of molecular switches in the cell, which permit development, growth, and rapid adaptation to changing environmental conditions. SCF-type E3 ubiquitin ligases recognize signaling proteins prompting changes in their fate, one of these being ubiquitylation followed by degradation by the proteasome. SCFs together with their ubiquitylation targets (substrates) often serve as phytohormone receptors, responding and/or assembling in response to fluctuating intracellular hormone concentrations. Tracing and understanding phytohormone perception and SCF-mediated ubiquitylation of proteins could provide powerful clues on the molecular mechanisms utilized for plant adaptation. Here, we describe an adaptable in vitro system that uses recombinant proteins and enables the study of hormone-triggered SCF-substrate interaction and the dynamics of protein ubiquitylation. This system can serve to predict the requirements for protein recognition and to understand how phytohormone levels have the power to control protein fate.
PMID: 36413309