Annu Rev Plant Biol , IF:26.379 , 2023 May , V74 : P453-479 doi: 10.1146/annurev-arplant-070722-015329
Plant Hormone Transport and Localization: Signaling Molecules on the Move.
School of Plant Sciences and Food Security, Tel Aviv University, Tel Aviv, Israel; email: eilonsh@tauex.tau.ac.il.; Current affiliation: College of Advanced Agricultural Sciences, University of Chinese Academy of Sciences, Beijing, China; email: zhangyuqin@ucas.ac.cn.
Plant hormones are a group of small signaling molecules produced by plants at very low concentrations that have the ability to move and function at distal sites. Hormone homeostasis is critical to balance plant growth and development and is regulated at multiple levels, including hormone biosynthesis, catabolism, perception, and transduction. In addition, plants move hormones over short and long distances to regulate various developmental processes and responses to environmental factors. Transporters coordinate these movements, resulting in hormone maxima, gradients, and cellular and subcellular sinks. Here, we summarize the current knowledge of most of the characterized plant hormone transporters with respect to biochemical, physiological, and developmental activities. We further discuss the subcellular localizations of transporters, their substrate specificities, and the need for multiple transporters for the same hormone in the context of plant growth and development.
PMID: 36889002
Annu Rev Plant Biol , IF:26.379 , 2023 May , V74 : P387-413 doi: 10.1146/annurev-arplant-102720-033523
Decoding the Auxin Matrix: Auxin Biology Through the Eye of the Computer.
Laboratoire Reproduction et Developpement des Plantes, Universite de Lyon and ENS de Lyon, CNRS, INRAE, Lyon, France; email: raquel.martin@ens-lyon.fr, teva.vernoux@ens-lyon.fr.
The plant hormone auxin is certainly the most studied developmental regulator in plants. The many functions of auxin during development, from the embryo to the root and shoot construction, are mediated by an ever-growing collection of molecular regulators, with an overwhelming degree of both ubiquity and complexity that we are still far from fully understanding and that biological experiments alone cannot grasp. In this review, we discuss how bioinformatics and computational modeling approaches have helped in recent years to explore this complexity and to push the frontiers of our understanding of auxin biology. We focus on how analysis of massive amounts of genomic data and construction of computational models to simulate auxin-regulated processes at different scales have complemented wet experiments to increase the understanding of how auxin acts in the nucleus to regulate transcription and how auxin movement between cells regulates development at the tissular scale.
PMID: 36608348
Trends Plant Sci , IF:18.313 , 2023 May doi: 10.1016/j.tplants.2023.05.003
A complex signaling trio in seed germination: Auxin-JA-ABA.
Institute of Biology, Biotechnology and Environmental Protection, Faculty of Natural Sciences, University of Silesia in Katowice, Jagiellonska 28, 40-032 Katowice, Poland.; Institute of Biology, Biotechnology and Environmental Protection, Faculty of Natural Sciences, University of Silesia in Katowice, Jagiellonska 28, 40-032 Katowice, Poland. Electronic address: agata.daszkowska@us.edu.pl.
Recently. Mei et al. discovered the molecular mechanism behind the synergistic action of auxins and jasmonates in enhancing the role of abscisic acid (ABA) in seed germination. They found that JASMONATE-ZIM DOMAIN (JAZ) proteins interact with AUXIN RESPONSE FACTOR (ARF)-16 to mediate auxin-jasmonic acid (JA) crosstalk. Furthermore, they revealed that ARF16 interacts with ABSCISIC ACID INSENSITIVE (ABI)-5 and positively modulates ABA responses at seed germination.
PMID: 37208202
Trends Plant Sci , IF:18.313 , 2023 Jun , V28 (6) : P611-613 doi: 10.1016/j.tplants.2023.03.016
Endoreplication controls cell size via mechanochemical signaling.
Plant & Crop Sciences, School of Biosciences, University of Nottingham, Nottingham, LE12 5RD, UK. Electronic address: rahul.bhosale@nottingham.ac.uk.; Integrated Molecular Plant Physiology Research (IMPRES), Biology Department, University of Antwerp, 2020 Antwerp, Belgium; Plant Biochemistry & Biotechnology Lab, Department of Agriculture, Hellenic Mediterranean University, Stavromenos PC 71410, Heraklion, Crete, Greece. Electronic address: kris.vissenberg@uantwerpen.be.
During hypocotyl development, an asymmetric auxin gradient causes differential cell elongation, leading to tissue bending and apical hook formation. Recently, Ma et al. identified a molecular pathway that links auxin with endoreplication and cell size through cell wall integrity sensing, cell wall remodeling, and regulation of cell wall stiffness.
PMID: 36997439
Trends Plant Sci , IF:18.313 , 2023 Jun , V28 (6) : P620-622 doi: 10.1016/j.tplants.2023.03.002
Biomolecular condensation: a new player in auxin signaling.
Institute of Biology, University of Graz, Schubertstrasse 51, 8010 Graz, Austria. Electronic address: alicja.gorska@uni-graz.at.; Institute of Biology, University of Graz, Schubertstrasse 51, 8010 Graz, Austria.
Biomolecular condensates are increasingly being recognized as a fundamental mechanism for the organization of the intracellular space. Powers et al. and Jing et al. have demonstrated that a cytoplasmic condensation of AUXIN RESPONSE FACTOR (ARF) transcription factors restrains auxin responses, acting as an additional regulatory layer in the auxin-mediated control of plant development.
PMID: 36959045
Trends Plant Sci , IF:18.313 , 2023 Apr , V28 (4) : P447-459 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
Nat Plants , IF:15.793 , 2023 May doi: 10.1038/s41477-023-01406-z
Uncovering the transcriptional regulatory network involved in boosting wheat regeneration and transformation.
Key Laboratory of Plant Cell and Chromosome Engineering, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, China.; National Key Laboratory of Wheat Improvement, College of Life Sciences, Shandong Agricultural University, Tai'an, China.; University of Chinese Academy of Sciences, Beijing, China.; Nanjing Agricultural University, Nanjing, China.; National Key Laboratory of Wheat Improvement, College of Life Sciences, Shandong Agricultural University, Tai'an, China. zhangxs@sdau.edu.cn.; Key Laboratory of Plant Cell and Chromosome Engineering, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, China. jxiao@genetics.ac.cn.; University of Chinese Academy of Sciences, Beijing, China. jxiao@genetics.ac.cn.; CAS-JIC Centre of Excellence for Plant and Microbial Science (CEPAMS), Institute of Genetics and Developmental Biology, CAS, Beijing, China. jxiao@genetics.ac.cn.
Genetic transformation is important for gene functional study and crop improvement. However, it is less effective in wheat. Here we employed a multi-omic analysis strategy to uncover the transcriptional regulatory network (TRN) responsible for wheat regeneration. RNA-seq, ATAC-seq and CUT&Tag techniques were utilized to profile the transcriptional and chromatin dynamics during early regeneration from the scutellum of immature embryos in the wheat variety Fielder. Our results demonstrate that the sequential expression of genes mediating cell fate transition during regeneration is induced by auxin, in coordination with changes in chromatin accessibility, H3K27me3 and H3K4me3 status. The built-up TRN driving wheat regeneration was found to be dominated by 446 key transcription factors (TFs). Further comparisons between wheat and Arabidopsis revealed distinct patterns of DNA binding with one finger (DOF) TFs in the two species. Experimental validations highlighted TaDOF5.6 (TraesCS6A02G274000) and TaDOF3.4 (TraesCS2B02G592600) as potential enhancers of transformation efficiency in different wheat varieties.
PMID: 37142750
Nat Plants , IF:15.793 , 2023 May , V9 (5) : P706-719 doi: 10.1038/s41477-023-01396-y
Four class A AUXIN RESPONSE FACTORs promote tomato fruit growth despite suppressing fruit set.
Department of Biology, Duke University, Durham, NC, USA.; School of Grassland Science, Beijing Forestry University, Beijing, P. R. China.; Department of Biology, Duke University, Durham, NC, USA. tps@duke.edu.
In flowering plants, auxin produced in seeds after fertilization promotes fruit initiation. The application of auxin to unpollinated ovaries can also induce parthenocarpy (seedless fruit production). Previous studies have shown that auxin signalling components SlIAA9 and SlARF7 (a class A AUXIN RESPONSE FACTOR (ARF)) are key repressors of fruit initiation in tomato (Solanum lycopersicum). A similar repressive role of class A ARFs in fruit set has also been observed in other plant species. However, evidence is lacking for a role of any class A ARF in promoting fruit development as predicted in the current auxin signalling model. Here we generated higher-order tomato mutants of four class A SlARFs (SlARF5, SlARF7, SlARF8A and SlARF8B) and uncovered their precise combinatorial roles that lead to suppressing and promoting fruit development. All four class A SlARFs together with SlIAA9 inhibited fruit initiation but promoted subsequent fruit growth. Transgenic tomato lines expressing truncated SlARF8A/8B lacking the IAA9-interacting PB1 domain displayed strong parthenocarpy, further confirming the promoting role of SlARF8A/8B in fruit growth. Altering the doses of these four SlARFs led to biphasic fruit growth responses, showing their versatile dual roles as both negative and positive regulators. RNA-seq and chromatin immunoprecipitation-quantitative PCR analyses further identified SlARF8A/8B target genes, including those encoding MADS-BOX transcription factors (AG1, MADS2 and AGL6) that are key repressors of fruit set. These results support the idea that SlIAA9/SlARFs directly regulate the transcription of these MADS-BOX genes to inhibit fruit set. Our study reveals the previously unknown dual function of four class A SlARFs in tomato fruit development and illuminates the complex combinatorial effects of multiple ARFs in controlling auxin-mediated fruit set and fruit growth.
PMID: 37037878
Nat Plants , IF:15.793 , 2023 Apr , V9 (4) : P631-644 doi: 10.1038/s41477-023-01360-w
Gibberellins promote polar auxin transport to regulate stem cell fate decisions in cambium.
Organismal and Evolutionary Biology Research Programme, Faculty of Biological and Environmental Sciences and Viikki Plant Science Centre, University of Helsinki, Helsinki, Finland.; Institute of Biotechnology, HiLIFE, University of Helsinki, Helsinki, Finland.; European Commission, Joint Research Centre, Geel, Belgium.; Department of Plant Science and Landscape Architecture, University of Maryland, College Park, MD, USA.; Organismal and Evolutionary Biology Research Programme, Faculty of Biological and Environmental Sciences and Viikki Plant Science Centre, University of Helsinki, Helsinki, Finland. AriPekka.Mahonen@helsinki.fi.; Institute of Biotechnology, HiLIFE, University of Helsinki, Helsinki, Finland. AriPekka.Mahonen@helsinki.fi.
Vascular cambium contains bifacial stem cells, which produce secondary xylem to one side and secondary phloem to the other. However, how these fate decisions are regulated is unknown. Here we show that the positioning of an auxin signalling maximum within the cambium determines the fate of stem cell daughters. The position is modulated by gibberellin-regulated, PIN1-dependent polar auxin transport. Gibberellin treatment broadens auxin maximum from the xylem side of the cambium towards the phloem. As a result, xylem-side stem cell daughter preferentially differentiates into xylem, while phloem-side daughter retains stem cell identity. Occasionally, this broadening leads to direct specification of both daughters as xylem, and consequently, adjacent phloem-identity cell reverts to being stem cell. Conversely, reduced gibberellin levels favour specification of phloem-side stem cell daughter as phloem. Together, our data provide a mechanism by which gibberellin regulates the ratio of xylem and phloem production.
PMID: 36997686
EMBO J , IF:11.598 , 2023 Apr : Pe111926 doi: 10.15252/embj.2022111926
Auxin-dependent regulation of cell division rates governs root thermomorphogenesis.
Institute of Agricultural and Nutritional Sciences, Martin Luther University Halle-Wittenberg, Halle (Saale), Germany.; Department of Biology, Institute of Molecular Plant Biology, ETH Zurich, Zurich, Switzerland.; Department of Cell and Metabolic Biology, Leibniz Institute of Plant Biochemistry, Halle (Saale), Germany.; Max Planck Institute for Plant Breeding Research, Cologne, Germany.
Roots are highly plastic organs enabling plants to adapt to a changing below-ground environment. In addition to abiotic factors like nutrients or mechanical resistance, plant roots also respond to temperature variation. Below the heat stress threshold, Arabidopsis thaliana seedlings react to elevated temperature by promoting primary root growth, possibly to reach deeper soil regions with potentially better water saturation. While above-ground thermomorphogenesis is enabled by thermo-sensitive cell elongation, it was unknown how temperature modulates root growth. We here show that roots are able to sense and respond to elevated temperature independently of shoot-derived signals. This response is mediated by a yet unknown root thermosensor that employs auxin as a messenger to relay temperature signals to the cell cycle. Growth promotion is achieved primarily by increasing cell division rates in the root apical meristem, depending on de novo local auxin biosynthesis and temperature-sensitive organization of the polar auxin transport system. Hence, the primary cellular target of elevated ambient temperature differs fundamentally between root and shoot tissues, while the messenger auxin remains the same.
PMID: 37071525
EMBO J , IF:11.598 , 2023 May , V42 (10) : Pe111273 doi: 10.15252/embj.2022111273
TOR acts as a metabolic gatekeeper for auxin-dependent lateral root initiation in Arabidopsis thaliana.
Center for Organismal Studies, Heidelberg University, Heidelberg, Germany.; Institut de Biologie Moleculaire des Plantes (IBMP), UPR CNRS 2357, Strasbourg, France.; Max Planck Institute of Molecular Plant Physiology, Potsdam, Germany.; Centre for Research in Agricultural Genomics, Barcelona, Spain.; Environmental Research Institute, University College Cork, Cork, Ireland.
Plant organogenesis requires matching the available metabolic resources to developmental programs. In Arabidopsis, the root system is determined by primary root-derived lateral roots (LRs), and adventitious roots (ARs) formed from non-root organs. Lateral root formation entails the auxin-dependent activation of transcription factors ARF7, ARF19, and LBD16. Adventitious root formation relies on LBD16 activation by auxin and WOX11. The allocation of shoot-derived sugar to the roots influences branching, but how its availability is sensed for LRs formation remains unknown. We combine metabolic profiling with cell-specific interference to show that LRs switch to glycolysis and consume carbohydrates. The target-of-rapamycin (TOR) kinase is activated in the lateral root domain. Interfering with TOR kinase blocks LR initiation while promoting AR formation. The target-of-rapamycin inhibition marginally affects the auxin-induced transcriptional response of the pericycle but attenuates the translation of ARF19, ARF7, and LBD16. TOR inhibition induces WOX11 transcription in these cells, yet no root branching occurs as TOR controls LBD16 translation. TOR is a central gatekeeper for root branching that integrates local auxin-dependent pathways with systemic metabolic signals, modulating the translation of auxin-induced genes.
PMID: 37021425
Plant Cell , IF:11.277 , 2023 May doi: 10.1093/plcell/koad130
The transcriptional hub SHORT INTERNODES1 integrates hormone signals to orchestrate rice growth and development.
State Key Laboratory of Crop Genetics & Germplasm Enhancement and Utilization, Jiangsu Plant Gene Engineering Research Center, Nanjing Agricultural University, Nanjing 210095, China.; State Key Laboratory of Crop Gene Resources and Breeding, Institute of Crop Sciences, Chinese Academy of Agricultural Sciences, Beijing 100081, China.
Plants have evolved sophisticated mechanisms to coordinate their growth and stress responses via integrating various phytohormone signaling pathways. However, the precise molecular mechanisms orchestrating integration of the phytohormone signaling pathways remain largely obscure. In this study, we found that the rice (Oryza sativa) short internodes1 (shi1) mutant exhibits typical auxin-deficient root development and gravitropic response, brassinosteroid (BR)-deficient plant architecture and grain size as well as enhanced abscisic acid (ABA)-mediated drought tolerance. Additionally, we found that the shi1 mutant is also hyposensitive to auxin and BR treatment but hypersensitive to ABA. Further, we showed that OsSHI1 promotes the biosynthesis of auxin and BR by activating the expression of OsYUCCAs and D11, meanwhile dampens ABA signaling by inducing the expression of OsNAC2, which encodes a repressor of ABA signaling. Furthermore, we demonstrated that three classes of transcription factors, AUXIN RESPONSE FACTOR 19 (OsARF19), LEAF AND TILLER ANGLE INCREASED CONTROLLER (LIC), OsZIP26 and OsZIP86, directly bind to the promoter of OsSHI1 and regulate its expression in response to auxin, BR and ABA, respectively. Collectively, our results unravel an OsSHI1-centered transcriptional regulatory hub that orchestrates the integration and self-feedback regulation of multiple phytohormone signaling pathways to coordinate plant growth and stress adaptation.
PMID: 37195873
Plant Cell , IF:11.277 , 2023 May doi: 10.1093/plcell/koad125
SHORT ROOT and INDETERMINATE DOMAIN family members govern PIN-FORMED expression to regulate minor vein differentiation in rice.
Biotechnology Research Institute (BRI), Chinese Academy of Agricultural Sciences (CAAS), Beijing, China.; Joint Laboratory for Photosynthesis Enhancement and C4 Rice Development, BRI, CAAS, Beijing, China.; International Rice Research Institute, Los Banos, Philippines.; Department of Animal and Plant Sciences, University of Sheffield, UK.
C3 and C4 grasses directly and indirectly provide the vast majority of calories to the human diet, yet our understanding of the molecular mechanisms driving photosynthetic productivity in grasses is largely unexplored. Ground meristem cells divide to form mesophyll or vascular initial cells early in leaf development in C3 and C4 grasses. Here we define a genetic circuit composed of SHR (SHORT ROOT), IDD (INDETERMINATE DOMAIN), and PIN (PIN-FORMED) family members that specifies vascular identify and ground cell proliferation in leaves of both C3 and C4 grasses. Ectopic expression and loss-of-function mutant studies of SHR paralogs in the C3 plant Oryza sativa (rice) and the C4 plant Setaria viridis (green millet) revealed the roles of these genes in both minor vein formation and ground cell differentiation. Genetic and in vitro studies further suggested that SHR regulates this process through its interactions with IDD12 and 13. We also revealed direct interactions of these IDD proteins with a putative regulatory element within the auxin transporter gene PIN5c. Collectively, these findings indicate that a SHR-IDD regulatory circuit mediates auxin transport by negatively regulating PIN expression to modulate minor vein patterning in the grasses.
PMID: 37154077
Proc Natl Acad Sci U S A , IF:11.205 , 2023 May , V120 (19) : Pe2218503120 doi: 10.1073/pnas.2218503120
Dual regulations of cell cycle regulator DPa by auxin in Arabidopsis root distal stem cell maintenance.
The Key Laboratory of Plant Development and Environmental Adaptation Biology, Ministry of Education, School of Life Sciences, Shandong University, 266237 Qingdao, Shandong, China.; Haixia Institute of Science and Technology, College of Life Sciences, Fujian Agriculture and Forestry University, 350002 Fuzhou, Fujian, China.
The plant hormone auxin plays a key role to maintain root stem cell identity which is essential for root development. However, the molecular mechanism by which auxin regulates root distal stem cell (DSC) identity is not well understood. In this study, we revealed that the cell cycle factor DPa is a vital regulator in the maintenance of root DSC identity through multiple auxin signaling cascades. On the one hand, auxin positively regulates the transcription of DPa via AUXIN RESPONSE FACTOR 7 and ARF19. On the other hand, auxin enhances the protein stability of DPa through MITOGEN-ACTIVATED PROTEIN KINASE 3 (MPK3)/MPK6-mediated phosphorylation. Consistently, mutation of the identified three threonine residues (Thr(10), Thr(25), and Thr(227)) of DPa to nonphosphorylated form alanine (DPa(3A)) highly decreased the phosphorylation level of DPa, which decreased its protein stability and affected the maintenance of root DSC identity. Taken together, this study provides insight into the molecular mechanism of how auxin regulates root distal stem cell identity through the dual regulations of DPa at both transcriptional and posttranslational levels.
PMID: 37126711
Proc Natl Acad Sci U S A , IF:11.205 , 2023 Apr , V120 (15) : Pe2301054120 doi: 10.1073/pnas.2301054120
Plant microbiota controls an alternative root branching regulatory mechanism in plants.
School of Biosciences, University of Nottingham, LE12 5RD, United Kingdom.; Center for Genomics Sciences, Universidad Nacional Autonoma de Mexico, 04510 Mexico City, Mexico.; Future Food Beacon of Excellence, University of Nottingham, LE12 5RD, United Kingdom.; Division of Crop Biotechnics, Department of Biosystems, KU Leuven, 3001 Leuven, Belgium.; Leuven Plant Institute, KU Leuven, 3001 Leuven, Belgium.
The establishment of beneficial interactions with microbes has helped plants to modulate root branching plasticity in response to environmental cues. However, how the plant microbiota harmonizes with plant roots to control their branching is unknown. Here, we show that the plant microbiota influences root branching in the model plant Arabidopsis thaliana. We define that the microbiota's ability to control some stages in root branching can be independent of the phytohormone auxin that directs lateral root development under axenic conditions. In addition, we revealed a microbiota-driven mechanism controlling lateral root development that requires the induction of ethylene response pathways. We show that the microbial effects on root branching can be relevant for plant responses to environmental stresses. Thus, we discovered a microbiota-driven regulatory pathway controlling root branching plasticity that could contribute to plant adaptation to different ecosystems.
PMID: 37011213
Curr Biol , IF:10.834 , 2023 May doi: 10.1016/j.cub.2023.04.061
Photosynthetic sucrose drives the lateral root clock in Arabidopsis seedlings.
Department of Molecular Plant Physiology, Faculty of Biology, University of Freiburg, Schanzlestr. 1, 79104 Freiburg, Germany. Electronic address: stefan.kircher@biologie.uni-freiburg.de.; Department of Molecular Plant Physiology, Faculty of Biology, University of Freiburg, Schanzlestr. 1, 79104 Freiburg, Germany. Electronic address: peter.schopfer@biologie.uni-freiburg.de.
The development of plant roots is subject to control by light. Here, we show that, similar to monotonous root elongation, the periodic induction of lateral roots (LRs) depends on the activation by light of photomorphogenic and photosynthetic photoreceptors in the shoot in a hierarchical order. The prevailing belief is that the plant hormone auxin serves as a mobile signal transmitter, responsible for interorgan communication, including light-controlled shoot-to-root connections. Alternatively, it has been proposed that the transcription factor HY5 assumes the role as a mobile shoot-to-root signal transmitter. Here, we provide evidence that photosynthetic sucrose produced in the shoot acts as the long-distance signal carrier regulating the local, tryptophan-based biosynthesis of auxin in the LR generation zone of the primary root tip, where the LR clock controls the pace of LR initiation in an auxin-tunable manner. Synchronization of LR formation with primary root elongation allows the adjustment of overall root growth to the photosynthetic performance of the shoot and the maintenance of a constant LR density during light-dark changes in a variable light environment.
PMID: 37207646
Curr Biol , IF:10.834 , 2023 May , V33 (10) : P2008-2023.e8 doi: 10.1016/j.cub.2023.04.029
An LRR receptor kinase controls ABC transporter substrate preferences during plant growth-defense decisions.
Department of Biology, University of Fribourg, 1700 Fribourg, Switzerland.; College of Life Sciences, Ritsumeikan University, Shiga 525-8577, Japan.; Zentrum fur Molekularbiologie der Pflanzen, Pflanzenphysiologie, Universitat Tubingen, Auf der Morgenstelle 32, 72076 Tubingen, Germany.; Department of Biology, ETH Zurich, Universitatstrasse 2, 8092 Zurich, Switzerland.; Department of Plant Molecular Physiology, Institute of Bioorganic Chemistry, Polish Academy of Sciences, Z. Noskowskiego 12/14, 61-704 Poznan, Poland; NanoBioMedical Centre, Adam Mickiewicz University, Wszechnicy Piastowskiej 3, 61-614 Poznan, Poland.; Department Molecular Signal Processing, Leibniz Institute of Plant Biochemistry, Weinberg 3, 06120 Halle (Saale), Germany.; Department Biochemistry of Plant Interactions, Leibniz Institute of Plant Biochemistry, Weinberg 3, 06120 Halle (Saale), Germany.; Mendel Centre for Plant Genomics and Proteomics Masaryk University, CEITEC MU Kamenice 5, Building A26, 625 00 Brno, Czech Republic.; Department of Plant Molecular Physiology, Institute of Bioorganic Chemistry, Polish Academy of Sciences, Z. Noskowskiego 12/14, 61-704 Poznan, Poland; Department of Biochemistry and Biotechnology, Poznan University of Life Sciences, Dojazd 11, 60-632 Poznan, Poland.; Department of Biology, University of Fribourg, 1700 Fribourg, Switzerland. Electronic address: markus.geisler@unifr.ch.
The exporter of the auxin precursor indole-3-butyric acid (IBA), ABCG36/PDR8/PEN3, from the model plant Arabidopsis has recently been proposed to also function in the transport of the phytoalexin camalexin. Based on these bonafide substrates, it has been suggested that ABCG36 functions at the interface between growth and defense. Here, we provide evidence that ABCG36 catalyzes the direct, ATP-dependent export of camalexin across the plasma membrane. We identify the leucine-rich repeat receptor kinase, QIAN SHOU KINASE1 (QSK1), as a functional kinase that physically interacts with and phosphorylates ABCG36. Phosphorylation of ABCG36 by QSK1 unilaterally represses IBA export, allowing camalexin export by ABCG36 conferring pathogen resistance. As a consequence, phospho-dead mutants of ABCG36, as well as qsk1 and abcg36 alleles, are hypersensitive to infection with the root pathogen Fusarium oxysporum, caused by elevated fungal progression. Our findings indicate a direct regulatory circuit between a receptor kinase and an ABC transporter that functions to control transporter substrate preference during plant growth and defense balance decisions.
PMID: 37146609
J Hazard Mater , IF:10.588 , 2023 Aug , V455 : P131637 doi: 10.1016/j.jhazmat.2023.131637
Indole-3-acetic acid and zinc synergistically mitigate positively charged nanoplastic-induced damage in rice.
Key laboratory of Plant Resource Conservation and Germplasm Innovation in Mountainous Region (Ministry of Education), College of Life Sciences/Institute of Agro-bioengineering, Guizhou University, Guiyang 550025, PR China.; Hainan Institute, Zhejiang University, Yazhou Bay Science and Technology City, Sanya 572025, PR China; National Key Laboratory of Rice Biology, The Advanced Seed Institute, Zhejiang University, Hangzhou 310058, PR China.; National Key Laboratory of Rice Biology, The Advanced Seed Institute, Zhejiang University, Hangzhou 310058, PR China.; Institute of Nuclear Agricultural Sciences, Zhejiang University, Hangzhou 310058, PR China. Electronic address: zhen.yang@zju.edu.cn.; Hainan Institute, Zhejiang University, Yazhou Bay Science and Technology City, Sanya 572025, PR China. Electronic address: mengjiang@zju.edu.cn.
Recent research has shown that polystyrene nanoplastics (PS-NPs) can inhibit plant growth and the development of crops, such as rice. In this study, we aimed to investigate the effects of PS-NPs of different particle sizes (80 nm, 200 nm, and 2 microm) and charges (negative, neutral, and positive) on rice growth, and to explore the underlying mechanisms and potential strategies for mitigating their impacts. Two-week-old rice plants were planted in a standard (1/2) Murashige-Skoog liquid medium holding 50 mg/L of different particle sizes and/or charged PS-NPs for 10 days, and the liquid medium without PS-NPs was used as control. The results showed that positively charged PS-NPs (80 nm PS-NH(2)) had the greatest impact on plant growth and greatly reduced the dry biomass, root length, and plant height of rice by 41.04%, 46.34%, and 37.45%, respectively. The positively charged NPs with a size of 80 nm significantly decreased the zinc (Zn) and indole-3-acetic acid (IAA, auxin) contents by 29.54% and 48.00% in roots, and 31.15% and 64.30% in leaves, respectively, and down-regulated the relative expression level of rice IAA response and biosynthesis genes. Moreover, Zn and/or IAA supplements significantly alleviated the adverse effects of 80 nm PS-NH(2) on rice plant growth. Exogenous Zn and/or IAA increased seedlings' growth, decreased PS-NPs distribution, maintained redox homeostasis, and improved tetrapyrrole biosynthesis in rice treated with 80 nm PS-NH(2). Our findings suggest that Zn and IAA synergistically alleviate positively charged NP-induced damage in rice.
PMID: 37210880
J Hazard Mater , IF:10.588 , 2023 Jun , V452 : P131226 doi: 10.1016/j.jhazmat.2023.131226
Tryptophan pretreatment adjusts transcriptome and metabolome profiles to alleviate cadmium toxicity in Arabidopsis.
Beijing Key Laboratory of Plant Gene Resources and Biotechnology for Carbon Reduction and Environmental Improvement and College of Life Sciences, Capital Normal University, Beijing 100048, China.; Beijing Key Laboratory of Plant Gene Resources and Biotechnology for Carbon Reduction and Environmental Improvement and College of Life Sciences, Capital Normal University, Beijing 100048, China. Electronic address: qixiaoting@cnu.edu.cn.
Cadmium (Cd) is highly toxic to all organisms including plants, and recently tryptophan (Trp) pretreatment of plant seedlings is shown to improve Cd tolerance. But the underlying mechanism remains largely unknown. In this study, we used Arabidopsis (Arabidopsis thaliana) to determine the physiological relevance of Trp pretreatment in alleviating Cd toxicity in plants and explore its molecular mechanism with a focus on the metabolic pathways. The results showed that Trp pretreatment maintained the biomass and root lengths, relieved Cd-induced lipid peroxidation, and reduced Cd transport to the shoots, and eventually improved the response against Cd in Arabidopsis seedlings. The integrative analyses of the transcriptome and metabolome further revealed that Trp pretreatment alleviated Cd toxicity not only through a known mechanism of producing a major auxin indole-3-acetic acid and maintaining its levels, but also through two previously unrecognized mechanisms: increasing the area and strength of cell walls by promoting lignification to further reduce Cd entry, and fine-tuning Cd detoxification products derived from sulfur-containing amino acid metabolism. Our findings thereby provide deep mechanical insights into how Trp alleviates Cd toxicity in plants.
PMID: 36934628
New Phytol , IF:10.151 , 2023 May doi: 10.1111/nph.18988
SlMYB99-mediated auxin and abscisic acid antagonistically regulate ascorbic acids biosynthesis in tomato.
Key Laboratory of Plant Hormones and Development Regulation of Chongqing, School of Life Sciences, Chongqing University, Chongqing, 400044, China.
Ascorbic acid (AsA) is a water-soluble antioxidant that plays important roles in plant development and human health. Understanding the regulatory mechanism underlying AsA biosynthesis is imperative to the development of high AsA plants. In this study, we reveal that the auxin response factor SlARF4 transcriptionally inhibits SlMYB99, which subsequently modulates AsA accumulation via transcriptional activation of AsA biosynthesis genes GPP, GLDH, and DHAR. The auxin-dependent transcriptional cascade of SlARF4-SlMYB99-GPP/GLDH/DHAR modulates AsA synthesis, while mitogen-activated protein kinase SlMAPK8 not only phosphorylates SlMYB99, but also activates its transcriptional activity. Both SlMYB99 and SlMYB11 proteins physically interact with each other, thereby synergistically regulating AsA biosynthesis by upregulating the expression of GPP, GLDH, and DHAR genes. Collectively, these results demonstrate that auxin and abscisic acid antagonistically regulate AsA biosynthesis during development and drought tolerance in tomato via the SlMAPK8-SlARF4-SlMYB99/11 module. These findings provide new insights into the mechanism underlying phytohormone regulation of AsA biosynthesis and provide a theoretical basis for the future development of high AsA plants via molecular breeding.
PMID: 37247338
New Phytol , IF:10.151 , 2023 May doi: 10.1111/nph.18947
Disruption of the amino acid transporter CsAAP2 inhibits auxin-mediated root development in cucumber.
Beijing Key Laboratory of Growth and Developmental Regulation for Protected Vegetable Crops, College of Horticulture, China Agricultural University, Beijing, 100193, China.
Amino acid transporters are the principal mediators of organic nitrogen distribution within plants and are essential for plant growth and development. Despite this importance, relatively few amino acid transporter genes have been explored and elucidated in cucumber (Cucumis sativus). Here, a total of 86 amino acid transporter genes were identified in the cucumber genome. We further identified Amino Acid Permease (AAP) subfamily members that exhibited distinct expression patterns in different tissues. We found that the CsAAP2 as a candidate gene encoding a functional amino acid transporter is highly expressed in cucumber root vascular cells. CsAAP2 knockout lines exhibited arrested development of root meristem, which then caused the delayed initiation of lateral root and the inhibition of root elongation. What is more, the shoot growth of aap2 mutants was strongly retarded due to defects in cucumber root development. Moreover, aap2 mutants exhibited higher concentrations of amino acids and lignin in roots. We found that the mutant roots had a stronger ability to acidize medium. Furthermore, in the aap2 mutants, polar auxin transport was disrupted in the root tip, leading to high auxin levels in roots. Interestingly, slightly alkaline media rescued their severely reduced root growth by stimulating auxin pathway.
PMID: 37129077
New Phytol , IF:10.151 , 2023 Jun , V238 (5) : P1813-1824 doi: 10.1111/nph.18898
Loss-of-function of gynoecium-expressed phospholipase pPLAIIgamma triggers maternal haploid induction in Arabidopsis.
Department of Applied Plant Science, College of Agriculture and Life Sciences, Chonnam National University, Gwangju, 61186, Korea.; Interdisciplinary Program in IT-Bio Convergence System, Chonnam National University, Gwangju, 61186, Korea.; Laboratoire Reproduction et Developpement des Plantes, Univ Lyon, ENS de Lyon, UCB Lyon 1, CNRS, INRAE, Lyon, F-69342, France.
Production of in planta haploid embryos that inherit chromosomes from only one parent can greatly increase breeding efficiency via quickly generating homozygous plants, called doubled haploid. One of the main players of in planta haploid induction is a pollen-specific phospholipase A, which is able, when mutated, to induce in vivo haploid induction in numerous monocots. However, no functional orthologous gene has been identified in dicots plants. Here, we show that loss-of-function of gynoecium-expressed phospholipase AII (pPLAIIgamma) triggers maternal haploid plants in Arabidopsis, at an average rate of 1.07%. Reciprocal crosses demonstrate that haploid plants are triggered from the female side and not from the pollen, and the haploid plants carry the maternal genome. Promoter activity of pPLAIIgamma shows enriched expression in the funiculus of flower development stages 13 and 18, and pPLAIIgamma fused to yellow fluorescent protein reveals a plasma-membrane localization Interestingly, the polar localized PIN1 at the basal plasma membrane of the funiculus was all internalized in pplaIIgamma mutants, suggesting that altered PIN1 localization in female organ could play a role in maternal haploid induction.
PMID: 36967578
New Phytol , IF:10.151 , 2023 Jun , V238 (5) : P1924-1941 doi: 10.1111/nph.18879
AZG1 is a cytokinin transporter that interacts with auxin transporter PIN1 and regulates the root stress response.
Instituto Multidisciplinario de Biologia Vegetal, Velez Sarsfield 249, 5000, Cordoba, Argentina.; Molecular Plant Physiology, Institute of Cellular and Molecular Botany, University of Bonn, Kirschallee 1, 53115, Bonn, Germany.; Institute of Biology II, University of Freiburg, Schanzlestrasse 1, 79104, Freiburg, Germany.; Conservation Ecology, Department Biology, Philipps-Universitat Marburg, Karl-von-Frisch-Strasse 8, 35032, Marburg, Germany.; Laboratory of Growth Regulators, Institute of Experimental Botany ASCR and Palacky, Slechtitelu 27, 783 71, Olomouc, Czech Republic.; Zentrum fur Molekularbiologie der Pflanzen, Universitat Tubingen, Auf der Morgenstelle 1, 72076, Tubingen, Germany.; Faculty of Medicine, Institute of Physiology II, University of Freiburg, Hermann-Herder-Strasse 7, 79104, Freiburg, Germany.; Labormedizinisches Zentrum Ostschweiz, Lagerstrasse 30, 9470, Buchs, SG, Switzerland.; Centre of Biological Systems Analysis, University of Freiburg, 79104, Freiburg, Germany.; BIOSS Centre for Biological Signalling Studies, University of Freiburg, 79104, Freiburg, Germany.
An environmentally responsive root system is crucial for plant growth and crop yield, especially in suboptimal soil conditions. This responsiveness enables the plant to exploit regions of high nutrient density while simultaneously minimizing abiotic stress. Despite the vital importance of root systems in regulating plant growth, significant gaps of knowledge exist in the mechanisms that regulate their architecture. Auxin defines both the frequency of lateral root (LR) initiation and the rate of LR outgrowth. Here, we describe a search for proteins that regulate root system architecture (RSA) by interacting directly with a key auxin transporter, PIN1. The native separation of Arabidopsis plasma membrane protein complexes identified several PIN1 co-purifying proteins. Among them, AZG1 was subsequently confirmed as a PIN1 interactor. Here, we show that, in Arabidopsis, AZG1 is a cytokinin (CK) import protein that co-localizes with and stabilizes PIN1, linking auxin and CK transport streams. AZG1 expression in LR primordia is sensitive to NaCl, and the frequency of LRs is AZG1-dependent under salt stress. This report therefore identifies a potential point for auxin:cytokinin crosstalk, which shapes RSA in response to NaCl.
PMID: 36918499
New Phytol , IF:10.151 , 2023 May , V238 (4) : P1379-1385 doi: 10.1111/nph.18864
Lateral root branching: evolutionary innovations and mechanistic divergence in land plants.
Department of Biosciences and Bioengineering, Indian Institute of Technology Roorkee, Roorkee, 247667, Uttarakhand, India.; Center for Organismal Studies, University of Heidelberg, Heidelberg, 69120, Germany.
The root system architecture in plants is a result of multiple evolutionary innovations over time in response to changing environmental cues. Dichotomy and endogenous lateral branching in the roots evolved in lycophytes lineage but extant seed plants use lateral branching instead. This has led to the development of complex and adaptive root systems, with lateral roots playing a key role in this process exhibiting conserved and divergent features in different plant species. The study of lateral root branching in diverse plant species can shed light on the orderly yet distinct nature of postembryonic organogenesis in plants. This insight provides an overview of the diversity in lateral root (LR) development in various plant species during the evolution of root system in plants.
PMID: 36882384
New Phytol , IF:10.151 , 2023 May , V238 (4) : P1498-1515 doi: 10.1111/nph.18854
PIN-FORMED is required for shoot phototropism/gravitropism and facilitates meristem formation in Marchantia polymorpha.
School of Biological Sciences, Monash University, Melbourne, Vic., 3800, Australia.; ARC Centre of Excellence for Plant Success in Nature and Agriculture, Monash University, Melbourne, Vic., 3800, Australia.
PIN-FORMED auxin efflux transporters, a subclass of which is plasma membrane-localised, mediate a variety of land-plant developmental processes via their polar localisation and subsequent directional auxin transport. We provide the first characterisation of PIN proteins in liverworts using Marchantia polymorpha as a model system. Marchantia polymorpha possesses a single PIN-FORMED gene, whose protein product is predicted to be plasma membrane-localised, MpPIN1. To characterise MpPIN1, we created loss-of-function alleles and produced complementation lines in both M. polymorpha and Arabidopsis. In M. polymorpha, gene expression and protein localisation were tracked using an MpPIN1 transgene encoding a translationally fused fluorescent protein. Overexpression of MpPIN1 can partially complement loss of an orthologous gene, PIN-FORMED1, in Arabidopsis. In M. polymorpha, MpPIN1 influences development in numerous ways throughout its life cycle. Most notably, MpPIN1 is required to establish gemmaling dorsiventral polarity and for orthotropic growth of gametangiophore stalks, where MpPIN1 is basally polarised. PIN activity is largely conserved within land plants, with PIN-mediated auxin flow providing a flexible mechanism to organise growth. Specifically, PIN is fundamentally linked to orthotropism and to the establishment of de novo meristems, the latter potentially involving the formation of both auxin biosynthesis maxima and auxin-signalling minima.
PMID: 36880411
New Phytol , IF:10.151 , 2023 May , V238 (3) : P1146-1162 doi: 10.1111/nph.18775
RRS1 shapes robust root system to enhance drought resistance in rice.
Beijing Key Laboratory of Crop Genetic Improvement, College of Agronomy and Biotechnology, China Agricultural University, Beijing, 100193, China.; Sanya Institute of China Agricultural University, Sanya, 572025, China.; Shandong Rice Research Institute, Shandong Academy of Agricultural Sciences, Jinan, 250100, Shandong, China.; Sanya Institute, Hainan Academy of Agricultural Sciences, Sanya, 572025, China.
A strong root system facilitates the absorption of water and nutrients from the soil, to improve the growth of crops. However, to date, there are still very few root development regulatory genes that can be used in crop breeding for agriculture. In this study, we cloned a negative regulator gene of root development, Robust Root System 1 (RRS1), which encodes an R2R3-type MYB family transcription factor. RRS1 knockout plants showed enhanced root growth, including longer root length, longer lateral root length, and larger lateral root density. RRS1 represses root development by directly activating the expression of OsIAA3 which is involved in the auxin signaling pathway. A natural variation in the coding region of RRS1 changes the transcriptional activity of its protein. RRS1(T) allele, originating from wild rice, possibly increases root length by means of weakening regulation of OsIAA3. Knockout of RRS1 enhances drought resistance by promoting water absorption and improving water use efficiency. This study provides a new gene resource for improving root systems and cultivating drought-resistant rice varieties with important values in agricultural applications.
PMID: 36862074
New Phytol , IF:10.151 , 2023 May , V238 (3) : P971-976 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 Apr , V238 (2) : P673-687 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 Apr , V238 (1) : P142-154 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 Apr , V238 (1) : P125-141 doi: 10.1111/nph.18625
Hormonal control of medial-lateral growth and vein formation in the maize leaf.
Division of Biological Sciences, Interdisciplinary Plant Group, and Missouri Maize Center, University of Missouri, Columbia, MO, 65211, USA.; Department of Biology, School of Science and Engineering, Ateneo de Manila University, Loyola Heights, Quezon City, Metro Manila, 1108, Philippines.
Parallel veins are characteristic of monocots, including grasses (Poaceae). Therefore, how parallel veins develop as the leaf grows in the medial-lateral (ML) dimension is a key question in grass leaf development. Using fluorescent protein reporters, we mapped auxin, cytokinin (CK), and gibberellic acid (GA) response patterns in maize (Zea mays) leaf primordia. We further defined the roles of these hormones in ML growth and vein formation through combinatorial genetic analyses and measurement of hormone concentrations. We discovered a novel pattern of auxin response in the adaxial protoderm that we hypothesize has important implications for the orderly formation of 3 degrees veins early in leaf development. In addition, we found an auxin transport and response pattern in the margins that correlate with the transition from ML to proximal-distal growth. We present evidence that auxin efflux precedes CK response in procambial strand development. We also determined that GA plays an early role in the shoot apical meristem as well as a later role in the primordium to restrict ML growth. We propose an integrative model whereby auxin regulates ML growth and vein formation in the maize leaf through control of GA and CK.
PMID: 36404129
Plant Biotechnol J , IF:9.803 , 2023 May doi: 10.1111/pbi.14054
A systematic dissection in oilseed rape provides insights into the genetic architecture and molecular mechanism of yield heterosis.
Oil Crops Research Institute of the Chinese Academy of Agricultural Sciences, Key Laboratory of Biology and Genetic Improvement of Oil Crops, Ministry of Agriculture and Rural Affairs, Wuhan, China.; National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan, China.; State Key Laboratory of Biocatalysis and Enzyme Engineering, College of Life Sciences, Hubei University, Wuhan, China.; Zhengzhou Fruit Research Institute of the Chinese Academy of Agricultural Sciences, The Laboratory of Melon Crops, Zhengzhou, China.; Key Laboratory for Molecular Genetic Mechanisms and Intervention Research on High Altitude Disease of Tibet Autonomous Region, School of Medicine, Xizang Minzu University, Xianyang, China.; Hubei Hongshan Laboratory (HHL), Wuhan, China.; State Agricultural Biotechnology Centre, Centre for Crop and Food Innovation, Food Futures Institute, Murdoch University, Murdoch, WA, Australia.
Heterosis refers to the better performance of cross progeny compared with inbred parents, and its utilization contributes greatly to agricultural production. Several hypotheses have been proposed to explain heterosis mainly including dominance, over-dominance (or pseudo-overdominance) and epistasis. However, systematic dissection and verification of these hypotheses are rarely documented. Here, comparison of heterosis level across different traits showed that the strong heterosis of composite traits (such as yield) could be attributed to the multiplicative effects of moderate heterosis of component traits, whether at the genome or locus level. Yield heterosis was regulated by a complex trait-QTL network that was characterized by obvious centre-periphery structure, hub QTL, complex up/downstream and positive/negative feedback relationships. More importantly, we showed that better-parent heterosis on yield could be produced in a cross of two near-isogenic lines by the pyramiding and complementation of two major heterotic QTL showing partial-dominance on yield components. The causal gene (BnaA9.CYP78A9) of QC14 was identified, and its heterotic effect results from the heterozygous status of a CACTA-like transposable element in its upstream regulatory region, which led to partial dominance at expression and auxin levels, thus resulting in non-additive expression of downstream responsive genes involved in cell cycle and proliferation, eventually leading to the heterosis of cell number. Taken together, the results at the phenotypic, genetic and molecular levels were highly consistent, which demonstrated that the pyramiding effect of heterotic QTL and the multiplicative effect of individual component traits could well explain substantial parts of yield heterosis in oilseed rape. These results provide in-depth insights into the genetic architecture and molecular mechanism of yield heterosis.
PMID: 37170717
Plant Biotechnol J , IF:9.803 , 2023 Apr doi: 10.1111/pbi.14046
Auxin inhibits lignin and cellulose biosynthesis in stone cells of pear fruit via the PbrARF13-PbrNSC-PbrMYB132 transcriptional regulatory cascade.
College of Horticulture, State Key Laboratory of Crop Genetics & Germplasm Enhancement and Utilization, Nanjing Agricultural University, Nanjing, Jiangsu, China.; The New Zealand Institute for Plant and Food Research Ltd, Mt Albert Research Centre, Auckland, New Zealand.; College of Horticultural Science and Engineering, Shandong Agricultural University, Taian, Shandong, China.
Stone cells are often present in pear fruit, and they can seriously affect the fruit quality when present in large numbers. The plant growth regulator NAA, a synthetic auxin, is known to play an active role in fruit development regulation. However, the genetic mechanisms of NAA regulation of stone cell formation are still unclear. Here, we demonstrated that exogenous application of 200 muM NAA reduced stone cell content and also significantly decreased the expression level of PbrNSC encoding a transcriptional regulator. PbrNSC was shown to bind to an auxin response factor, PbrARF13. Overexpression of PbrARF13 decreased stone cell content in pear fruit and secondary cell wall (SCW) thickness in transgenic Arabidopsis plants. In contrast, knocking down PbrARF13 expression using virus-induced gene silencing had the opposite effect. PbrARF13 was subsequently shown to inhibit PbrNSC expression by directly binding to its promoter, and further to reduce stone cell content. Furthermore, PbrNSC was identified as a positive regulator of PbrMYB132 through analyses of co-expression network of stone cell formation-related genes. PbrMYB132 activated the expression of gene encoding cellulose synthase (PbrCESA4b/7a/8a) and lignin laccase (PbrLAC5) binding to their promotors. As expected, overexpression or knockdown of PbrMYB132 increased or decreased stone cell content in pear fruit and SCW thickness in Arabidopsis transgenic plants. In conclusion, our study shows that the 'PbrARF13-PbrNSC-PbrMYB132' regulatory cascade mediates the biosynthesis of lignin and cellulose in stone cells of pear fruit in response to auxin signals and also provides new insights into plant SCW formation.
PMID: 37031416
Plant Biotechnol J , IF:9.803 , 2023 Jun , V21 (6) : P1217-1228 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
Cell Rep , IF:9.423 , 2023 May , V42 (6) : P112565 doi: 10.1016/j.celrep.2023.112565
ERF1 inhibits lateral root emergence by promoting local auxin accumulation and repressing ARF7 expression.
Division of Life Sciences and Medicine, Division of Molecular & Cell Biophysics, Hefei National Science Center for Interdisciplinary Sciences at the Microscale, MOE Key Laboratory for Membraneless Organelles and Cellular Dynamics, University of Science and Technology of China, The Innovation Academy of Seed Design, Chinese Academy of Sciences, Hefei, Anhui Province 230027, China. Electronic address: zhaopingxia2008@163.com.; Division of Life Sciences and Medicine, Division of Molecular & Cell Biophysics, Hefei National Science Center for Interdisciplinary Sciences at the Microscale, MOE Key Laboratory for Membraneless Organelles and Cellular Dynamics, University of Science and Technology of China, The Innovation Academy of Seed Design, Chinese Academy of Sciences, Hefei, Anhui Province 230027, China.; College of Life Sciences, Anhui Agricultural University, Hefei, Anhui Province 230036, China.; Division of Life Sciences and Medicine, Division of Molecular & Cell Biophysics, Hefei National Science Center for Interdisciplinary Sciences at the Microscale, MOE Key Laboratory for Membraneless Organelles and Cellular Dynamics, University of Science and Technology of China, The Innovation Academy of Seed Design, Chinese Academy of Sciences, Hefei, Anhui Province 230027, China. Electronic address: xiangcb@ustc.edu.cn.
Lateral roots (LRs) are crucial for plants to sense environmental signals in addition to water and nutrient absorption. Auxin is key for LR formation, but the underlying mechanisms are not fully understood. Here, we report that Arabidopsis ERF1 inhibits LR emergence by promoting local auxin accumulation with altered distribution and regulating auxin signaling. Loss of ERF1 increases LR density compared with the wild type, whereas ERF1 overexpression causes the opposite phenotype. ERF1 enhances auxin transport by upregulating PIN1 and AUX1, resulting in excessive auxin accumulation in the endodermal, cortical, and epidermal cells surrounding LR primordia. Furthermore, ERF1 represses ARF7 transcription, thereby downregulating the expression of cell-wall remodeling genes that facilitate LR emergence. Together, our study reveals that ERF1 integrates environmental signals to promote local auxin accumulation with altered distribution and repress ARF7, consequently inhibiting LR emergence in adaptation to fluctuating environments.
PMID: 37224012
EMBO Rep , IF:8.807 , 2023 Apr , V24 (4) : 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 May doi: 10.1093/plphys/kiad309
Cell Signaling in the Shoot Apical Meristem.
College of Life Sciences, University of Chinese Academy of Sciences, Beijing, 100049, China.; State Key Laboratory of Protein and Plant Gene Research, School of Life Sciences, Peking University, Beijing 100871, China.; Peking-Tsinghua Center for Life Sciences, Center for Quantitative Biology, Academy for Advanced Interdisciplinary Studies, Peking University, Beijing 100871, China.; Peking University Institute of Advanced Agricultural Sciences, Shandong Laboratory of Advanced Agricultural Sciences in Weifang, Weifang, Shandong 261325, China.
Distinct from animals, plants maintain organogenesis from specialized tissues termed meristems throughout life. In the shoot apex, the shoot apical meristem (SAM) produces all aerial organs, such as leaves, from its periphery. For this, the SAM needs to precisely balance stem cell renewal and differentiation, which is achieved through dynamic zonation of the SAM, and cell signaling within functional domains is key for SAM functions. The WUSCHEL-CLAVATA feedback loop plays a key role in SAM homeostasis, and recent studies have uncovered new components, expanding our understanding of the spatial expression and signaling mechanism. Advances in polar auxin transport and signaling have contributed to knowledge of the multifaceted roles of auxin in the SAM and organogenesis. Finally, single-cell techniques have expanded our understanding of the cellular functions within the shoot apex at single-cell resolution. In this review, we summarize the most up-to-date understanding of cell signaling in the SAM and focus on the multiple levels of regulation of SAM formation and maintenance.
PMID: 37224874
Plant Physiol , IF:8.34 , 2023 May doi: 10.1093/plphys/kiad293
GmGAMYB-BINDING PROTEIN 1 promotes Small Auxin-Up RNA gene transcription to modulate soybean maturity and height.
Key Laboratory of Soybean Biology of Ministry of Education China, Northeast Agricultural University, Harbin 150030, China.
Flowering time, maturity, and plant height are crucial agronomic traits controlled by photoperiod that affect soybean (Glycine max [L.] Merr.) yield and regional adaptability. It is important to cultivate soybean cultivars of earlier maturity that adapt to high latitudes. GAMYB binding protein 1 (GmGBP1), a member of the SNW/SKIP family of transcriptional co-regulators in soybean, is induced by short days and interacts with transcription factor GAMYB (GmGAMYB) during photoperiod control of flowering time and maturity. In the present study, GmGBP1:GmGBP1 soybean showed the phenotypes of earlier maturity and higher plant height. Chromatin immunoprecipitation sequencing assays (ChIP-seq) of GmGBP1-binding sites and RNA sequencing (RNA-seq) of differentially expressed transcripts in GmGBP1:GmGBP1 further identified potential targets of GmGBP1, including small auxin-up RNA (GmSAUR). GmSAUR:GmSAUR soybean also showed earlier maturity and higher plant height. GmGBP1 interacted with GmGAMYB, bound to the promoter of GmSAUR, and promoted the expression of FLOWER LOCUS T homologs 2a (GmFT2a) and FLOWERING LOCUS D LIKE 19 (GmFDL19). Flowering repressors such as GmFT4 were negatively regulated, resulting in earlier flowering and maturity. Furthermore, the interaction of GmGBP1 with GmGAMYB increased the gibberellin (GA) signal to promote height and hypocotyl elongation by activating GmSAUR; GmSAUR bound to the promoter of the GA-positive activating regulator gibberellic acid-stimulated Arabidopsis 32 (GmGASA32). These results suggested a photoperiod regulatory pathway in which the interaction of GmGBP1 with GmGAMYB directly activated GmSAUR to promote earlier maturity and plant height in soybean.
PMID: 37204820
Plant Physiol , IF:8.34 , 2023 May doi: 10.1093/plphys/kiad289
miR171-targeted SCARECROW-LIKE genes CsSCL2 and CsSCL3 regulate somatic embryogenesis in citrus.
National Key Laboratory for Germplasm Innovation & Utilization of Horticultural Crops, College of Horticulture and Forestry Sciences, Huazhong Agricultural University, Wuhan 430070, China.; Hubei Hongshan Laboratory, Wuhan 430070, China.
Somatic embryogenesis (SE) is a key regeneration pathway in various biotechnology approaches to crop improvement, especially for economically important perennial woody crops like citrus. However, maintenance of SE capability has long been a challenge and becomes a bottleneck in biotechnology-facilitated plant improvement. In the embryogenic callus (EC) of citrus, we identified two csi-miR171c targeted SCARECROW-LIKE genes CsSCL2 and CsSCL3 (CsSCL2/3), which exert positive feedback regulation on csi-miR171c expression. Suppression of CsSCL2 expression by RNA interference (RNAi) enhanced SE in citrus callus. A thioredoxin superfamily protein CsClot was identified as an interactive protein of CsSCL2/3. Overexpression of CsClot disturbed reactive oxygen species (ROS) homeostasis in EC and enhanced SE. ChIP-Seq and RNA-Seq identified 660 genes directly suppressed by CsSCL2 that were enriched in biological processes including development related processes, auxin signaling pathway and cell wall organization. CsSCL2/3 bound to the promoters of regeneration-related genes, such as WUSCHEL-RELATED HOMEOBOX 2 (CsWOX2), CsWOX13 and Lateral Organ Boundaries Domain 40 (LBD40), and repressed their expression. Overall, CsSCL2/3 modulate ROS homeostasis through the interactive protein CsClot and directly suppress the expression of regeneration-related genes, thus regulating SE in citrus. We uncovered a regulatory pathway of miR171c-targeted CsSCL2/3 in SE, which shed light on the mechanism of SE and regeneration capability maintenance in citrus.
PMID: 37204807
Plant Physiol , IF:8.34 , 2023 May doi: 10.1093/plphys/kiad264
Computer models of cell polarity establishment in plants.
Centro de Biotecnologia y Genomica de Plantas, Universidad Politecnica de Madrid (UPM) - Instituto Nacional de Investigacion y Tecnologia Agraria y Alimentaria (INIA), Pozuelo de Alarcon (Madrid), Spain.
Plant development is a complex task and many processes involve changes in the asymmetric subcellular distribution of cell components that strongly depend on cell polarity. Cell polarity regulates anisotropic growth, and polar localization of membrane proteins, and helps to identify the cell's position relative to its neighbors within an organ. Cell polarity is critical in a variety of plant developmental processes including embryogenesis, cell division, and response to external stimuli. The most conspicuous downstream effect of cell polarity is the polar transport of the phytohormone auxin, which is the only known hormone transported in a polar fashion in and out of cells by specialized exporters and importers. The biological processes behind the establishment of cell polarity are still unknown and researchers have proposed several models which have been tested using computer simulations. The evolution of computer models has progressed in tandem with scientific discoveries, which have highlighted the importance of genetic, chemical, and mechanical input in determining cell polarity and regulating polarity-dependent processes like anisotropic growth, protein subcellular localization, and the development of organ shapes. The purpose of this review is to provide a comprehensive overview of the current understanding of computer models of cell polarity establishment in plants, focusing on the molecular and cellular mechanisms, the proteins involved, and the current state of the field.
PMID: 37144853
Plant Physiol , IF:8.34 , 2023 Apr doi: 10.1093/plphys/kiad254
Integration of multiple stress signals in plants using synthetic Boolean logic gates.
Department of Biological Sciences, University of North Texas, Denton, TX, USA.; BioDiscovery Institute, University of North Texas, Denton, TX, USA.
As photosynthetic organisms, plants have a potential role in the sustainable production of high-value products such as medicines, biofuels, and chemical feedstocks. With effective engineering using synthetic biology approaches, plant-based platforms could conceivably be designed to minimize the costs and waste of production for materials that would otherwise be uneconomical. Additionally, modern agricultural crops could be engineered to be more productive, resilient, or restorative in different or rapidly changing environments and climates. Information-processing genetic devices and circuits containing multiple interacting parts that behave predictably must be developed to achieve these complex goals. A genetic Boolean AND logic gate is a device that computes the presence or absence of two inputs (signals, stimuli) and produces an output (response) only when both inputs are present. We optimized individual genetic components and used synthetic protein heterodimerizing domains to rationally assemble genetic AND logic gates that integrate two hormonal inputs in transgenic Arabidopsis thaliana plants. These AND gates produce an output only in the presence of both abscisic acid and auxin but not when either or neither hormone is present. The AND logic gate can also integrate signals resulting from two plant stresses, cold temperature and bacterial infection, to produce a response. The design principles used here are generalizable, and, therefore, multiple orthogonal AND gates could be assembled and rationally layered to process complex genetic information in plants. These layered logic gates may be used in genetic circuits to probe fundamental questions in plant biology, such as hormonal crosstalk, in addition to plant engineering for bioproduction.
PMID: 37119276
Plant Physiol , IF:8.34 , 2023 Apr doi: 10.1093/plphys/kiad248
WAVE-DAMPENED2-LIKE4 modulates the hyper-elongation of light-grown hypocotyl cells.
Department of Biology, Indiana University, Bloomington, Indiana, 47405.
Light, temperature, water, and nutrient availability influence how plants grow to maximize access to resources. Axial growth, the linear extension of tissues by coordinated axial cell expansion, plays a central role in these adaptive morphological responses. Using Arabidopsis (Arabidopsis thaliana) hypocotyl cells to explore axial growth control mechanisms, we investigated WAVE-DAMPENED2-LIKE4 (WDL4), an auxin-induced, microtubule-associated protein and member of the larger WDL gene family shown to modulate hypocotyl growth under changing environmental conditions. Loss-of-function wdl4 seedlings exhibited a hyper-elongation phenotype under light conditions, continuing to elongate when wild type Col-0 hypocotyls arrested and reaching 150-200% of wild type length before shoot emergence. wdl4 seedling hypocotyls showed dramatic hyper-elongation (500%) in response to temperature elevation, indicating an important role in morphological adaptation to environmental cues. WDL4 associated with microtubules under both light and dark growth conditions, and no evidence was found for altered microtubule array patterning in loss-of-function wdl4 mutants under various conditions. Examination of hormone responses showed altered sensitivity to ethylene and evidence for changes in the spatial distribution of the auxin-dependent DR5:GFP reporter. Our data provide evidence that WDL4 regulates hypocotyl cell elongation without substantial changes to microtubule array patterning, suggesting an unconventional role in axial growth control.
PMID: 37096683
Plant Physiol , IF:8.34 , 2023 Apr doi: 10.1093/plphys/kiad205
Modulating auxin response stabilizes tomato fruit set.
The Robert H. Smith Institute of Plant Sciences and Genetics in Agriculture, Hebrew University, PO Box 12, Rehovot 76100, Israel.; Department of Cell and Metabolic Biology, Leibniz Institute of Plant Biochemistry, 06120 Halle, Germany.; Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599-3280.; Umea Plant Science Centre, Department of Forest Genetics and Plant Physiology, Swedish University of Agricultural Sciences, 901 83 Umea, Sweden.
Fruit formation depends on successful fertilization and is highly sensitive to weather fluctuations that affect pollination. Auxin promotes fruit initiation and growth following fertilization. Class A auxin response factors (Class A ARFs) repress transcription in the absence of auxin and activate transcription in its presence. Here we explore how multiple members of the ARF family regulate fruit set and fruit growth in tomato (Solanum lycopersicum) and Arabidopsis thaliana, and test whether reduction of SlARF activity improves yield stability in fluctuating temperatures. We found that several tomato Slarf mutant combinations produced seedless parthenocarpic fruits, most notably mutants deficient in SlARF8A and SlARF8B genes. Arabidopsis Atarf8 mutants deficient in the orthologous gene had less complete parthenocarpy than did tomato Slarf8a Slarf8b mutants. Conversely, Atarf6 Atarf8 double mutants had reduced fruit growth after fertilization. AtARF6 and AtARF8 likely switch from repression to activation of fruit growth in response to a fertilization-induced auxin increase in gynoecia. Tomato plants with reduced SlARF8A and SlARF8B gene dosage had substantially higher yield than the wild type under controlled or ambient hot and cold growth conditions. In field trials, partial reduction in the SlARF8 dose increased yield under extreme temperature with minimal pleiotropic effects. The stable yield of the mutant plants resulted from a combination of early onset of fruit set, more fruit-bearing branches and more flowers setting fruits. Thus, ARF8 proteins mediate the control of fruit set, and relieving this control with Slarf8 mutations may be utilized in breeding to increase yield stability in tomato and other crops.
PMID: 37032117
Plant Physiol , IF:8.34 , 2023 May , V192 (1) : P28-30 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, 999077 Hong Kong, China.; State Key Laboratory of Agrobiotechnology, The Chinese University of Hong Kong, 999077 Hong Kong, China.
PMID: 36797804
Plant Physiol , IF:8.34 , 2023 May , V192 (1) : P25-27 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, Davis, CA 95616, USA.
PMID: 36788762
Plant Physiol , IF:8.34 , 2023 May , V192 (1) : P256-273 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 the 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 2 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 (PM). 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 PM 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 Apr , V191 (4) : P2447-2460 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 (cre1) mutant. 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 the 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 that 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 that IAR33 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, which normally 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 May , V192 (1) : P582-600 doi: 10.1093/plphys/kiac581
The Mediator complex subunit MED25 interacts with HDA9 and PIF4 to regulate thermomorphogenesis.
Laboratory of Plant Physiology, Wageningen University & Research, Droevendaalsesteeg 1, 6708 PB Wageningen, The Netherlands.; Temasek Life Science Laboratory, 1 Research Link, National University of Singapore, Singapore 117604, Singapore.; Plant Stress Resilience, Institute of Environmental Biology, Utrecht University, Padualaan 8, 3584 CH Utrecht, the Netherlands.; Italian National Agency for New Technologies, Energy and Sustainable Economic Development (ENEA), Trisaia Research Centre, S.S. Ionica, km 419.5, 75026 Rotondella (Matera), Italy.
Thermomorphogenesis is, among other traits, characterized by enhanced hypocotyl elongation due to the induction of auxin biosynthesis genes like YUCCA8 by transcription factors, most notably PHYTOCHROME INTERACTING FACTOR 4 (PIF4). Efficient binding of PIF4 to the YUCCA8 locus under warmth depends on HISTONE DEACETYLASE 9 (HDA9) activity, which mediates histone H2A.Z depletion at the YUCCA8 locus. However, HDA9 lacks intrinsic DNA-binding capacity, and how HDA9 is recruited to YUCCA8, and possibly other PIF4-target sites, is currently not well understood. The Mediator complex functions as a bridge between transcription factors bound to specific promoter sequences and the basal transcription machinery containing RNA polymerase II. Mutants of Mediator component Mediator25 (MED25) exhibit reduced hypocotyl elongation and reduced expression of YUCCA8 at 27 degrees C. In line with a proposed role for MED25 in thermomorphogenesis in Arabidopsis (Arabidopsis thaliana), we demonstrated an enhanced association of MED25 to the YUCCA8 locus under warmth and interaction of MED25 with both PIF4 and HDA9. Genetic analysis confirmed that MED25 and HDA9 operate in the same pathway. Intriguingly, we also showed that MED25 destabilizes HDA9 protein. Based on our findings, we propose that MED25 recruits HDA9 to the YUCCA8 locus by binding to both PIF4 and HDA9.
PMID: 36537119
Environ Pollut , IF:8.071 , 2023 Apr , 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
Curr Opin Plant Biol , IF:7.834 , 2023 May , V74 : P102377 doi: 10.1016/j.pbi.2023.102377
How do plants reprogramme the fate of differentiated cells?
RIKEN Center for Sustainable Resource Science, 1-7-22 Suehirocho, Tsurumi, Yokohama, Kanagawa, 230-0045, Japan. Electronic address: hatsune.morinaka@riken.jp.; RIKEN Center for Sustainable Resource Science, 1-7-22 Suehirocho, Tsurumi, Yokohama, Kanagawa, 230-0045, Japan; Department of Biological Sciences, Graduate School of Science, The University of Tokyo, Hongo 7-3-1, Bunkyo-ku, Tokyo, 113-0033, Japan.; RIKEN Center for Sustainable Resource Science, 1-7-22 Suehirocho, Tsurumi, Yokohama, Kanagawa, 230-0045, Japan; Japan Science and Technology Agency, Precursory Research for Embryonic Science and Technology (PRESTO), 7, Gobancho, Chiyoda-ku, Tokyo, 102-0076, Japan.; RIKEN Center for Sustainable Resource Science, 1-7-22 Suehirocho, Tsurumi, Yokohama, Kanagawa, 230-0045, Japan; Department of Biological Sciences, Graduate School of Science, The University of Tokyo, Hongo 7-3-1, Bunkyo-ku, Tokyo, 113-0033, Japan. Electronic address: keiko.sugimoto@riken.jp.
Being able to change cell fate after differentiation highlights the remarkable developmental plasticity of plant cells. Recent studies show that phytohormones, such as auxin and cytokinin, promote cell cycle reactivation, a critical first step to reprogramme mitotically inactive, differentiated cells into organogenic stem cells. Accumulating evidence suggests that wounding provides an additional cue to convert the identity of differentiated cells by promoting the loss of existing cell fate and/or acquisition of new cell fate. Differentiated cells can also alter cell fate without undergoing cell division and in this case, wounding and phytohormones induce master regulators that can directly assign new cell fate.
PMID: 37167921
Curr Opin Plant Biol , IF:7.834 , 2023 Apr , V72 : P102350 doi: 10.1016/j.pbi.2023.102350
Flavonols modulate plant development, signaling, and stress responses.
Climate Resilient Crop Production Laboratory, Division of Crop Biotechnics, Department of Biosystems, Katholieke Universiteit (KU) Leuven, Leuven, Belgium.; Department of Biology, Center for Molecular Signaling, Wake Forest University, Winston-Salem, NC, USA.; Climate Resilient Crop Production Laboratory, Division of Crop Biotechnics, Department of Biosystems, Katholieke Universiteit (KU) Leuven, Leuven, Belgium; Leuven Plant Institute, KU Leuven, Leuven, Belgium.; Department of Biology, Center for Molecular Signaling, Wake Forest University, Winston-Salem, NC, USA. Electronic address: muday@wfu.edu.
Flavonols are plant-specialized metabolites with important functions in plant growth and development. Isolation and characterization of mutants with reduced flavonol levels, especially the transparent testa mutants in Arabidopsis thaliana, have contributed to our understanding of the flavonol biosynthetic pathway. These mutants have also uncovered the roles of flavonols in controlling development in above- and below-ground tissues, notably in the regulation of root architecture, guard cell signaling, and pollen development. In this review, we present recent progress made towards a mechanistic understanding of flavonol function in plant growth and development. Specifically, we highlight findings that flavonols act as reactive oxygen species (ROS) scavengers and inhibitors of auxin transport in diverse tissues and cell types to modulate plant growth and development and responses to abiotic stresses.
PMID: 36870100
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
Plant Cell Environ , IF:7.228 , 2023 Jun , V46 (6) : P1921-1934 doi: 10.1111/pce.14580
SlIAA23-SlARF6 module controls arbuscular mycorrhizal symbiosis by regulating strigolactone biosynthesis in tomato.
Department of Horticulture, Zijingang Campus, Zhejiang University, Hangzhou, China.; Hainan Institute, Zhejiang University, Sanya, China.; Key Laboratory of Horticultural Plants Growth and Development, Agricultural Ministry of China, Hangzhou, China.
Auxins are a class of phytohormones with roles involved in the establishment and maintenance of the arbuscular mycorrhizal symbiosis (AMS). Auxin response factors (ARFs) and Auxin/Indole-acetic acids (AUX/IAAs), as two transcription factors of the auxin signaling pathway, coregulate the transcription of auxin response genes. However, the interrelation and regulatory mechanism of ARFs and AUX/IAAs in regulating AMS are still unclear. In this study, we found that the content of auxin in tomato roots increased sharply and revealed the importance of the auxin signaling pathway in the early stage of AMS. Notably, SlARF6 was found to play a negative role in AMF colonization. Silencing SlARF6 significantly increased the expression of AM-marker genes, as well as AMF-induced phosphorus uptake. SlIAA23 could interact with SlARF6 in vivo and in vitro, and promoted the AMS and phosphorus uptake. Interestingly, SlARF6 and SlIAA23 played a contrary role in strigolactone (SL) synthesis and accumulation in AMF-colonized roots of tomato plants. SlARF6 could directly bind to the AuxRE motif of the SlCCD8 promoter and inhibited its transcription, however, this effect was attenuated by SlIAA23 through interaction with SlARF6. Our results suggest that SlIAA23-SlARF6 coregulated tomato-AMS via an SL-dependent pathway, thus affecting phosphorus uptake in tomato plants.
PMID: 36891914
Plant Cell Environ , IF:7.228 , 2023 May , V46 (5) : P1562-1581 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 Apr , V46 (4) : P1075-1086 doi: 10.1111/pce.14494
Roles of auxin response factors in rice development and stress responses.
Joint International Research Laboratory of Metabolic & Developmental Sciences, SJTU-University of Adelaide Joint Centre for Agriculture and Health, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, China.
Auxin signalling plays a key role in various developmental processes ranging from embryogenesis to senescence in plants. Auxin response factor (ARF), a key component of auxin signalling, functions by binding to auxin response element within promoter of auxin response genes, activating or repressing the target genes. Increasing evidences show that ARFs are crucial for plant response to stresses. This review summarises the recent advance on the functions and their regulatory pathways of rice ARFs in development and responding to stresses. The importance of OsARFs is demonstrated by their roles in triggering various physiological, biochemical and molecular reactions to resist adverse environmental conditions. We also describe the transcriptional and post-transcriptional regulation of OsARFs, and discuss the major challenges in this area.
PMID: 36397176
Plant Cell Environ , IF:7.228 , 2023 Apr , V46 (4) : P1327-1339 doi: 10.1111/pce.14438
Homeobox transcription factors OsZHD1 and OsZHD2 induce inflorescence meristem activity at floral transition in rice.
Department of Plant Bioscience, College of Natural Resources and Life Science, Pusan National University, Miryang, Republic of Korea.; Life and Industry Convergence Research Institute, Pusan National University, Miryang, Republic of Korea.; Graduate School of Biotechnology and Crop Biotech Institute, Kyung Hee University, Yongin, Republic of Korea.
Floral transition starts in the leaves when florigens respond to various environmental and developmental factors. Among several regulatory genes that are preferentially expressed in the inflorescence meristem during the floral transition, this study examines the homeobox genes OsZHD1 and OsZHD2 for their roles in regulating this transition. Although single mutations in these genes did not result in visible phenotype changes, double mutations in these genes delayed flowering. Florigen expression was not altered in the double mutants, indicating that the delay was due to a defect in florigen signaling. Morphological analysis of shoot apical meristem at the early developmental stage indicated that inflorescence meristem development was significantly delayed in the double mutants. Overexpression of ZHD2 causes early flowering because of downstream signals after the generation of florigens. Expression levels of the auxin biosynthesis genes were reduced in the mutants and the addition of indole-3-acetic acid recovered the defect in the mutants, suggesting that these homeobox genes play a role in auxin biosynthesis. A rice florigen, RICE FLOWERING LOCUS T 1, binds to the promoter regions of homeobox genes. These results indicate that florigens stimulate the expression of homeobox genes, enhancing inflorescence development in the shoot apex.
PMID: 36120845
Plant Cell Environ , IF:7.228 , 2023 Apr , V46 (4) : P1157-1175 doi: 10.1111/pce.14434
Auxin plays a role in the adaptation of rice to anaerobic germination and seedling establishment.
Department of Bioagricultural Sciences, National Chiayi University, Chiayi, Taiwan.; Institute of Biomedical Sciences, National Chung Hsing University, Taichung, Taiwan.
Auxin is well known to stimulate coleoptile elongation and rapid seedling growth in the air. However, its role in regulating rice germination and seedling establishment under submergence is largely unknown. Previous studies revealed that excessive levels of indole-3-acetic acid(IAA) frequently cause the inhibition of plant growth and development. In this study, the high-level accumulation of endogenous IAA is observed under dark submergence, stimulating rice coleoptile elongation but limiting the root and primary leaf growth during anaerobic germination (AG). We found that oxygen and light can reduce IAA levels, promote the seedling establishment and enhance rice AG tolerance. miRNA microarray profiling and RNA gel blot analysis results show that the expression of miR167 is negatively regulated by submergence; it subsequently modulates the accumulation of free IAA through the miR167-ARF-GH3 pathway. The OsGH3-8 encodes an IAA-amido synthetase that functions to prevent free IAA accumulation. Reduced miR167 levels or overexpressing OsGH3-8 increase auxin metabolism, reduce endogenous levels of free IAA and enhance rice AG tolerance. Our studies reveal that poor seed germination and seedling growth inhibition resulting from excessive IAA accumulation would cause intolerance to submergence in rice, suggesting that a certain threshold level of auxin is essential for rice AG tolerance.
PMID: 36071575
Chemosphere , IF:7.086 , 2023 Jun , V326 : P138394 doi: 10.1016/j.chemosphere.2023.138394
Waste valorization as low-cost media engineering for auxin production from the newly isolated Streptomyces rubrogriseus AW22: Model development.
Laboratory of Mycology, Biotechnology and Microbial Activity (LaMyBAM), Department of Applied Biology, Constantine 1 University, BP, 325, Ain El Bey, Constantine, 25017, Algeria. Electronic address: wiemalloun@gmail.com.; Biotechnology Laboratory, National Higher School of Biotechnology, Ali Mendjeli University City, BP E66, 25100, Constantine, Algeria. Electronic address: m.berkani@ensbiotech.edu.dz.; Pharmaceutical Research and Sustainable Development Laboratory (ReMeDD), Department of Pharmaceutical Engineering, Faculty of Process Engineering, Constantine 3 University, Constantine, 25000, Algeria.; 3BIO-BioMatter Unit, Ecole Polytechnique de Bruxelles, Universite Libre de Bruxelles (ULB), Avenue F.D. Roosevelt, 50-CP 165/61, 1050, Brussels, Belgium.; Laboratory of Mycology, Biotechnology and Microbial Activity (LaMyBAM), Department of Applied Biology, Constantine 1 University, BP, 325, Ain El Bey, Constantine, 25017, Algeria.; The University of Johannesburg, Department of Chemical Engineering, P.O. Box 17011, Doornfontein, 2088, South Africa. Electronic address: cmdanesh@gmail.com.; Biotechnology Laboratory, National Higher School of Biotechnology, Ali Mendjeli University City, BP E66, 25100, Constantine, Algeria; Research Center in Industrial Technologies CRTI, P.O. Box 64, Cheraga 16014, Algiers, Algeria.; Department of Chemistry, College of Science, King Saud University, P.O. Box 2455, Riyadh, 11451, Saudi Arabia.
Indole-3-acetic acid (IAA) represents a crucial phytohormone regulating specific tropic responses in plants and functions as a chemical signal between plant hosts and their symbionts. The Actinobacteria strain of AW22 with high IAA production ability was isolated in Algeria for the first time and was characterized as Streptomyces rubrogriseus through chemotaxonomic analysis and 16 S rDNA sequence alignment. The suitable medium for a maximum IAA yield was engineered in vitro and in silico using machine learning-assisted modeling. The primary low-cost feedstocks comprised various concentrations of spent coffee grounds (SCGs) and carob bean grounds (CBGs) extracts. Further, we combined the Box-Behnken design from response surface methodology (BBD-RSM) with artificial neural networks (ANNs) coupled with the genetic algorithm (GA). The critical process parameters screened via Plackett-Burman design (PBD) served as BBD and ANN-GA inputs, with IAA yield as the output variable. Analysis of the putative IAA using thin-layer chromatography (TLC) and (HPLC) revealed Rf values equal to 0.69 and a retention time of 3.711 min, equivalent to the authentic IAA. AW 22 achieved a maximum IAA yield of 188.290 +/- 0.38 mug/mL using the process parameters generated by the ANN-GA model, consisting of L-Trp, 0.6%; SCG, 30%; T degrees , 25.8 degrees C; and pH 9, after eight days of incubation. An R(2) of 99.98%, adding to an MSE of 1.86 x 10(-5) at 129 epochs, postulated higher reliability of ANN-GA-approach in predicting responses, compared with BBD-RSM modeling exhibiting an R(2) of 76.28%. The validation experiments resulted in a 4.55-fold and 4.46-fold increase in IAA secretion, corresponding to ANN-GA and BBD-RSM models, respectively, confirming the validity of both models.
PMID: 36925000
J Exp Bot , IF:6.992 , 2023 May doi: 10.1093/jxb/erad185
PIN structures shed light on their mechanism of auxin efflux.
School of Life Sciences, University of Warwick, Coventry, CV4 7AL, UK.; Department of Biochemistry, University of Oxford, Oxford, OX1 3QU, UK.
Polar auxin transport is a quintessential feature of higher plant physiology and it has been known for many years that some of the primary drivers of polar auxin transport are the PIN-formed (PIN) auxin efflux proteins. Formative research established many key biochemical features of the transport system and discovered inhibitors such as 1-naphtylphthalamic acid (NPA), but the mechanism of action of PINs has remained elusive. This changed in 2022 with the publication of high-resolution structures of the membrane-spanning domains of three PIN proteins. The atomic structures and associated activity assays reveal that PINs use an elevator mechanism to transport auxin anions out of the cell. NPA was shown to be a competitive inhibitor that traps PINs in their inward-open conformation. The secrets of the hydrophilic cytoplasmic loop of PIN proteins remain to be discovered.
PMID: 37195878
J Exp Bot , IF:6.992 , 2023 May doi: 10.1093/jxb/erad178
Deciphering transcriptional mechanisms of maize internodal elongation by regulatory network analysis.
State Key Laboratory of Plant Physiology and Biochemistry, Engineering Research Center of Plant Growth Regulator, Ministry of Education & College of Agronomy and Biotechnology, China Agricultural University, No.2 Yuanmingyuan West Road, Haidian, Beijing 100193, China.; North China Key Laboratory for Crop Germplasm Resources, Ministry of Education, State Key Laboratory of North China Crop Improvement and Regulation & College of Agronomy, Hebei Agricultural University, Baoding, Hebei 071001, China.; College of Plant Science and Technology, Beijing University of Agriculture, Beijing, 102206, China.
Basal internode length is important for lodging resistance of maize (Zea mays L.). In this study, foliar application of coronatine (COR) at the V8 stage differentially suppressed the length of the eighth internode of 10 cultivars, and three, five, and two cultivars were demonstrated to have strong (SC), moderate (MC), and weak (WC) degrees of internode shortening, respectively. RNA-Seq of the eighth internode of these cultivars revealed a total of 7895 internode elongation-regulating genes (IEGs, including 777 transcription factors (TFs)). Compared with those in WC, the hormone-related genes of cytokinin (CTK), gibberellin (GA), auxin and ethylene (ET) genes in SC were significantly downregulated, and more cell cycle regulatory factors and cell wall related genes showed significant changes, which severely inhibited internode elongation. Furthermore, we explored the direct regulatory relationship between two important TFs and target genes using EMSA, ZmABI7 and ZmMYB117, which regulate the cell cycle and cell wall modification by directly binding to the promoters of ZmCYC1, ZmCYC3, ZmCYC7, and ZmCPP1. The landscape transcriptome atlas reported herein provides a useful resource for studying maize internode development, which may provide a genetic basis for targeted control of internode length to improve lodging tolerance of maize.
PMID: 37170764
J Exp Bot , IF:6.992 , 2023 May doi: 10.1093/jxb/erad174
Auxin as an architect of the pectin matrix.
Umea Plant Science Centre, Department of Forest Genetics and Plant Physiology, Swedish University of Agricultural Sciences (SLU), 90183, Umea, Sweden.; CRRBM, Universite de Picardie Jules Verne, 80000, Amiens, France.
Auxin is a versatile plant growth regulator that triggers multiple signalling pathways at different spatial and temporal resolutions. A plant cell is surrounded by the cell wall, a complex and dynamic network of polysaccharides. The cell wall needs to be rigid to provide mechanical support and protection and highly flexible to allow cell growth and shape acquisition. The modification of the pectin components, among other processes, is a mechanism by which auxin activity alters the mechanical properties of the cell wall. Auxin signalling precisely controls the transcriptional output of several pectin remodelling enzyme-encoded genes, their local activity and pectin deposition and modulation in different developmental contexts. This review examines the mechanism of auxin activity in regulating pectin chemistry at organ, cellular and subcellular levels across diverse plant species and asks questions that remain to be addressed to fully understand the interplay between auxin and pectin in plant growth and development.
PMID: 37166384
J Exp Bot , IF:6.992 , 2023 May doi: 10.1093/jxb/erad166
Loss of S-Nitrosoglutathione reductase disturbs phytohormone homeostasis and regulates shoot side branching and fruit growth in tomato.
Departamento de Botanica, Instituto de Biociencias, Universidade de Sao Paulo, 05508-900, Sao Paulo, SP, Brazil.; Departamento de Biologia Vegetal, Universidade Federal de Vicosa, 36570-900, Vicosa, MG, Brazil.; Departamento de Genetica e Biologia Evolutiva, Instituto de Biociencias, Universidade de Sao Paulo, 05508-900, Sao Paulo, SP, Brazil.; Department of Biochemistry, Cell and Molecular Biology of Plants, Estacion Experimental del Zaidin, Spanish National Research Council (CSIC), Granada, Spain.; Departamento de Ciencias Biologicas, Escola Superior de Agricultura Luiz de Queiroz, Universidade de Sao Paulo, 13418-900, Piracicaba, SP, Brazil.
S-nitrosoglutathione (GSNO) plays a central role in nitric oxide (NO) homeostasis, and GSNO reductase (GSNOR) regulates the cellular levels of GSNO across kingdoms. Here, we investigated the role of endogenous NO in shaping shoot architecture and controlling fruit set and growth in tomato (Solanum lycopersicum). SlGSNOR silencing promoted shoot side branching and led to reduced fruit size, negatively impacting fruit yield. Greatly intensified in slgsnor knockout plants, these phenotypical changes were virtually unaffected by SlGSNOR overexpression. SlGSNOR silencing or knockout intensified protein tyrosine nitration and S-nitrosation and led to aberrant auxin production and signaling in leaf primordia and fruit-setting ovaries, besides restricting the shoot basipetal polar auxin transport stream. SlGSNOR deficiency triggered extensive transcriptional reprogramming at early fruit development, reducing pericarp cell proliferation due to restrictions on auxin, gibberellin and cytokinin production and signaling. Abnormal chloroplast development and carbon metabolism were also detected in early-developing NO-overaccumulating fruits, possibly limiting energy supply and building blocks for fruit growth. These findings provide new insights into the mechanisms by which endogenous NO fine-tunes the delicate hormonal network controlling shoot architecture, fruit set and post-anthesis fruit development, emphasizing the relevance of NO-auxin interaction for plant development and productivity.
PMID: 37157899
J Exp Bot , IF:6.992 , 2023 May doi: 10.1093/jxb/erad168
"The phenomenon of autonomous endosperm in sexual and apomictic plants".
Department of Plant Cytology and Embryology, Faculty of Biology, University of Gdansk, Gdansk, Poland.; School of Plant Sciences and Food Security, Tel Aviv University, Tel Aviv, Israel.
Endosperm is a key nutritive tissue that supports the developing embryo or seedling, and serves as a major nutritional source for human and livestock feed. In sexual flowering plants, it generally develops after fertilization. However, autonomous endosperm (AE) formation (i.e., independently from fertilization) is also possible. Recent findings of AE loci/ genes and aberrant imprinting in native apomicts, together with a successful initiation of parthenogenesis in rice and lettuce, have enhanced our understanding of the mechanisms bridging sexual and apomictic seed formation. However, the mechanisms driving AE development are not well understood. This review presents novel aspects related to AE development in sexual and asexual plants underlying stress conditions as the primary trigger for AE. Both, application of hormones to unfertilized ovules and mutations that impair epigenetic regulation lead to AE development in sexual Arabidopsis thaliana, which may point to a common pathway for both phenomena. Apomictic-like AE development under experimental conditions can take place due to auxin-dependent gene expression and/or DNA methylation.
PMID: 37155961
J Exp Bot , IF:6.992 , 2023 May doi: 10.1093/jxb/erad163
Local phytochrome signalling limits root growth in light by repressing auxin biosynthesis.
Plant Developmental Genetics, Institute of Biology Leiden, Leiden University, Sylviusweg 72, 2333 BE, Leiden, Netherlands.
In nature, plant shoots are exposed to light whereas the roots grow in relative darkness. Surprisingly, many root studies rely on in vitro systems that leave the roots exposed to light whilst ignoring the possible effects of this light on root development. Here, we investigated how direct root illumination affects root growth and development in Arabidopsis and tomato. Our results show that in light-grown Arabidopsis roots activation of local phytochrome A and B by far-red or red light inhibits respectively PHYTOCHROME INTERACTING FACTORs 1 or 4, resulting in decreased YUCCA4 and YUCCA6 expression. As a result, auxin levels in the root apex become suboptimal, ultimately resulting in reduced growth of light-grown roots. These findings highlight once more the importance of using in vitro systems where roots are grown in darkness, for studies that focus on root system architecture. Moreover, we show that the response and components of this mechanism are conserved in tomato roots, thus signifying its importance for horticulture as well. Our findings open up new research possibilities to investigate the importance of light-induced root growth inhibition for plant development, possibly by exploring putative correlations with responses to other abiotic signals, such as temperature, gravity, touch, or salt stress.
PMID: 37140032
J Exp Bot , IF:6.992 , 2023 Apr doi: 10.1093/jxb/erad159
Cytokinin-inducible response regulator SlRR6 regulates plant height through gibberellin and auxin pathways in tomato.
Department of Horticulture, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou 310058, China.; Institute of Vegetable Science, Zhejiang Academy of Agricultural Sciences, Hangzhou 310022, China.; Key Laboratory of Horticultural Plant Growth, Development and Quality Improvement, Ministry of Agricultural, Zhejiang University, Hangzhou 310058, China.
Plant height is a key agronomic trait regulated by several phytohormones like gibberellins (GAs) and auxin. However, little is known about how cytokinin (CK) participates in this process. Here, we report that SlRR6, a type-A response regulator in CK signaling pathway, positively regulates plant height in tomato. SlRR6 was induced by exogenous kinetin and GA3, but inhibited by indole-3-acetic acid (IAA). Knockout of SlRR6 reduced tomato plant height through shortening internode length, while overexpression of SlRR6 caused higher plant due to increased internode number. Cytological observation of longitudinal stems showed that both knockout and overexpression of SlRR6 generated larger cells, but significantly reduced cell numbers in each internode. Further studies demonstrated that overexpression of SlRR6 enhanced GA accumulation and lowered IAA content, along with expression changes in GA- and IAA-related genes. Exogenous paclobutrazol and IAA treatments restored the increased plant height phenotype in SlRR6-overexpressing lines. Yeast two-hybrid, bimolecular fluorescence complementation and co-immunoprecipitation assays showed that SlRR6 interacts with a small auxin up RNA protein SlSAUR58. Moreover, SlSAUR58-overexpressing plants were dwarf with decreased internode length. Overall, our findings establish SlRR6 as a vital component in the CK signaling, GA, and IAA regulatory network that controls plant height.
PMID: 37115725
J Exp Bot , IF:6.992 , 2023 Apr doi: 10.1093/jxb/erad152
GhTCP7 suppresses petal expansion by interacting with the WIP-type zinc finger protein GhWIP2 in Gerbera hybrida.
State Key Laboratory of Conservation and Utilization of Bio-Resources and Center for Life Science, School of Life Sciences, Yunnan University, Kunming, Yunnan 650091, China.; Key Laboratory of Southern Subtropical Plant Diversity, Fairy Lake Botanical Garden, Shenzhen & Chinese Academy of Sciences, Shenzhen, Guangdong 518004, China.; Department of Plant and Soil Sciences, Kentucky Tobacco Research and Development Center, University of Kentucky, Lexington, KY 40546, USA.; Institute of Biomass Engineering; Key Laboratory of Energy Plants Resource and Utilization, Ministry of Agriculture and Rural Affairs; Guangdong Engineering Technology Research Center of Agricultural and Forestry Biomass, South China Agricultural University, Guangzhou 510642, China.; Provincial Key Lab of Biotechnology for Plant Development, School of Life Sciences, South China Normal University, Guangzhou, Guangdong 510631, China.
Petal size is for a critical factor in plant reproduction and horticulture, and is largely determined by cell expansion. Gerbera hybrida is an important horticultural plant and serves as a model for studying petal organogenesis. We have previously characterized GhWIP2, a WIP-type zinc protein, that constrains petal size by suppressing cell expansion. However, the molecular mechanism remained largely unclear. Using yeast two-hybrid screening, bimolecular fluorescence complementation, and coimmunoprecipitation, we identified a TEOSINTE BRANCHED1/CYCLOIDEA/PROLIFERATING CELL FACTOR (TCP) family transcription factor (TF), GhTCP7, that interacts with GhWIP2 both in vitro and in vivo. Using reverse genetic approaches, we elucidated the function of the GhTCP7-GhWIP2 complex in controlling petal expansion. GhTCP7 overexpression (GhTCP7-OE) severely reduced cell expansion and petal size, whereas GhTCP7 silencing resulted in increased cell expansion and petal size. GhTCP7 showed similar expression patterns to GhWIP2 in various types of G. hybrida petals. We further identified GhIAA26, which encodes an auxin signaling regulator, that is activated by the GhTCP7-GhWIP2 complex, leading to the suppression of petal expansion. Our findings reveal a previously unknown transcriptional regulatory mechanism that involves protein-protein interactions between two different TF families to activate a negative regulator of petal organogenesis.
PMID: 37102769
J Exp Bot , IF:6.992 , 2023 Apr doi: 10.1093/jxb/erad137
Learnings from a century of apical dominance research.
ARC Centre of Excellence for Plant Success in Nature and Agriculture, St Lucia, QLD 4072, Australia.; School of Biological Sciences, The University of Queensland, St Lucia, QLD 4072, Australia.; Universite Paris-Saclay, INRAE, AgroParisTech, Institut Jean-Pierre Bourgin (IJPB), 78000, Versailles, France.
The process of apical dominance by which the apical bud/shoot tip of the plant inhibits the outgrowth of axillary buds located below has been studied for more than a century. Different approaches were used over time with first the physiology era, the genetic era, and then the multidisciplinary era. During the physiology era, auxin was thought of as the master regulator of apical dominance acting indirectly to inhibit bud outgrowth via unknown secondary messenger(s). Potential candidates were cytokinin (CK) and abscisic acid (ABA). The genetic era with the screening of shoot branching mutants in different species revealed the existence of a novel carotenoid-derived branching inhibitor and led to the significant discovery of strigolactones (SLs) as a novel class of plant hormones. The re-discovery of the major role of sugars in apical dominance emerged from modern physiology experiments and involves ongoing work with genetic material affected in sugar-signalling. As crops and natural selection rely on the emergent properties of networks such as this branching network, future work should explore the whole network, the details of which are critical but not individually sufficient to solve the wicked problems of sustainable food supply and climate change.
PMID: 37076257
J Exp Bot , IF:6.992 , 2023 Apr doi: 10.1093/jxb/erad132
A matter of time: auxin signaling dynamics and the regulation of auxin responses during plant development.
Laboratoire Reproduction et Developpement des Plantes, Univ Lyon, ENS de Lyon, CNRS, INRAE, F-69342, Lyon, France.
As auxin is a major regulator of plant development, studying the signaling mechanisms by which auxin influences cellular activities is of primary importance. In this review, we describe the current knowledge on the different modalities of signaling, from the well-characterized canonical nuclear auxin pathway, to the more recently discovered or re-discovered non-canonical modes of auxin signaling. In particular, we discuss how both the modularity of the nuclear auxin pathway and the dynamic regulation of its core components allow to trigger specific transcriptomic responses. We highlight the fact that the diversity of modes of auxin signaling allows for a wide range of timescales of auxin responses, from second-scale cytoplasmic responses to minute/hour-scale modifications of gene expression. Finally, we question the extent to which the temporality of auxin signaling and responses contributes to development in both the shoot and the root meristems. We conclude by stressing the fact that future investigations should allow to build an integrative view not only of the spatial control, but also of the temporality of auxin-mediated regulation of plant development, from the cell to the whole organism.
PMID: 37042516
J Exp Bot , IF:6.992 , 2023 Apr doi: 10.1093/jxb/erad131
The dynamics of Arabidopsis H2A.Z on SMALL AUXIN UP RNAs regulates abscisic acid-auxin signaling crosstalk.
Joint Center for Single Cell Biology, School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai 200240, 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; University of Chinese Academy of Sciences, Shanghai 200032, China.
Extreme environmental changes threaten plant survival and worldwide food production. In response to osmotic stresses, plant hormone ABA activates stress responses and restricts plant growth. However, the epigenetic regulation of the ABA signaling and ABA-auxin crosstalk are not well known. Here we report that the histone variant H2A.Z knockdown mutant in Arabidopsis Col-0 ecotype, h2a.z-kd, has altered ABA signaling and stress performances. RNA-sequencing data showed that a majority of stress related genes are activated in h2a.z-kd. In addition, we revealed that ABA directly promotes the deposition of H2A.Z on SMALL AUXIN UP RNAs (SAURs), which is involved in ABA-repressed SAUR expression. Moreover, we found that ABA represses the transcription of H2A.Z genes through suppressing ARF7/19-HB22/25 module. Our results shed light on a dynamic and reciprocal regulation hub through H2A.Z deposition on SAURs and ARF7/19-HB22/25-mediated H2A.Z transcription to integrate ABA/auxin signaling and regulate stress responses in Arabidopsis.
PMID: 37022978
J Exp Bot , IF:6.992 , 2023 Apr doi: 10.1093/jxb/erad123
GOLVEN peptides regulate lateral root spacing as part of a negative feedback loop on the establishment of auxin maxima.
Department of Plant Biotechnology and Bioinformatics, Faculty of Sciences, Ghent University, Ghent 9052, Belgium.; Center for Plant Systems Biology, VIB-UGent, Ghent 9052, Belgium.; Department of Plants and Crops, Faculty of Bioscience Engineering, Ghent University, Ghent 9000, Belgium.; Department of Forest Genetics and Plant Physiology, Umea Plant Science Centre, Swedish University of Agricultural Sciences, 90183 Umea, Sweden.
Lateral root initiation requires the accumulation of auxin in lateral root founder cells, yielding a local auxin maximum. The positioning of auxin maxima along the primary root determines the density and spacing of lateral roots. The GOLVEN6 (GLV6) and GLV10 signaling peptides and their receptors have been established as regulators of lateral root spacing via their inhibitory effect on lateral root initiation in Arabidopsis. However, it remained unclear how these GLV peptides interfere with auxin signaling or homeostasis. Here, we show that GLV6/10 signaling regulates the expression of a subset of auxin response genes, downstream of the canonical auxin signaling pathway, while simultaneously inhibiting the establishment of auxin maxima within xylem-pole pericycle cells that neighbor lateral root initiation sites. We present genetic evidence that this inhibitory effect relies on the activity of the PIN3 and PIN7 auxin export proteins. Furthermore, GLV6/10 peptide signaling was found to enhance PIN7 abundance in the plasma membranes of xylem-pole pericycle cells, which likely stimulates auxin efflux from these cells. Based on these findings, we propose a model in which the GLV6/10 signaling pathway serves as a negative feedback mechanism that contributes to the robust patterning of auxin maxima along the primary root.
PMID: 37004244
J Exp Bot , IF:6.992 , 2023 May , V74 (10) : P3122-3141 doi: 10.1093/jxb/erad094
Maize WRKY28 interacts with the DELLA protein D8 to affect skotomorphogenesis and participates in the regulation of shade avoidance and plant architecture.
State Key Laboratory of Plant Environmental Resilience, College of Biological Sciences, China Agricultural University, Beijing 100193, China.; Center for Crop Functional Genomics and Molecular Breeding, China Agricultural University, Beijing 100193, China.
Competition for light from neighboring vegetation can trigger the shade-avoidance response (SAR) in plants, which is detrimental to their yield. The molecular mechanisms regulating SAR are well established in Arabidopsis, and some regulators of skotomorphogenesis have been found to be involved in the regulation of the SAR and plant architecture. However, the role of WRKY transcription factors in this process has rarely been reported, especially in maize (Zea mays). Here, we report that maize Zmwrky28 mutants exhibit shorter mesocotyls in etiolated seedlings. Molecular and biochemical analyses demonstrate that ZmWRKY28 directly binds to the promoter regions of the Small Auxin Up RNA (SAUR) gene ZmSAUR54 and the Phytochrome-Interacting Factor (PIF) gene ZmPIF4.1 to activate their expression. In addition, the maize DELLA protein Dwarf Plant8 (D8) interacts with ZmWRKY28 in the nucleus to inhibit its transcriptional activation activity. We also show that ZmWRKY28 participates in the regulation of the SAR, plant height, and leaf rolling and erectness in maize. Taken together, our results reveal that ZmWRKY28 is involved in GA-mediated skotomorphogenic development and can be used as a potential target to regulate SAR for breeding of high-density-tolerant cultivars.
PMID: 36884355
J Exp Bot , IF:6.992 , 2023 May , V74 (10) : P3047-3059 doi: 10.1093/jxb/erad058
The NIN-LIKE PROTEIN 7 transcription factor modulates auxin pathways to regulate root cap development in Arabidopsis.
Department of Botany and Plant Pathology and Center for Plant Biology, Purdue University, 915 W. State Street, West Lafayette, IN 47907, USA.
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 relatively stable in size and must integrate endogenous developmental pathways with environmental signals, yet the mechanism is not clear. We previously showed that low pH conditions altered 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 in Arabidopsis NLP7 integrates nitrate signaling with auxin pathways to regulate root cap development. We found that low nitrate conditions promote aberrant release of root cap cells. 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 Apr , V74 (8) : P2542-2555 doi: 10.1093/jxb/erad051
The wheat basic helix-loop-helix gene TabHLH123 positively modulates the formation of crown roots and is associated with plant height and 1000-grain weight 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 underlying their formation in wheat (Triticum aestivum) have not been fully elucidated. In this study, we identified a wheat basic helix-loop-helix (bHLH) protein, TabHLH123, that interacts with the essential regulator of crown root initiation, MORE ROOT in wheat (TaMOR). TabHLH123 is expressed highly in shoot bases and roots. Ectopic expression of TabHLH123 in rice resulted in more roots compared with the wild type. TabHLH123 regulates the expression of genes controlling crown-root development and auxin metabolism, responses, and transport. In addition, we analysed the nucleotide sequence polymorphisms of TabHLH123s in the wheat genome and identified a superior haplotype, TabHLH123-6B, that is associated with high root dry weight and 1000-grain weight, and short plant height. Our study reveals the role of TabHLH123 in controlling the formation of crown roots and provides beneficial insights for molecular marker-assisted breeding in wheat.
PMID: 36749713
J Exp Bot , IF:6.992 , 2023 Apr , V74 (8) : P2448-2461 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 LS2 9JT, UK.; 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 overcoming 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
Int J Biol Macromol , IF:6.953 , 2023 May , V237 : P124061 doi: 10.1016/j.ijbiomac.2023.124061
Small Auxin Up RNA (SAUR) gene family identification and functional genes exploration during the floral organ and fruit developmental stages in pineapple (Ananas comosus L.) and its response to salinity and drought stresses.
College of Life Science, Fujian Provincial Key Laboratory of Haixia Applied Plant Systems Biology, Fujian Agriculture and Forestry University, Fuzhou 350002, China.; Guangxi Key Laboratory of Sugarcane Biology, State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, College of Agriculture, Guangxi University, Nanning 530004, China.; Fishery Multiplication Management Station of Lijiang River Water Supply Hub Project, Guilin 541001, China.; College of Life Science, Fujian Provincial Key Laboratory of Haixia Applied Plant Systems Biology, Fujian Agriculture and Forestry University, Fuzhou 350002, China; Guangxi Key Laboratory of Sugarcane Biology, State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, College of Agriculture, Guangxi University, Nanning 530004, China; Pingtan Science and Technology Research Institute of Fujian Agriculture and Forestry University, Pingtan 350400, China. Electronic address: yuanqin@fafu.edu.cn.; College of Life Science, Fujian Provincial Key Laboratory of Haixia Applied Plant Systems Biology, Fujian Agriculture and Forestry University, Fuzhou 350002, China; Guangxi Key Laboratory of Sugarcane Biology, State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, College of Agriculture, Guangxi University, Nanning 530004, China. Electronic address: xpniu0613@126.com.
In plants, sexual reproduction relies on the proper development of floral organs that facilitate the successful development of fruits and seeds. Auxin responsive small auxin-up RNA (SAUR) genes play essential roles in floral organ formation and fruit development. However, little is known about the role of SAUR genes in pineapple floral organ formation and fruit development as well as stress responses. In this study, based on genome information and transcriptome datasets, 52 AcoSAUR genes were identified and grouped into 12 groups. The gene structure analysis revealed that most AcoSAUR genes did not have introns, although auxin-acting elements were abundant in the promoter region of AcoSAUR members. The expression analysis across the multiple flower and fruit development stages revealed differential expression of AcoSAUR genes, indicating a tissue and stage-specific function of AcoSAURs. Correlation analysis and pairwise comparisons between gene expression and tissue specificity identified stamen-, petal-, ovule-, and fruit-specific AcoSAURs involved in pineapple floral organs (AcoSAUR4/5/15/17/19) and fruit development (AcoSAUR6/11/36/50). RT-qPCR analysis revealed that AcoSAUR12/24/50 played positive roles in response to the salinity and drought treatment. This work provides an abundant genomic resource for functional analysis of AcoSAUR genes during the pineapple floral organs and fruit development stages. It also highlights the role of auxin signaling involved in pineapple reproductive organ growth.
PMID: 36933586
Int J Biol Macromol , IF:6.953 , 2023 Apr , 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 , 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
Development , IF:6.868 , 2023 May , V150 (9) doi: 10.1242/dev.201485
Microbial pattern recognition suppresses de novo organogenesis.
Department of Plant Pathology, College of Agricultural and Environmental Sciences, University of Georgia, Athens, GA 30602, USA.
De novo root regeneration (DNRR) is a developmental process that regenerates adventitious roots from wounded tissues. Phytohormone signaling pathways involved in microbial resistance are mobilized after cutting and influence de novo root regeneration. Microbes may positively or negatively influence the development and stress responses of a plant. However, most studies on the molecular mechanisms of de novo organogenesis are performed in aseptic conditions. Thus, the potential crosstalk between organ regeneration and biotic stresses is underexplored. Here, we report the development of a versatile experimental system to study the impact of microbes on DNRR. Using this system, we found that bacteria inhibited root regeneration by activation of, but not limited to, pathogen-associated molecular pattern (PAMP)-triggered immunity. Sensing bacteria-derived flagellin 22 peptide (flg22) inhibited root regeneration by interfering with the formation of an auxin maximum at the wound site. This inhibition relies on the receptor complex that recognizes microbial patterns but may bypass the requirement of salicylic acid signaling.
PMID: 37073949
Development , IF:6.868 , 2023 May , V150 (9) doi: 10.1242/dev.201635
A cornichon protein controls polar localization of the PINA auxin transporter in Physcomitrium patens.
Departamento de Biologia Molecular de Plantas, Instituto de Biotecnologia, Universidad Nacional Autonoma de Mexico, Av. Universidad 2001, Cuernavaca, Morelos 62210, Mexico.; Department of Biological Sciences, Dartmouth, Hanover, NH 03755, USA.
Newly synthesized membrane proteins pass through the secretory pathway, starting at the endoplasmic reticulum and packaged into COPII vesicles, to continue to the Golgi apparatus before reaching their membrane of residence. It is known that cargo receptor proteins form part of the COPII complex and play a role in the recruitment of cargo proteins for their subsequent transport through the secretory pathway. The role of cornichon proteins is conserved from yeast to vertebrates, but it is poorly characterized in plants. Here, we studied the role of the two cornichon homologs in the secretory pathway of the moss Physcomitrium patens. Mutant analyses revealed that cornichon genes regulate different growth processes during the moss life cycle by controlling auxin transport, with CNIH2 functioning as a specific cargo receptor for the auxin efflux carrier PINA, with the C terminus of the receptor regulating the interaction, trafficking and membrane localization of PINA.
PMID: 37052186
J Environ Manage , IF:6.789 , 2023 Jul , V337 : P117723 doi: 10.1016/j.jenvman.2023.117723
Integrated biochemical and transcriptomic analysis reveals the effects of Burkholderia sp. SRB-1 on cadmium accumulating in Chrysopogon zizanioides L. under Cd stress.
Key Laboratory of Bio-resource and Eco-Environment of Ministry of Education, College of Life Sciences, Sichuan University, Chengdu, 610065, Sichuan, PR China.; College of Pharmacy, Chengdu Medical College, Chengdu, Sichuan, China.; Soil and Fertilizer Institute, Sichuan Academy of Agricultural Sciences, Chengdu, 610066, China.; Key Laboratory of Bio-resource and Eco-Environment of Ministry of Education, College of Life Sciences, Sichuan University, Chengdu, 610065, Sichuan, PR China; Key Laboratory of Environment Protection, Soil Ecological Protection and Pollution Control, Sichuan University & Department of Ecology and Environment of Sichuan, Chengdu, 610065, Sichuan, PR China. Electronic address: xuheng64@sina.com.
Application of plant growth-promoting rhizobacteria plays a vital role in enhancing phytoremediation efficiency. In this study, multiple approaches were employed to investigate the underlying mechanisms of Burkholderia sp. SRB-1 (SRB-1) on elevating Cd uptake and accumulation. Inoculation experiment indicated that SRB-1 could facilitate plant growth and Cd tolerance, as evidenced by the enhanced plant biomass and antioxidative enzymes activities. Cd content in plant shoots and roots increased about 36.56%-39.66% and 25.97%-130.47% assisted with SRB-1 when compared with control. Transcriptomics analysis revealed that SRB-1 upregulated expression of amiE, AAO1-2 and GA2-ox related to auxin and gibberellin biosynthesis in roots. Auxin and gibberellin, as hormone signals, regulated plant Cd tolerance and growth through activating hormone signal transduction pathways, which might also contribute to 67.94% increase of dry weight. The higher expression levels of ATP-binding cassette transporter subfamilies (ABCB, ABCC, ABCD and ABCG) in Chrysopogon zizanioides roots contributed to higher Cd uptake in Cd15 B (323.83 mg kg(-1)) than Cd15 (136.28 mg kg(-1)). Further, SRB-1 facilitated Cd migration from roots to shoots via upregulating the expression of Nramp, ZIP and HMA families. Our integrative analysis provided a molecular-scale perspective on Burkholderia sp. SRB-1 contributing to C. zizanioides performance.
PMID: 36958280
Anal Chim Acta , IF:6.558 , 2023 May , V1256 : P341158 doi: 10.1016/j.aca.2023.341158
Vibration for enhancement of electrochemical analysis of biomolecules in a droplet on the rough surface of a disposable working electrode.
School of Public Health, Nantong University, 9 Seyuan Rd., Nantong, Jiangsu, 226019, 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.; 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. Electronic address: liuwu@cemps.ac.cn.; School of Public Health, Nantong University, 9 Seyuan Rd., Nantong, Jiangsu, 226019, China. Electronic address: zhugexk@ntu.edu.cn.; School of Public Health, Nantong University, 9 Seyuan Rd., Nantong, Jiangsu, 226019, China. Electronic address: hxl362349@ntu.edu.cn.; School of Public Health, Nantong University, 9 Seyuan Rd., Nantong, Jiangsu, 226019, China. Electronic address: ningbao@ntu.edu.cn.
Although electrochemical detection of microliters-level solutions is attractive for analysis of low-amount biological samples, its performance could be weakened by limited mass transfer due to low Reynolds number and laminar flow. Herein we designed a 3D-printed electroanalytical device to apply vibration for improvement of mass transfer during electrochemical detection. In our approach, the droplet-size sample solution containing Indole-3-acetic acid (IAA, as a model) was directly applied on the effective surface of a disposable working electrode. We demonstrated that vibration could enhance electrochemical responses of IAA more on the rough surface than on the smooth surface of the working electrodes. After optimization, the sensitivity for electrochemical detection of a 20-muL droplet under vibration with the voltage of 7 V increased more than 100% compared with the static condition. The enhanced electrochemical responses brought by vibration could be achieved reproducibly, which could be ascribed to improved mass transfer. Our strategy could be practically applied for differentiation of IAA in different tissues of Marchantia polymorpha with enhanced responses. This study suggested that vibration might become a simple and effective method to improve mass transfer in analysis of microliter-volume solutions, which might be extended for more biochemical assays.
PMID: 37037634
Ying Yong Sheng Tai Xue Bao , IF:6.528 , 2023 May , V34 (5) : P1263-1271 doi: 10.13287/j.1001-9332.202305.013
Effects of 5-HT on the cold resistance of mangrove Kandelia obovata seedlings.
College of Life and Environment Science, Wenzhou University, Wenzhou 325035, Zhejiang, China.; School of Design and Digital Arts, Zhejiang Industry and Trade Vocational College, Wenzhou 325000, Zhejiang, China.; Key Laboratory of Exploitation and Preservation of Coastal Bio-resource, Zhejiang Mariculture Research Institute, Wenzhou 325005, Zhejiang, China.
5-hydroxytryptamine (5-HT) participates in plant growth and development, and can also delay senescence and cope with abiotic stress. To explore the role of 5-HT in regulating the abilities of mangrove in cold resis-tance, we examined the effects of cold acclimation and the spraying of p-chlorophenylalanine (p-CPA, 5-HT synthesis inhibitor) on leaf gas exchange parameters and CO(2) response curves (A/Ca), as well as the endogenous phytohormone content levels in the mangrove species Kandelia obovata seedlings under low temperature stress. The results showed that low temperature stress significantly reduced the contents of 5-HT, chlorophyll, endogenous auxin (IAA), gibberellin (GA), and abscisic acid (ABA). It weakened the CO(2) utilization abilities of plants and reduced net photosynthetic rate, which ultimately reduced carboxylation efficiency (CE). Under low temperature stress, exogenous p-CPA reduced the contents of photosynthetic pigments, endogenous hormones, and 5-HT in the leaves, which aggravated the damages caused by low temperature stress on photosynthesis. By enhancing cold acclimation abilities, the endogenous IAA content in the leaves could was reduced under low temperature stress, promoted the production of 5-HT, improved the contents of photosynthetic pigments, GA, and ABA, as well as enhanced photosynthetic carbon assimilation abilities, which would increase photosynthesis in the K. obovata seedlings. Under cold acclimation conditions, the spraying of p-CPA could significantly inhibit the synthesis of 5-HT, promote the production of IAA, and reduce the contents of photosynthetic pigments, GA, ABA, and CE, which would weaken the effects of cold acclimation by improving the cold resistance of mangroves. In conclusion, cold acclimation could improve the cold resistance abilities of K. obovata seedlings by regulating photosynthetic carbon assimilation capacity and the contents of endogenous phytohormone. 5-HT synthesis is one of the necessary conditions for improving the cold resistance abilities of mangroves.
PMID: 37236943
Environ Res , IF:6.498 , 2023 Jul , V229 : P115966 doi: 10.1016/j.envres.2023.115966
Strigolactones can be a potential tool to fight environmental stresses in arid lands.
Xinjiang Key Desert Plant Roots Ecology and Vegetation Restoration Laboratory, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, China; State Key Laboratory of Desert and Oasis Ecology, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi, China; Cele National Station of Observation and Research for Desert-Grassland Ecosystems, Cele, 848300, China. Electronic address: akash.malik786@mails.ucas.ac.cn.; Department of Plant Breeding & Genetics, Gomal University, Dera Ismail Khan, Pakistan.; CSIC, Global Ecology Unit, CREAF-CSIC-UAB, Bellaterra, 08193, Barcelona, Catalonia, Spain; CREAF, Cerdanyola Del Valles, 08193, Catalonia, Spain.; Instituto de Fisiologia Vegetal, Consejo Nacional de Investigaciones Cientificas y Tecnicas, Universidad Nacional de La Plata, Buenos Aires, Argentina.; Department of Botanical and Environmental Sciences, Faculty of Biological Sciences, Kohat University of Science and Technology, Kohat, Pakistan.; Xinjiang Key Desert Plant Roots Ecology and Vegetation Restoration Laboratory, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, China; State Key Laboratory of Desert and Oasis Ecology, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi, China; Cele National Station of Observation and Research for Desert-Grassland Ecosystems, Cele, 848300, China.; Xinjiang Key Desert Plant Roots Ecology and Vegetation Restoration Laboratory, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, China; State Key Laboratory of Desert and Oasis Ecology, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi, China; Cele National Station of Observation and Research for Desert-Grassland Ecosystems, Cele, 848300, China. Electronic address: zengfj@ms.xjb.ac.cn.; Key Laboratory of Humid Subtropical Eco-Geographical Process, Ministry of Education, Fujian Normal University, Fuzhou, 350007, China; Institute of Geography, Fujian Normal University, Fuzhou, 350007, China.; Department of Biology, College of Science, University of Tabuk, Tabuk, Saudi Arabia.; State Key Laboratory of Desert and Oasis Ecology, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi, China.; State Key Laboratory of Phytochemistry and Plant Resources in West China, Yunnan Key Laboratory of Natural Medicinal Chemistry, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, 650201, China.
BACKGROUND: Environmental stresses pose a significant threat to plant growth and ecosystem productivity, particularly in arid lands that are more susceptible to climate change. Strigolactones (SLs), carotenoid-derived plant hormones, have emerged as a potential tool for mitigating environmental stresses. METHODS: This review aimed to gather information on SLs' role in enhancing plant tolerance to ecological stresses and their possible use in improving the resistance mechanisms of arid land plant species to intense aridity in the face of climate change. RESULTS: Roots exude SLs under different environmental stresses, including macronutrient deficiency, especially phosphorus (P), which facilitates a symbiotic association with arbuscular mycorrhiza fungi (AMF). SLs, in association with AMF, improve root system architecture, nutrient acquisition, water uptake, stomatal conductance, antioxidant mechanisms, morphological traits, and overall stress tolerance in plants. Transcriptomic analysis revealed that SL-mediated acclimatization to abiotic stresses involves multiple hormonal pathways, including abscisic acid (ABA), cytokinins (CK), gibberellic acid (GA), and auxin. However, most of the experiments have been conducted on crops, and little attention has been paid to the dominant vegetation in arid lands that plays a crucial role in reducing soil erosion, desertification, and land degradation. All the environmental gradients (nutrient starvation, drought, salinity, and temperature) that trigger SL biosynthesis/exudation prevail in arid regions. The above-mentioned functions of SLs can potentially be used to improve vegetation restoration and sustainable agriculture. CONCLUSIONS: Present review concluded that knowledge on SL-mediated tolerance in plants is developed, but still in-depth research is needed on downstream signaling components in plants, SL molecular mechanisms and physiological interactions, efficient methods of synthetic SLs production, and their effective application in field conditions. This review also invites researchers to explore the possible application of SLs in improving the survival rate of indigenous vegetation in arid lands, which can potentially help combat land degradation problems.
PMID: 37100368
Plant J , IF:6.417 , 2023 May doi: 10.1111/tpj.16333
Auxin biosynthesis gene FveYUC4 is critical for leaf and flower morphogenesis in woodland strawberry.
National Key Laboratory for Germplasm Innovation & Utilization of Horticultural Crops, 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.
Auxin plays an essential role in plant growth and development, particularly in fruit development. The YUCCA (YUC) genes encode flavin monooxygenases that catalyze a rate-limiting step in auxin biosynthesis. Mutations that disrupt YUC gene function provide useful tools for dissecting general and specific functions of auxin during plant development. In woodland strawberry (Fragaria vesca), two EMS mutants, Y422 and Y1011, have been identified that exhibit severe defects in leaves and flowers. In particular, the width of the leaf blade is greatly reduced and each leaflet in the mutants has fewer and deeper serrations. In addition, the number and shape of the floral organs are altered, resulting in smaller fruits. Mapping by sequencing revealed that both mutations reside in the FveYUC4 gene and were therefore renamed as yuc4-1 and yuc4-2. Consistent with a role for FveYUC4 in auxin synthesis, free auxin and its metabolites are significantly reduced in the yuc4 leaves and flowers. This role of FveYUC4 in leaf and flower development is supported by its high and specific expression in young leaves and flower buds using GUS reporters. Furthermore, germline transformation of pYUC4::YUC4, which resulted in elevated expression of FveYUC4 in yuc4 mutants, not only rescued the leaf and flower defects but also produced parthenocarpic fruits. Taken together, our data demonstrate that FveYUC4 is essential for leaf and flower morphogenesis in woodland strawberry by providing auxin hormone at the proper time and in the right tissues.
PMID: 37248638
Plant J , IF:6.417 , 2023 May doi: 10.1111/tpj.16330
A very long chain fatty acid responsive transcription factor, MYB93, regulates lateral root development in Arabidopsis.
Faculty of Agriculture, Meijo University, 1-501 Shiogamaguchi, Tempaku-ku, Nagoya, Aichi, 468-8502, Japan.; Department of Biological Chemistry, College of Bioscience and Biotechnology, Chubu University, 1200 Matsumoto-cho, Kasugai, Aichi, 478-8501, Japan.; Department of Electrical and Electronic Engineering, Faculty of Science and Technology, Meijo University, 1-501 Shiogamaguchi, Tempaku-ku, Nagoya, Aichi, 468-8502, Japan.
Lateral roots (LRs) are critical to root system architecture development in plants. Although the molecular mechanisms by which auxin regulates LR development have been extensively studied, several additional regulatory systems are hypothesized to be involved. Recently, the regulatory role of very long chain fatty acids (VLCFAs) has been shown in LR development. Our analysis showed that LTPG1 and LTPG2, transporters of VLCFAs, are specifically expressed in the developing LR primordium (LRP), while the number of LRs is reduced in the ltpg1/ltpg2 double mutant. Moreover, late LRP development was hindered when the VLCFAs levels were reduced by the VLCFA synthesis enzyme mutant, kcs1-5. However, the details of the regulatory mechanisms of LR development controlled by VLCFAs remain unknown. In this study, we propose a novel method to analyze the LRP development stages with high temporal resolution using a deep neural network and identify a VLCFA-responsive transcription factor, MYB93, via transcriptome analysis of kcs1-5. MYB93 showed a carbon chain length-specific expression response following treatment of VLCFAs. Furthermore, myb93 transcriptome analysis suggested that MYB93 regulated the expression of cell wall organization genes. Additionally, we also found that LTPG1 and LTPG2 are involved in LR development through the formation of root cap cuticle (RCC), which is different from transcriptional regulation by VLCFAs. Our results suggest that VLCFA is a regulator of LRP development through transcription factor-mediated regulation of gene expression and the transportation of VLCFAs is also involved in LR development through RCC formation.
PMID: 37247130
Plant J , IF:6.417 , 2023 May doi: 10.1111/tpj.16328
ELONGATED HYPOCOTYL5 (HY5) and HY5 HOMOLOG (HYH) maintain shade avoidance suppression in UV-B.
School of Biological Sciences, Life Sciences Building, University of Bristol, Bristol, BS8 1TQ, UK.; School of Molecular Biosciences, College of Medical, Veterinary and Life Sciences, University of Glasgow, G12 8QQ, Glasgow, UK.
Reductions in red to far-red ratio (R:FR) provide plants with an unambiguous signal of vegetational shade and are monitored by phytochrome photoreceptors. Plants integrate this information with other environmental cues to determine the proximity and density of encroaching vegetation. Shade-sensitive species respond to reductions in R:FR by initiating a suite of developmental adaptations termed shade avoidance. These include the elongation of stems to facilitate light foraging. Hypocotyl elongation is driven by increased auxin biosynthesis promoted by PHYTOCHROME INTERACTING FACTORs 4, 5 and 7. UV-B perceived by the UV RESISTANCE LOCUS 8 (UVR8) photoreceptor rapidly inhibits shade avoidance, in part, by suppressing PIF4/5 transcript accumulation and destabilising PIF4/5 protein. Here, we show that longer-term inhibition of shade avoidance is sustained by ELONGATED HYPOCOTYL 5 (HY5) and HY5 HOMOLOG (HYH) which regulate transcriptional reprogramming of genes involved in hormone signalling and cell wall modification. HY5 and HYH are elevated in UV-B and suppress the expression of XYLOGLUCAN ENDOTRANSGLUCOSYLASE/HYDROLASE (XTH) genes involved in cell wall loosening. They additionally increase expression GA2-OXIDASE1 (GA2ox1) and GA2ox2, encoding gibberellin (GA) catabolism enzymes which act redundantly to stabilise the PIF-inhibiting DELLA proteins. UVR8 therefore regulates temporally distinct signalling pathways to first rapidly inhibit and subsequently maintain suppression of shade avoidance following UV-B exposure.
PMID: 37243898
Plant J , IF:6.417 , 2023 May doi: 10.1111/tpj.16324
PIN2/3/4 Auxin Carriers Mediate Root Growth Inhibition under Conditions of Boron Deprivation in Arabidopsis.
International Research Center for Environmental Membrane Biology & Department of Horticulture, Foshan University, Foshan, 528000, China.; National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan, 430000, 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 Botany, Plant Science and Biodiversity Center, Slovak Academy of Sciences, Bratislava, Slovakia.; School of Agriculture and Environment & Institute of Agriculture, University of Western Australia, Perth, 6009, Australia.; Tasmanian Institute for Agriculture, College of Science and Engineering, University of Tasmania, Hobart, Tas, 7001, Australia.; School of Biological Sciences, University of Western Australia, Perth, 6009, Australia.; Institute of Cellular and Molecular Botany, University of Bonn, D-53115, Bonn, Germany.; Institute of Soil Science Chinese Academy of Sciences, State Key Laboratory of Soil and Sustainable Agriculture, Nanjing, 210018, China.
The mechanistic basis by which boron (B) deprivation inhibits root growth via the mediation of the root apical auxin transport and distribution remains elusive. This study showed that B deprivation repressed root growth of wild-type Arabidopsis seedlings, which was related to a higher auxin accumulation (observed with DII-VENUS and DR5-GFP lines) in B-deprived roots. Boron deprivation elevated the auxin content in the root apex, coinciding with up-regulation of the expression levels of auxin biosynthesis-related genes (TAA1, YUC3, YUC9, and NIT1) in shoots, but not in root apices. Phenotyping experiments using auxin transport-related mutants revealed that the PIN2/3/4 carriers are involved in root growth inhibition caused by B deprivation. B deprivation not only up-regulated the transcriptional levels of PIN2/3/4 genes, but also restrained the endocytosis of PIN2/3/4 carriers (observed with PIN-Dendra2 lines), resulting in elevated protein levels of PIN2/3/4 in the plasma membrane. Overall, these results suggest that B deprivation not only enhances auxin biosynthesis in shoots by elevating the expression levels of auxin biosynthesis-related genes but also promotes the polar auxin transport from shoots to roots by up-regulating the expression levels of PIN2/3/4 genes, as well as restrains the endocytosis of PIN2/3/4 carriers, ultimately resulting in auxin accumulation in root apices and root growth inhibition.
PMID: 37235684
Plant J , IF:6.417 , 2023 Apr doi: 10.1111/tpj.16218
Salicylic acid inhibits rice endocytic protein trafficking mediated by OsPIN3t and clathrin to affect root growth.
College of Plant Protection, Yunnan Agricultural University, Kunming, 650201, China.; State Key Laboratory for Conservation and Utilization of Bio-Resources in Yunnan, Yunnan Agricultural University, Kunming, 650201, China.; Key Laboratory of Agro-Biodiversity and Pest Management of Education Ministry of China, Yunnan Agricultural University, Kunming, 650201, China.; CAS Key Laboratory of Tropical Plant Resources and Sustainable Use, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Menglun, Mengla, 666303, Yunnan, China.; National Engineering Laboratory for Tree Breeding, Beijing Forestry University, Beijing, 100083, China.; Shanxi Agricultural University/Shanxi Academy of Agricultural Sciences, The Industrial Crop Institute, Fenyang, 032200, China.; Key Lab of Agricultural Biotechnology of Yunnan Province, Biotechnology and Germplasm Resources Research Institute, Yunnan Academy of Agricultural Sciences, Kunming, 650205, Yunnan, China.; Ministry of Education Key Laboratory of Molecular and Cellular Biology, Hebei Collaboration Innovation Center for Cell Signaling and Environmental Adaptation, Hebei Key Laboratory of Molecular and Cellular Biology, College of Life Sciences, Hebei Normal University, Shijiazhuang, 050024, China.; Institute of Science and Technology Austria (IST Austria), Klosterneuburg, Austria.; Center of Economic Botany, Core Botanical Gardens, Chinese Academy of Sciences, Menglun, Mengla, 666303, Yunnan, China.; The Innovative Academy of Seed Design, Chinese Academy of Sciences, Menglun, Mengla, 666303, Yunnan, China.
Salicylic acid (SA) plays important roles in different aspects of plant development, including root growth, where auxin is also a major player by means of its asymmetric distribution. However, the mechanism underlying the effect of SA on the development of rice roots remains poorly understood. Here, we show that SA inhibits rice root growth by interfering with auxin transport associated with the OsPIN3t- and clathrin-mediated gene regulatory network (GRN). SA inhibits root growth as well as Brefeldin A-sensitive trafficking through a non-canonical SA signaling mechanism. Transcriptome analysis of rice seedlings treated with SA revealed that the OsPIN3t auxin transporter is at the center of a GRN involving the coat protein clathrin. The root growth and endocytic trafficking in both the pin3t and clathrin heavy chain mutants were SA insensitivity. SA inhibitory effect on the endocytosis of OsPIN3t was dependent on clathrin; however, the root growth and endocytic trafficking mediated by tyrphostin A23 (TyrA23) were independent of the pin3t mutant under SA treatment. These data reveal that SA affects rice root growth through the convergence of transcriptional and non-SA signaling mechanisms involving OsPIN3t-mediated auxin transport and clathrin-mediated trafficking as key components.
PMID: 37025008
Plant J , IF:6.417 , 2023 May , V114 (3) : P683-698 doi: 10.1111/tpj.16166
FaMYB123 interacts with FabHLH3 to regulate the late steps of anthocyanin and flavonol biosynthesis 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.; Department of Agricultural Chemistry, University of Cordoba, Edificio Marie Curie, Campus de Rabanales, E-14014, Cordoba, Spain.; Department of Plant Biology, Instituto de Hortofruticultura Subtropical y Mediterranea La Mayora, University of Malaga, Campus de Teatinos, E-29071, Malaga, 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 strawberry (Fragaria x ananassa) 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 ABA 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 the contents of total anthocyanin and flavonoid, especially 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 an R2R3 MYB transcription factor, regulating the expression of a gene that encodes a malonyltransferase, has been elucidated.
PMID: 36840368
Plant J , IF:6.417 , 2023 Apr , V114 (1) : P176-192 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 Apr , V114 (1) : P83-95 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
Ecotoxicol Environ Saf , IF:6.291 , 2023 Apr , V255 : P114777 doi: 10.1016/j.ecoenv.2023.114777
Galactoglucomannan oligosaccharides alleviate cadmium toxicity by improving physiological processes in maize.
Institute of Chemistry, Slovak Academy of Sciences, Dubravska cesta 9, 845 38 Bratislava, Slovakia.; Department of Botany, Institute of Biology and Ecology, Safarik University, Manesova 23, 040 01 Kosice, Slovakia.; Institute of Chemistry, Slovak Academy of Sciences, Dubravska cesta 9, 845 38 Bratislava, Slovakia. Electronic address: karin.kollarova@savba.sk.
Phosphate fertilisers and past mining activity are significant source of cadmium (Cd) pollution; thus, the concentration of Cd in agricultural soils has been substantially rising. Various substances have been tested for their potential to alleviate the toxicity of Cd and stimulate the accumulation of Cd in plant organs. This study brought new insight of the impact of galactoglucomannan oligosaccharides (GGMOs) on the maize plants grown under/in Cd stress. The application of GGMOs reduced concentration of Cd in the maize leaves and thus GGMOs increased their growth (by 24%), concentration of photosynthetic pigments (up to 39.4%), effective quantum yield of photosystem II (up to 29.6%), and net photosynthetic rate (up to 19.6%). The concentrations of stress markers increased in the Cd and Cd + GGMOs treatment; however, significantly lower concentration was detected in the Cd + GGMOs treatment (malondialdehyde by 21.7%, hydrogen peroxide by 13%). The concentration of auxin increased almost by two-fold in the Cd + GGMOs treatment compared to the Cd treatment. The recovered auxin level and enhanced nutrient uptake are proposed mechanisms of GGMOs' action during stress. GGMOs are molecules with biostimulant potential that could support vitality of maize plants in Cd stress.
PMID: 36931090
Commun Biol , IF:6.268 , 2023 Apr , V6 (1) : P457 doi: 10.1038/s42003-023-04835-w
Initiation of scutellum-derived callus is regulated by an embryo-like developmental pathway in rice.
Institute of Genetic and Regenerative Biology, Key Laboratory for Cell and Gene Engineering of Zhejiang Province, College of Life Sciences, Zhejiang University, Hangzhou, 310058, China.; Hainan Institute, Zhejiang University, Yazhou Bay Science and Technology City, Sanya, 572025, China.; Yazhou Bay Seed Laboratory, Yazhou Bay Science and Technology City, Yazhou District, Sanya, 572025, 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 the Chinese Academy of Sciences, 19A Yuquan Road, Beijing, 100049, China.; Institute of Cell Biology, School of Biological Sciences, The University of Edinburgh, Edinburgh, UK.; State Key Laboratory of Crop Biology, Shandong Key Laboratory of Crop Biology, College of Life Sciences, Shandong Agricultural University, Taian, Shandong, 271018, China.; Department of Chemistry, Seoul National University, Seoul, 08826, Korea.; Plant Genomics and Breeding Institute, Seoul National University, Seoul, 08826, Korea.; 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.; Institute of Genetic and Regenerative Biology, Key Laboratory for Cell and Gene Engineering of Zhejiang Province, College of Life Sciences, Zhejiang University, Hangzhou, 310058, China. hwbian@zju.edu.cn.
In rice (Oryza sativa) tissue culture, callus can be induced from the scutellum in embryo or from the vasculature of non-embryonic organs such as leaves, nodes, or roots. Here we show that the auxin signaling pathway triggers cell division in the epidermis of the scutellum to form an embryo-like structure, which leads to callus formation. Our transcriptome data show that embryo-, stem cell-, and auxin-related genes are upregulated during scutellum-derived callus initiation. Among those genes, the embryo-specific gene OsLEC1 is activated by auxin and involved in scutellum-derived callus initiation. However, OsLEC1 is not required for vasculature-derived callus initiation from roots. In addition, OsIAA11 and OsCRL1, which are involved in root development, are required for vasculature-derived callus formation but not for scutellum-derived callus formation. Overall, our data indicate that scutellum-derived callus initiation is regulated by an embryo-like development program, and this is different from vasculature-derived callus initiation which borrows a root development program.
PMID: 37100819
Commun Biol , IF:6.268 , 2023 Apr , V6 (1) : P372 doi: 10.1038/s42003-023-04731-3
LkARF7 and LkARF19 overexpression promote adventitious root formation in a heterologous poplar model by positively regulating LkBBM1.
State Key Laboratory of Tree Genetics and Breeding, Key Laboratory of Tree Breeding and Cultivation of State Forestry and Grassland Administration, Research Institute of Forestry, Chinese Academy of Forestry, Beijing, 100091, China.; Guangxi Forestry Research Institute, Guangxi, 530009, China.; College of Bioengineering and Biotechnology, Tianshui Normal University, Gansu, 741000, China.; State Key Laboratory of Tree Genetics and Breeding, Key Laboratory of Tree Breeding and Cultivation of State Forestry and Grassland Administration, Research Institute of Forestry, Chinese Academy of Forestry, Beijing, 100091, China. xmsun@caf.ac.cn.
Cuttage propagation involves adventitious root formation induced by auxin. In our previous study, Larix kaempferi BABY BOOM 1 (LkBBM1), which is known to regulate adventitious root formation, was affected by auxin. However, the relationship between LkBBM1 and auxin remains unclear. Auxin response factors (ARFs) are a class of important transcription factors in the auxin signaling pathway and modulate the expression of early auxin-responsive genes by binding to auxin response elements. In the present study, we identified 14 L. kaempferi ARFs (LkARFs), and found LkARF7 and LkARF19 bound to LkBBM1 promoter and enhanced its transcription using yeast one-hybrid, ChIP-qPCR, and dual-luciferase assays. In addition, the treatment with naphthalene acetic acid promoted the expression of LkARF7 and LkARF19. We also found that overexpression of these two genes in poplar promoted adventitious root formation. Furthermore, LkARF19 interacted with the DEAD-box ATP-dependent RNA helicase 53-like protein to form a heterodimer to regulate adventitious root formation. Altogether, our results reveal an additional regulatory mechanism underlying the control of adventitious root formation by auxin.
PMID: 37020138
J Ginseng Res , IF:6.06 , 2023 May , V47 (3) : P469-478 doi: 10.1016/j.jgr.2022.05.009
Nitrate enhances the secondary growth of storage roots in Panax ginseng.
Department of Biology, Chungbuk National University, Cheongju, Republic of Korea.; Department of Biological Sciences, Chungnam National University, Daejeon, Republic of Korea.; Ginseng & Medicinal Plant Research Institute, Chungnam Agricultural Research & Extention Service, Keumsan, Republic of Korea.; Department of Herbal Crop Research, National Institute of Horticultural and Herbal Science, Rural Development Administration, Eumseong, Republic of Korea.; Korea Ginseng Corporation, R&D Headquarters, Daejeon, Republic of Korea.; Theragen Bio Co., Ltd, Suwon, Republic of Korea.; Department of Biological Sciences and Biotechnology, Chungbuk National University, Cheongju, Republic of Korea.
BACKGROUND: Nitrogen (N) is an essential macronutrient for plant growth and development. To support agricultural production and enhance crop yield, two major N sources, nitrate and ammonium, are applied as fertilizers to the soil. Although many studies have been conducted on N uptake and signal transduction, the molecular genetic mechanisms of N-mediated physiological roles, such as the secondary growth of storage roots, remain largely unknown. METHODS: One-year-old P. ginseng seedlings treated with KNO(3) were analyzed for the secondary growth of storage roots. The histological paraffin sections were subjected to bright and polarized light microscopic analysis. Genome-wide RNA-seq and network analysis were carried out to dissect the molecular mechanism of nitrate-mediated promotion of ginseng storage root thickening. RESULTS: Here, we report the positive effects of nitrate on storage root secondary growth in Panax ginseng. Exogenous nitrate supply to ginseng seedlings significantly increased the root secondary growth. Histological analysis indicated that the enhancement of root secondary growth could be attributed to the increase in cambium stem cell activity and the subsequent differentiation of cambium-derived storage parenchymal cells. RNA-seq and gene set enrichment analysis (GSEA) revealed that the formation of a transcriptional network comprising auxin, brassinosteroid (BR)-, ethylene-, and jasmonic acid (JA)-related genes mainly contributed to the secondary growth of ginseng storage roots. In addition, increased proliferation of cambium stem cells by a N-rich source inhibited the accumulation of starch granules in storage parenchymal cells. CONCLUSION: Thus, through the integration of bioinformatic and histological tissue analyses, we demonstrate that nitrate assimilation and signaling pathways are integrated into key biological processes that promote the secondary growth of P. ginseng storage roots.
PMID: 37252286
Int J Mol Sci , IF:5.923 , 2023 May , V24 (10) doi: 10.3390/ijms24108748
Comparative Anatomical and Transcriptomics Reveal the Larger Cell Size as a Major Contributor to Larger Fruit Size in Apricot.
State Key Laboratory of Tree Genetics and Breeding, Research Institute of Non-Timber Forestry, Chinese Academy of Forestry, Zhengzhou 450003, China.; College of Forestry, Nanjing Forestry University, Nanjing 210037, China.; Kernel-Apricot Engineering and Technology Research Center of State Forestry and Grassland Administration, Zhengzhou 450003, China.; Key Laboratory of Non-Timber Forest Germplasm Enhancement and Utilization of National Forestry and Grassland Administration, Zhengzhou 450003, China.
Fruit size is one of the essential quality traits and influences the economic value of apricots. To explore the underlying mechanisms of the formation of differences in fruit size in apricots, we performed a comparative analysis of anatomical and transcriptomics dynamics during fruit growth and development in two apricot cultivars with contrasting fruit sizes (large-fruit Prunus armeniaca 'Sungold' and small-fruit P. sibirica 'F43'). Our analysis identified that the difference in fruit size was mainly caused by the difference in cell size between the two apricot cultivars. Compared with 'F43', the transcriptional programs exhibited significant differences in 'Sungold', mainly in the cell expansion period. After analysis, key differentially expressed genes (DEGs) most likely to influence cell size were screened out, including genes involved in auxin signal transduction and cell wall loosening mechanisms. Furthermore, weighted gene co-expression network analysis (WGCNA) revealed that PRE6/bHLH was identified as a hub gene, which interacted with 1 TIR1, 3 AUX/IAAs, 4 SAURs, 3 EXPs, and 1 CEL. Hence, a total of 13 key candidate genes were identified as positive regulators of fruit size in apricots. The results provide new insights into the molecular basis of fruit size control and lay a foundation for future breeding and cultivation of larger fruits in apricot.
PMID: 37240096
Int J Mol Sci , IF:5.923 , 2023 May , V24 (10) doi: 10.3390/ijms24108735
ZmDRR206 Regulates Nutrient Accumulation in Endosperm through Its Role in Cell Wall Biogenesis during Maize Kernel Development.
National Maize Improvement Center, Center for Crop Functional Genomics and Molecular Breeding, Department of Plant Genetics and Breeding, China Agricultural University, Beijing 100193, China.
Dirigent proteins (DIRs) contribute to plant fitness by dynamically reorganizing the cell wall and/or by generating defense compounds during plant growth, development, and interactions with environmental stresses. ZmDRR206 is a maize DIR, it plays a role in maintaining cell wall integrity during seedling growth and defense response in maize, but its role in regulating maize kernel development is unclear. Association analysis of candidate genes indicated that the natural variations of ZmDRR206 were significantly associated with maize hundred-kernel weight (HKW). ZmDRR206 plays a dominant role in storage nutrient accumulation in endosperm during maize kernel development, ZmDRR206 overexpression resulted in small and shrunken maize kernel with significantly reduced starch content and significantly decreased HKW. Cytological characterization of the developing maize kernels revealed that ZmDRR206 overexpression induced dysfunctional basal endosperm transfer layer (BETL) cells, which were shorter with less wall ingrowth, and defense response was constitutively activated in developing maize kernel at 15 and 18 DAP by ZmDRR206 overexpression. The BETL-development-related genes and auxin signal-related genes were down-regulated, while cell wall biogenesis-related genes were up-regulated in developing BETL of the ZmDRR206-overexpressing kernel. Moreover, the developing ZmDRR206-overexpressing kernel had significantly reduced contents of the cell wall components such as cellulose and acid soluble lignin. These results suggest that ZmDRR206 may play a regulatory role in coordinating cell development, storage nutrient metabolism, and stress responses during maize kernel development through its role in cell wall biogenesis and defense response, and provides new insights into understanding the mechanisms of kernel development in maize.
PMID: 37240079
Int J Mol Sci , IF:5.923 , 2023 May , V24 (10) doi: 10.3390/ijms24108692
Griseofulvin Inhibits Root Growth by Targeting Microtubule-Associated Proteins Rather Tubulins in Arabidopsis.
Weed Research Laboratory, Nanjing Agricultural University, Nanjing 210095, China.; Institute of Technology and Life Sciences; National Research Institute, Falenty, Al. Hrabska 3, 05-090 Raszyn, Poland.; Department of Plant Physiology, Institute of Biology, Warsaw University of Life Sciences SGGW, 159 Nowoursynowska 159, 02-776 Warsaw, Poland.
Griseofulvin was considered an effective agent for cancer therapy in past decades. Although the negative effects of griseofulvin on microtubule stability are known, the exact target and mechanism of action in plants remain unclear. Here, we used trifluralin, a well-known herbicide targeting microtubules, as a reference and revealed the differences in root tip morphology, reactive oxygen species production (ROS), microtubule dynamics, and transcriptome analysis between Arabidopsis treated with griseofulvin and trifluralin to elucidate the mechanism of root growth inhibition by griseofulvin. Like trifluralin, griseofulvin inhibited root growth and caused significant swelling of the root tip due to cell death induced by ROS. However, the presence of griseofulvin and trifluralin caused cell swelling in the transition zone (TZ) and meristematic zone (MZ) of root tips, respectively. Further observations revealed that griseofulvin first destroyed cortical microtubules in the cells of the TZ and early elongation zone (EZ) and then gradually affected the cells of other zones. The first target of trifluralin is the microtubules in the root MZ cells. Transcriptome analysis showed that griseofulvin mainly affected the expression of microtubule-associated protein (MAP) genes rather than tubulin genes, whereas trifluralin significantly suppressed the expression of alphabeta-tubulin genes. Finally, it was proposed that griseofulvin could first reduce the expression of MAP genes, meanwhile increasing the expression of auxin and ethylene-related genes to disrupt microtubule alignment in root tip TZ and early EZ cells, induce dramatic ROS production, and cause severe cell death, eventually leading to cell swelling in the corresponding zones and inhibition of root growth.
PMID: 37240033
Int J Mol Sci , IF:5.923 , 2023 May , V24 (10) doi: 10.3390/ijms24108514
Precise Regulation of the TAA1/TAR-YUCCA Auxin Biosynthesis Pathway in Plants.
College of Life Science and Technology, Gansu Agricultural University, Lanzhou 730070, China.; State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, China.
The indole-3-pyruvic acid (IPA) pathway is the main auxin biosynthesis pathway in the plant kingdom. Local control of auxin biosynthesis through this pathway regulates plant growth and development and the responses to biotic and abiotic stresses. During the past decades, genetic, physiological, biochemical, and molecular studies have greatly advanced our understanding of tryptophan-dependent auxin biosynthesis. The IPA pathway includes two steps: Trp is converted to IPA by TRYPTOPHAN AMINOTRANSFERASE OF ARABIDOPSIS/TRYPTOPHAN AMINOTRANSFERASE RELATED PROTEINs (TAA1/TARs), and then IPA is converted to IAA by the flavin monooxygenases (YUCCAs). The IPA pathway is regulated at multiple levels, including transcriptional and post-transcriptional regulation, protein modification, and feedback regulation, resulting in changes in gene transcription, enzyme activity and protein localization. Ongoing research indicates that tissue-specific DNA methylation and miRNA-directed regulation of transcription factors may also play key roles in the precise regulation of IPA-dependent auxin biosynthesis in plants. This review will mainly summarize the regulatory mechanisms of the IPA pathway and address the many unresolved questions regarding this auxin biosynthesis pathway in plants.
PMID: 37239863
Int J Mol Sci , IF:5.923 , 2023 May , V24 (9) doi: 10.3390/ijms24098440
Lateral Root Initiation in Cucumber (Cucumis sativus): What Does the Expression Pattern of Rapid Alkalinization Factor 34 (RALF34) Tell Us?
Laboratory of Cellular and Molecular Mechanisms of Plant Development, Komarov Botanical Institute, Russian Academy of Sciences, 197022 Saint Petersburg, Russia.; Department of Ecology, Environment and Plant Sciences, Stockholm University, 10691 Stockholm, Sweden.
In Arabidopsis, the small signaling peptide (peptide hormone) RALF34 is involved in the gene regulatory network of lateral root initiation. In this study, we aimed to understand the nature of the signals induced by RALF34 in the non-model plant cucumber (Cucumis sativus), where lateral root primordia are induced in the apical meristem of the parental root. The RALF family members of cucumber were identified using phylogenetic analysis. The sequence of events involved in the initiation and development of lateral root primordia in cucumber was examined in detail. To elucidate the role of the small signaling peptide CsRALF34 and its receptor CsTHESEUS1 in the initial stages of lateral root formation in the parental root meristem in cucumber, we studied the expression patterns of both genes, as well as the localization and transport of the CsRALF34 peptide. CsRALF34 is expressed in all plant organs. CsRALF34 seems to differ from AtRALF34 in that its expression is not regulated by auxin. The expression of AtRALF34, as well as CsRALF34, is regulated in part by ethylene. CsTHESEUS1 is expressed constitutively in cucumber root tissues. Our data suggest that CsRALF34 acts in a non-cell-autonomous manner and is not involved in lateral root initiation in cucumber.
PMID: 37176146
Int J Mol Sci , IF:5.923 , 2023 Apr , V24 (9) doi: 10.3390/ijms24097691
Study on the Flower Induction Mechanism of Hydrangea macrophylla.
Beijing Key Laboratory of Ornamental Plants Germplasm Innovation & Molecular Breeding, China National Engineering Research Center for Floriculture, College of Landscape Architecture, Beijing Forestry University, Beijing 100083, China.; Beijing Flower Engineering Technology Research Center, Plant Institute, China National Botanical Garden North Park, Beijing 100093, China.
The flower induction of Hydrangea macrophylla "Endless Summer" is regulated by a complex gene network that involves multiple signaling pathways to ensure continuous flowering throughout the growing season, but the molecular determinants of flower induction are not yet clear. In this study, genes potentially involved in signaling pathway mediating the regulatory mechanism of flower induction were identified through the transcriptomic profiles, and a hypothetical model for this regulatory mechanism was obtained by an analysis of the available transcriptomic data, suggesting that sugar-, hormone-, and flowering-related genes participated in the flower induction process of H. macrophylla "Endless Summer". The expression profiles of the genes involved in the biosynthesis and metabolism of sugar showed that the beta-amylase gene BAM1 displayed a high expression level at the BS2 stage and implied the hydrolysis of starch. It may be a signaling molecule that promotes the transition from vegetative growth to reproductive growth in H. macrophylla "Endless Summer". Complex hormone regulatory networks involved in abscisic acid (ABA), auxin (IAA), zeatin nucleoside (ZR), and gibberellin (GA) also induced flower formation in H. macrophylla. ABA participated in flower induction by regulating flowering genes. The high content of IAA and the high expression level of the auxin influx carrier gene LAX5 at the BS2 stage suggested that the flow of auxin between sources and sinks in H. macrophylla is involved in the regulation of floral induction as a signal. In addition, flowering-related genes were mainly involved in the photoperiodic pathway, the aging pathway, and the gibberellin pathway. As a result, multiple pathways, including the photoperiodic pathway, the aging pathway, and the gibberellin pathway, which were mainly mediated by crosstalk between sugar and hormone signals, regulated the molecular network involved in flower induction in H. macrophylla "Endless Summer".
PMID: 37175398
Int J Mol Sci , IF:5.923 , 2023 Apr , V24 (8) doi: 10.3390/ijms24087590
Comparative Physiological and Transcriptomic Mechanisms of Defoliation in Cotton in Response to Thidiazuron versus Ethephon.
Engineering Research Center of Plant Growth Regulator, Ministry of Education & College of Agronomy and Biotechnology, China Agricultural University, Beijing 100193, China.; State Key Laboratory of Plant Physiology and Biochemistry, China Agricultural University, Beijing 100193, China.
Thidiazuron (TDZ) is a widely used chemical defoliant in cotton and can stimulate the production of ethylene in leaves, which is believed to be the key factor in inducing leaf abscission. Ethephon (Eth) can also stimulate ethylene production in leaves, but it is less effective in promoting leaf shedding. In this study, the enzyme-linked immunosorbent assays (ELISA) and RNA-seq were used to determine specific changes at hormonal levels as well as transcriptomic mechanisms induced by TDZ compared with Eth. The TDZ significantly reduced the levels of auxin and cytokinin in cotton leaves, but no considerable changes were observed for Eth. In addition, TDZ specifically increased the levels of brassinosteroids and jasmonic acid in the leaves. A total of 13 764 differentially expressed genes that specifically responded to TDZ were identified by RNA-seq. The analysis of KEGG functional categories suggested that the synthesis, metabolism, and signal transduction of auxin, cytokinin, and brassinosteroid were all involved in the TDZ-induced abscission of cotton leaves. Eight auxin transport genes (GhPIN1-c_D, GhPIN3_D, GhPIN8_A, GhABCB19-b_A, GhABCB19-b_D, GhABCB2-b_D, GhLAX6_A, and GhLAX7_D) specifically responded to TDZ. The pro35S::GhPIN3a::YFP transgenic plants showed lower defoliation than the wild type treated with TDZ, and YFP fluorescence in leaves was almost extinguished after treatment with TDZ rather than Eth. This provides direct evidence that GhPIN3a is involved in the leaf abscission induced by TDZ. We found that 959 transcription factors (TFs) specifically responded to TDZ, and a co-expression network analysis (WGCNA) showed five hub TFs (GhNAC72, GhWRKY51, GhWRKY70, GhWRKY50, and GhHSF24) during chemical defoliation with TDZ. Our work sheds light on the molecular basis of TDZ-induced leaf abscission in cotton.
PMID: 37108752
Int J Mol Sci , IF:5.923 , 2023 Apr , V24 (8) doi: 10.3390/ijms24087566
Genome-Wide Identification and Expression Analysis of NCED Gene Family in Pear and Its Response to Exogenous Gibberellin and Paclobutrazol.
Department of Horticulture, College of Agriculture, Shihezi University, Shihezi 832003, China.; Xinjiang Production and Construction Corps Key Laboratory of Special Fruits and Vegetables Cultivation Physiology and Germplasm Resources Utilization, Shihezi 832003, China.
The 9-cis-epoxycarotenoid dioxygenase (NCED) is a key enzyme for the process of ABA synthesis that plays key roles in a variety of biological processes. In the current investigation, genome-wide identification and comprehensive analysis of the NCED gene family in 'Kuerle Xiangli' (Pyrus sinkiangensis Yu) were conducted using the pear genomic sequence. In total, nineteen members of PbNCED genes were identified from the whole genome of pear, which are not evenly distributed over the scaffolds, and most of which were focussed in the chloroplasts. Sequence analysis of promoters showed many cis-regulatory elements, which presumably responded to phytohormones such as abscisic acid, auxin, etc. Synteny block indicated that the PbNCED genes have experienced strong purifying selection. Multiple sequence alignment demonstrated that these members are highly similar and conserved. In addition, we found that PbNCED genes were differentially expressed in various tissues, and three PbNCED genes (PbNCED1, PbNCED2, and PbNCED13) were differentially expressed in response to exogenous Gibberellin (GA(3)) and Paclobutrazol (PP(333)). PbNCED1 and PbNCED13 positively promote ABA synthesis in sepals after GA(3) and PP(333) treatment, whereas PbNCED2 positively regulated ABA synthesis in ovaries after GA(3) treatment, and PbNCED13 positively regulated ABA synthesis in the ovaries after PP(333) treatment. This study was the first genome-wide report of the pear NCED gene family, which could improve our understanding of pear NCED proteins and provide a solid foundation for future cloning and functional analyses of this gene family. Meanwhile, our results also give a better understanding of the important genes and regulation pathways related to calyx abscission in 'Kuerle Xiangli'.
PMID: 37108747
Int J Mol Sci , IF:5.923 , 2023 Apr , V24 (8) doi: 10.3390/ijms24087290
Integration of mRNA and miRNA Analysis Reveals the Post-Transcriptional Regulation of Salt Stress Response in Hemerocallis fulva.
Key Laboratory of Saline-Alkali Vegetation Ecology Restoration, Northeast Forestry University, Ministry of Education, Harbin 150040, China.; College of Life Science, Northeast Forestry University, Harbin 150040, China.; Key Laboratory of Molecular Epigenetics of MOE, Institute of Genetics & Cytology, Northeast Normal University, Changchun 130024, China.; Horticulture Science and Engineering, Shandong Agricultural University, Taian 271018, China.
MicroRNAs (miRNAs) belong to non-coding small RNAs which have been shown to take a regulatory function at the posttranscriptional level in plant growth development and response to abiotic stress. Hemerocallis fulva is an herbaceous perennial plant with fleshy roots, wide distribution, and strong adaptability. However, salt stress is one of the most serious abiotic stresses to limit the growth and production of Hemerocallis fulva. To identify the miRNAs and their targets involved in the salt stress resistance, the salt-tolerant H. fulva with and without NaCl treatment were used as materials, and the expression differences of miRNAs-mRNAs related to salt-tolerance were explored and the cleavage sites between miRNAs and targets were also identified by using degradome sequencing technology. In this study, twenty and three significantly differential expression miRNAs (p-value < 0.05) were identified in the roots and leaves of H. fulva separately. Additionally, 12,691 and 1538 differentially expressed genes (DEGs) were also obtained, respectively, in roots and leaves. Moreover, 222 target genes of 61 family miRNAs were validated by degradome sequencing. Among the DE miRNAs, 29 pairs of miRNA targets displayed negatively correlated expression profiles. The qRT-PCR results also showed that the trends of miRNA and DEG expression were consistent with those of RNA-seq. A gene ontology (GO) enrichment analysis of these targets revealed that the calcium ion pathway, oxidative defense response, microtubule cytoskeleton organization, and DNA binding transcription factor responded to NaCl stress. Five miRNAs, miR156, miR160, miR393, miR166, and miR396, and several hub genes, squamosa promoter-binding-like protein (SPL), auxin response factor 12 (ARF), transport inhibitor response 1-like protein (TIR1), calmodulin-like proteins (CML), and growth-regulating factor 4 (GRF4), might play central roles in the regulation of NaCl-responsive genes. These results indicate that non-coding small RNAs and their target genes that are related to phytohormone signaling, Ca(2+) signaling, and oxidative defense signaling pathways are involved in H. fulva's response to NaCl stress.
PMID: 37108448
Int J Mol Sci , IF:5.923 , 2023 Apr , V24 (8) doi: 10.3390/ijms24087172
Prenyl Transferases Regulate Secretory Protein Sorting and Parasite Morphology in Toxoplasma gondii.
National Key Laboratory of Veterinary Public Health Security, School of Veterinary Medicine, China Agricultural University, Beijing 100193, China.; Center for Gene Regulation in Health and Disease, Department of Biological, Geological and Environmental Sciences, College of Sciences and Health Professions, Cleveland State University, Cleveland, OH 44115, USA.
Protein prenylation is an important protein modification that is responsible for diverse physiological activities in eukaryotic cells. This modification is generally catalyzed by three types of prenyl transferases, which include farnesyl transferase (FT), geranylgeranyl transferase (GGT-1) and Rab geranylgeranyl transferase (GGT-2). Studies in malaria parasites showed that these parasites contain prenylated proteins, which are proposed to play multiple functions in parasites. However, the prenyl transferases have not been functionally characterized in parasites of subphylum Apicomplexa. Here, we functionally dissected functions of three of the prenyl transferases in the Apicomplexa model organism Toxoplasma gondii (T. gondii) using a plant auxin-inducible degron system. The homologous genes of the beta subunit of FT, GGT-1 and GGT-2 were endogenously tagged with AID at the C-terminus in the TIR1 parental line using a CRISPR-Cas9 approach. Upon depletion of these prenyl transferases, GGT-1 and GGT-2 had a strong defect on parasite replication. Fluorescent assay using diverse protein markers showed that the protein markers ROP5 and GRA7 were diffused in the parasites depleted with GGT-1 and GGT-2, while the mitochondrion was strongly affected in parasites depleted with GGT-1. Importantly, depletion of GGT-2 caused the stronger defect to the sorting of rhoptry protein and the parasite morphology. Furthermore, parasite motility was observed to be affected in parasites depleted with GGT-2. Taken together, this study functionally characterized the prenyl transferases, which contributed to an overall understanding of protein prenylation in T. gondii and potentially in other related parasites.
PMID: 37108334
Int J Mol Sci , IF:5.923 , 2023 Apr , V24 (8) doi: 10.3390/ijms24087081
KNOX Genes Were Involved in Regulating Axillary Bud Formation of Chrysanthemum x morifolium.
Beijing Key Laboratory of Ornamental Plants Germplasm Innovation & Molecular Breeding, Beijing 100083, China.; National Engineering Research Center for Floriculture, Beijing 100083, China.; Beijing Laboratory of Urban and Rural Ecological Environment, Beijing 100083, China.; Engineering Research Center of Landscape Environment of Ministry of Education, Beijing 100083, China.; Key Laboratory of Genetics and Breeding in Forest Trees and Ornamental Plants of Ministry of Education, Beijing 100083, China.; School of Landscape Architecture, Beijing Forestry University, Beijing 100083, China.
Branching is an important agronomic and economic trait in cut chrysanthemums. The axillary meristem (AM) formation of the axillary buds of cut chrysanthemums has a decisive role in its branching characteristics. However, little is known about the regulation mechanism of axillary meristem formation in chrysanthemums at the molecular level. Members of the Homeobox gene family especially genes belonging to the class I KNOX branch play a key role in regulating the axillary bud growth and development processes of plants. In this study, three genes belonging to the class I KNOX branch, CmKNAT1, CmKNAT6, and CmSTM were cloned from chrysanthemums, and their functions in regulating axillary bud formation were examined. The subcellular localization test showed that these three KNOX genes were expressed in the nucleus, so all of them might function as transcription factors. The results of the expression profile analysis showed that these three KNOX genes were highly expressed in the AM formation stage of axillary buds. Overexpression of KNOX genes result in a wrinkled leaf phenotype in tobacco and Arabidopsis, which may be related to the excessive division of leaf cells, resulting in the proliferation of leaf tissue. Furthermore, overexpression of these three KNOX genes enhances the regeneration ability of tobacco leaves, indicating that these three KNOX genes may participate in the regulation of cell meristematic ability, thus promoting the formation of buds. In addition, the results of fluorescence quantitative testing showed that these three KNOX genes may promote the formation of chrysanthemum axillary buds by promoting the cytokinin pathway while inhibiting the auxin and gibberellin pathways. In conclusion, this study demonstrated that CmKNAT1, CmKNAT6, and CmSTM genes were involved in regulating axillary bud formation of Chrysanthemum x morifolium and preliminarily revealed the molecular mechanism of their regulation of AM formation. These findings may provide a theoretical basis and candidate gene resources for genetic engineering breeding of new varieties of cut chrysanthemums without lateral branches.
PMID: 37108245
Int J Mol Sci , IF:5.923 , 2023 Apr , V24 (7) doi: 10.3390/ijms24076647
Salinity-Triggered Responses in Plant Apical Meristems for Developmental Plasticity.
Department of Biotechnology, Duksung Women's University, Seoul 03169, Republic of Korea.
Salt stress severely affects plant growth and development. The plant growth and development of a sessile organism are continuously regulated and reformed in response to surrounding environmental stress stimuli, including salinity. In plants, postembryonic development is derived mainly from primary apical meristems of shoots and roots. Therefore, to understand plant tolerance and adaptation under salt stress conditions, it is essential to determine the stress response mechanisms related to growth and development based on the primary apical meristems. This paper reports that the biological roles of microRNAs, redox status, reactive oxygen species (ROS), nitric oxide (NO), and phytohormones, such as auxin and cytokinin, are important for salt tolerance, and are associated with growth and development in apical meristems. Moreover, the mutual relationship between the salt stress response and signaling associated with stem cell homeostasis in meristems is also considered.
PMID: 37047619
Int J Mol Sci , IF:5.923 , 2023 Mar , V24 (7) doi: 10.3390/ijms24076570
Transcriptomic Analysis of Hormone Signal Transduction, Carbohydrate Metabolism, Heat Shock Proteins, and SCF Complexes before and after Fertilization of Korean Pine Ovules.
State Key Laboratory of Tree Genetics and Breeding, School of Forestry, Northeast Forestry University, Harbin 150040, China.; Jilin Provincial Academy of Forestry Sciences, Changchun 130033, China.; State Forestry and Grassland Administration Engineering Technology Research Center of Korean Pine, Harbin 150040, China.
The fertilization process is a critical step in plant reproduction. However, the mechanism of action and mode of regulation of the fertilization process in gymnosperms remain unclear. In this study, we investigated the molecular regulatory networks involved in the fertilization process in Korean pine ovules through anatomical observation, physiological and biochemical assays, and transcriptome sequencing technology. The morphological and physiological results indicated that fertilization proceeds through the demise of the proteinaceous vacuole, egg cell division, and pollen tube elongation. Auxin, cytokinin, soluble sugar, and soluble starch contents begin to decline upon fertilization. Transcriptomic data analysis revealed a large number of differentially expressed genes at different times before and after fertilization. These genes were primarily involved in pathways associated with plant hormone signal transduction, protein processing in the endoplasmic reticulum, fructose metabolism, and mannose metabolism. The expression levels of several key genes were further confirmed by qRT-PCR. These findings represent an important step towards understanding the mechanisms underlying morphological changes in the Korean pine ovule during fertilization, and the physiological and transcriptional analyses lay a foundation for in-depth studies of the molecular regulatory network of the Korean pine fertilization process.
PMID: 37047551
Front Plant Sci , IF:5.753 , 2023 , V14 : P1142868 doi: 10.3389/fpls.2023.1142868
Transcriptome profiling of high and low somatic embryogenesis rate of oil palm (Elaeis guineensis Jacq. var. Tenera).
Biotechnology Department, Plant Production and Biotechnology Division, PT SMART Tbk, Bogor, Indonesia.; Agronomy and Horticulture Department, Agriculture Faculty, Bogor Agricultural University, Bogor, Indonesia.
Oil palm micropropagation through tissue culture is a technique to provide elite oil palms to meet the desired traits. This technique is commonly carried out through somatic embryogenesis. However, the oil palm's somatic embryogenesis rate is quite low. Several approaches have been made to overcome this problem, including transcriptome profiling through RNA-seq to identify key genes involved in oil palm somatic embryogenesis. RNA sequencing was applied in high- and low-embryogenic ortets of Tenera varieties based on the somatic embryoid rate at the callus, globular, scutellar, and coleoptilar embryoid stages. Cellular analysis of embryoid inductions and proliferations showed that high-embryogenic ortets resulted in higher embryoid proliferation and germinations than low-embryogenic ortets. Transcriptome profiling showed that there are a total of 1,911 differentially expressed genes (DEGs) between high- and low-embryogenic ortets. ABA signaling-related genes such as LEA, DDX28, and vicilin-like protein are upregulated in high-embryogenic ortets. Furthermore, DEGs associated with other hormone signaling, such as HD-ZIP associated with brassinosteroids and NPF associated with auxin, are upregulated in high-embryogenic ortets. This result suggests a physiological difference between high- and low-embryogenic ortets that is connected to their capacity for somatic embryogenesis. These DEGs will be used as potential biomarkers for high-embryogenic ortets and will be validated in further studies.
PMID: 37251752
Front Plant Sci , IF:5.753 , 2023 , V14 : P1172059 doi: 10.3389/fpls.2023.1172059
Auxin inhibits chlorophyll accumulation through ARF7-IAA14-mediated repression of chlorophyll biosynthesis genes in Arabidopsis.
College of Physics and Optoelectronic Engineering, Shenzhen University, Shenzhen, China.; Guangdong Provincial Key Laboratory for Plant Epigenetics, Longhua Bioindustry and Innovation Research Institute, College of Life Sciences and Oceanography, Shenzhen University, Shenzhen, China.; College of Bioscience and Biotechnology, Hunan Agricultural University, Changsha, China.
Auxin is a well-known important phytohormone in plant that plays vital roles in almost every development process throughout plant lifecycle. However, the effect of auxin on the metabolism of chlorophyll, one of the most important pigments involved in the photosynthesis, was intertwined and the underlying mechanism remained to be explored. Here, we found the auxin-defective yuc2 yuc6 double mutant displayed dark-green leaf color with higher chlorophyll content than wildtype, suggesting a negative regulatory role of auxin in chlorophyll biosynthesis. The chloroplast number and structure in mesophyll cells were altered and the photosynthetic efficiency was improved in yuc2 yuc6. In addition, the chlorophyll level was significantly improved during seedling de-etiolation in yuc2 yuc6 mutant, and decreased dramatically under IAA treatment, confirming the inhibitory role of auxin in chlorophyll biosynthesis. The analyses of gene expression in mature leaves and de-etiolation seedlings suggested that auxin suppressed the expression of many chlorophyll biosynthesis genes, especially PROTOCHLOROPHYLLIDE OXIDOREDUCTASE A (PORA) and GENOMES UNCOUPLED 5 (GUN5). Yeast-one-hybrid and luciferase assays demonstrated that the AUXIN RESPONSE FACTOR 2 (ARF2) and ARF7 bind to the promoter of PORA and GUN5 to suppress their expression with the help of INDOLE-3-ACETIC ACID14 (IAA14). Collectively, our research explicitly unraveled the direct inhibitory role of auxin in chlorophyll biosynthesis, and provided new insight into the interplay between auxin signaling and chlorophyll metabolism.
PMID: 37152161
Front Plant Sci , IF:5.753 , 2023 , V14 : P1133009 doi: 10.3389/fpls.2023.1133009
Asymmetric auxin distribution establishes a contrasting pattern of aerenchyma formation in the nodal roots of Zea nicaraguensis during gravistimulation.
Graduate School of Bioagricultural Sciences, Nagoya University, Nagoya, Aichi, Japan.; Bioscience and Biotechnology Center, Nagoya University, Nagoya, Aichi, Japan.; Division of Feed and Livestock Research, National Agriculture and Food Research Organization (NARO) Institute of Livestock and Grassland Science, Nasushiobara, Tochigi, Japan.; The University of Western Australia (UWA) School of Agriculture and Environment, The University of Western Australia, Crawley, WA, Australia.
Auxin distribution is essential for determining root developmental patterns. The formation of lateral roots and constitutive aerenchyma, which is a gas space developed through cell death, is regulated by auxin in rice (Oryza sativa). However, it is unclear whether the involvement of auxin in constitutive aerenchyma formation is conserved in other species. In this study, we found that constitutive aerenchyma formation was regulated by auxin in the nodal roots of Zea nicaraguensis, a wild relative of maize (Zea mays ssp. mays) grown naturally on frequently flooded coastal plains. Subsequent gravistimulation (root rotation) experiments showed opposite patterns of aerenchyma and lateral root formation. Lateral root formation on the convex side of rotated roots is known to be stimulated by a transient increase in auxin level in the pericycle. We found that aerenchyma formation was accelerated in the cortex on the concave side of the rotated nodal roots of Z. nicaraguensis. A cortex-specific expression analysis of auxin-responsive genes suggested that the auxin level was higher on the concave side than on the convex side. These results suggest that asymmetric auxin distribution underlies the regulation of aerenchyma and lateral root formation in the nodal roots of Z. nicaraguensis. As aerenchyma reduces the respiratory cost of the roots, constitutive aerenchyma on the concave side of the nodal root may balance resource allocation, thereby contributing to the uptake of water and nutrients by newly formed lateral roots. Our study provides insights into auxin-dependent asymmetric root patterning such as that of gravistimulation and hydropatterning response.
PMID: 37152158
Front Plant Sci , IF:5.753 , 2023 , V14 : P1158288 doi: 10.3389/fpls.2023.1158288
Identification of GA20ox2 as a target of ATHB2 and TCP13 during shade response.
Department of Biological Science and Institute of Women's Health, Sookmyung Women's University, Seoul, Republic of Korea.; Department of Systems Biology, Yonsei University, Seoul, Republic of Korea.
The shade avoidance syndrome (SAS) is a collective adaptive response of plants under shade highlighted by characteristic phenotypes such as hypocotyl elongation, which is largely mediated by concerted actions of auxin and GA. We identified ATHB2, a homeodomain-leucine zipper (HD-Zip) domain transcription factor known to be rapidly induced under shade condition, as a positive regulator of GA biosynthesis necessary for the SAS by transactivating the expression of GA20ox2, a key gene in the GA biosynthesis pathway. Based on promoter deletion analysis, EMSA and ChIP assay, ATHB2 appears to regulate the GA20ox2 expression as a direct binding target. We also found that the GA20ox2 expression is under negative control by TCP13, the effect of which can be suppressed by presence of ATHB2. Considering a rapid induction kinetics of ATHB2, this relationship between ATHB2 and TCP13 may allow ATHB2 to play a shade-specific activator for GA20ox by derepressing a pre-existing activity of TCP13.
PMID: 37152153
Front Plant Sci , IF:5.753 , 2023 , V14 : P1157309 doi: 10.3389/fpls.2023.1157309
Trans-cinnamaldehyde-related overproduction of benzoic acid and oxidative stress on Arabidopsis thaliana.
Departamento de Bioloxia Vexetal e Ciencia do Solo, Facultade de Bioloxia. Universidade de Vigo, Vigo, Spain.; Instituto de Ciencias de la Vid y del Vino, Consejo Superior de Investigaciones Cientificas, Universidad de La Rioja, La Rioja, Spain.; Departamento de Biologia Funcional, Universidade de Santiago de Compostela, Santiago de Compostela, Spain.; Dipartamento di Science Agrarie e Ambientali - Produzione, Territorio, Agroenergia, Universita Statale di Milano, Milano, Spain.; Departamento de Quimica Fisica, Facultade de Quimica, Universidade de Vigo, Vigo, Spain.; Departamento de Quimica Organica, Facultade de Quimica, Universidade de Vigo, Vigo, Spain.; Instituto de Investigacion Sanitaria Galicia Sur, Hospital Alvaro Cunqueiro, Vigo, Spain.
INTRODUCTION: Trans-cinnamaldehyde is a specialised metabolite that naturally occurs in plants of the Lauraceae family. This study focused on the phytotoxic effects of this compound on the morphology and metabolism of Arabidopsis thaliana seedlings. MATERIAL AND METHODS: To evaluate the phytotoxicity of trans-cinnamaldehyde, a dose-response curve was first performed for the root growth process in order to calculate the reference inhibitory concentrations IC50 and IC80 (trans-cinnamaldehyde concentrations inducing a 50% and 80% inhibition, respectively). Subsequently, the structure and ultrastructure of the roots treated with the compound were analysed by light and electron microscopy. Based on these results, the following assays were carried out to in depth study the possible mode of action of the compound: antiauxinic PCIB reversion bioassay, determination of mitochondrial membrane potential, ROS detection, lipid peroxidation content, hormone quantification, in silico studies and gene expression of ALDH enzymes. RESULTS: Trans-cinnamaldehyde IC50 and IC80 values were as low as 46 and 87 muM, reducing the root growth and inducing the occurrence of adventitious roots. At the ultrastructural level, the compound caused alterations to the mitochondria, which were confirmed by detection of the mitochondrial membrane potential. The morphology observed after the treatment (i.e., appearance of adventitious roots) suggested a possible hormonal mismatch at the auxin level, which was confirmed after PCIB bioassay and hormone quantification by GC-MS. The addition of the compound caused an increase in benzoic, salicylic and indoleacetic acid content, which was related to the increased gene expression of the aldehyde dehydrogenase enzymes that can drive the conversion of trans-cinnamaldehyde to cinnamic acid. Also, an increase of ROS was also observed in treated roots. The enzyme-compound interaction was shown to be stable over time by docking and molecular dynamics assays. DISCUSSION: The aldehyde dehydrogenases could drive the conversion of trans-cinnamaldehyde to cinnamic acid, increasing the levels of benzoic, salicylic and indoleacetic acids and causing the oxidative stress symptoms observed in the treated seedlings. This would result into growth and development inhibition of the trans-cinnamaldehyde-treated seedlings and ultimately in their programmed-cell-death.
PMID: 37152151
Front Plant Sci , IF:5.753 , 2023 , V14 : P1127197 doi: 10.3389/fpls.2023.1127197
The function of BoTCP25 in the regulation of leaf development of Chinese kale.
College of Horticulture, Fujian Agriculture and Forestry University, Fuzhou, China.; Department of Plant, Food, and Environmental Sciences, Faculty of Agriculture, Dalhousie University, Truro, NS, Canada.; Faculte des sciences et de la technologie, Institut de la Recherche Interdiciplinaire de Toulouse (IRIT-ARI), Toulouse, France.
XG Chinese kale (Brassica oleracea cv. 'XiangGu') is a variety of Chinese kale and has metamorphic leaves attached to the true leaves. Metamorphic leaves are secondary leaves emerging from the veins of true leaves. However, it remains unknown how the formation of metamorphic leaves is regulated and whether it differs from normal leaves. BoTCP25 is differentially expressed in different parts of XG leaves and respond to auxin signals. To clarify the function of BoTCP25 in XG Chinese kale leaves, we overexpressed BoTCP25 in XG and Arabidopsis, and interestingly, its overexpression caused Chinese kale leaves to curl and changed the location of metamorphic leaves, whereas heterologous expression of BoTCP25 in Arabidopsis did not show metamorphic leaves, but only an increase in leaf number and leaf area. Further analysis of the expression of related genes in Chinese kale and Arabidopsis overexpressing BoTCP25 revealed that BoTCP25 could directly bind the promoter of BoNGA3, a transcription factor related to leaf development, and induce a significant expression of BoNGA3 in transgenic Chinese kale plants, whereas this induction of NGA3 did not occur in transgenic Arabidopsis. This suggests that the regulation of Chinese kale metamorphic leaves by BoTCP25 is dependent on a regulatory pathway or elements specific to XG and that this regulatory element may be repressed or absent from Arabidopsis. In addition, the expression of miR319's precursor, a negative regulator of BoTCP25, also differed in transgenic Chinese kale and Arabidopsis. miR319's transcrips were significantly up-regulated in transgenic Chinese kale mature leaves, while in transgenic Arabidopsis, the expression of miR319 in mature leaves was kept low. In conclusion, the differential expression of BoNGA3 and miR319 in the two species may be related to the exertion of BoTCP25 function, thus partially contributing to the differences in leaf phenotypes between overexpressed BoTCP25 in Arabidopsis and Chinese kale.
PMID: 37143872
Front Plant Sci , IF:5.753 , 2023 , V14 : P1163219 doi: 10.3389/fpls.2023.1163219
Genome-wide identification of the soybean cytokinin oxidase/dehydrogenase gene family and its diverse roles in response to multiple abiotic stress.
Agricultural College, Heilongjiang Bayi Agricultural University, Daqing, Heilongjiang, China.; National Cereals Technology Engineering Research Center, Daqing, Heilongjiang, China.; Heilongjiang Bayi Agricultural University, Key Laboratory of Ministry of Agriculture and Rural Affairs of Soybean Mechanized Production, Daqing, Heilongjiang, China.; Qiqihar Branch of Heilongjiang Academy of Agricultural Sciences, Qiqihar, Heilongjiang, China.; Research Center of Saline and Alkali Land Improvement Engineering Technology in Heilongjiang Province, Daqing, Heilongjiang, China.
Cytokinin oxidase/dehydrogenase (CKX) irreversibly degrades cytokinin, regulates growth and development, and helps plants to respond to environmental stress. Although the CKX gene has been well characterized in various plants, its role in soybean remains elusive. Therefore, in this study, the evolutionary relationship, chromosomal location, gene structure, motifs, cis-regulatory elements, collinearity, and gene expression patterns of GmCKXs were analyzed using RNA-seq, quantitative real-time PCR (qRT-PCR), and bioinformatics. We identified 18 GmCKX genes from the soybean genome and grouped them into five clades, each comprising members with similar gene structures and motifs. Cis-acting elements involved in hormones, resistance, and physiological metabolism were detected in the promoter regions of GmCKXs. Synteny analysis indicated that segmental duplication events contributed to the expansion of the soybean CKX family. The expression profiling of the GmCKXs genes using qRT-PCR showed tissue-specific expression patterns. The RNA-seq analysis also indicated that GmCKXs play an important role in response to salt and drought stresses at the seedling stage. The responses of the genes to salt, drought, synthetic cytokinin 6-benzyl aminopurine (6-BA), and the auxin indole-3-acetic acid (IAA) at the germination stage were further evaluated by qRT-PCR. Specifically, the GmCKX14 gene was downregulated in the roots and the radicles at the germination stage. The hormones 6-BA and IAA repressed the expression levels of GmCKX1, GmCKX6, and GmCKX9 genes but upregulated the expression levels of GmCKX10 and GmCKX18 genes. The three abiotic stresses also decreased the zeatin content in soybean radicle but enhanced the activity of the CKX enzymes. Conversely, the 6-BA and IAA treatments enhanced the CKX enzymes' activity but reduced the zeatin content in the radicles. This study, therefore, provides a reference for the functional analysis of GmCKXs in soybean in response to abiotic stresses.
PMID: 37139113
Front Plant Sci , IF:5.753 , 2023 , V14 : P1167202 doi: 10.3389/fpls.2023.1167202
OsMYB7 determines leaf angle at the late developmental stage of lamina joints in rice.
Department of Agriculture, Forestry and Bioresources, Plant Genomics and Breeding Institute, Research Institute of Agriculture and Life Sciences, Seoul National University, Seoul, Republic of Korea.; Division of Life Sciences, Incheon National University, Incheon, Republic of Korea.
Leaf angle shapes plant architecture, allowing for optimal light interception to maximize photosynthesis and yield, and therefore is a crucial agronomic trait. Here, we show that the rice (Oryza sativa L.) R2R3-type MYB transcription factor OsMYB7 determines leaf angle in a developmental stage-specific manner. OsMYB7-overexpressing lines produced wide-angled leaves and osmyb7 knockout mutants exhibited erect leaves. This phenotype was restricted to the lamina joints at the late developmental stage. In agreement with these observations, OsMYB7 was preferentially expressed in the lamina joints of post-mature leaves. Since OsMYB7 homologs are transcriptional repressors of lignin biosynthesis, we examined whether OsMYB7 might inhibit thickening of secondary cell walls. Although OsMYB7 repressed lignin biosynthesis, it enhanced thickening of sclerenchyma cell walls by elevating cellulose contents at the lamina joints. Furthermore, we found that OsMYB7 affects endogenous auxin levels in lamina joints, and the adaxial cells of lamina joints in OsMYB7-overexpressing lines and osmyb7 knockout mutants exhibited enhanced and reduced elongation, respectively, compared to the wild type. These results suggest that OsMYB7 promotes leaf inclination partially through decreasing free auxin levels and promoting cell elongation at the adaxial side of lamina joints.
PMID: 37123839
Front Plant Sci , IF:5.753 , 2023 , V14 : P1152485 doi: 10.3389/fpls.2023.1152485
Comparative transcriptome analysis provides novel insights into molecular response of salt-tolerant and sensitive polyembryonic mango genotypes to salinity stress at seedling stage.
Division of Fruit Crops, ICAR-Indian Institute of Horticultural Research, Hesaraghatta Lakepost, Bengaluru, Karnataka, India.; Division of Biotechnology, ICAR-Indian Institute of Horticultural Research, Hesaraghatta Lakepost, Bengaluru, Karnataka, India.; Department of Botany and Microbiology, College of Science, King Saud University, Riyadh, Saudi Arabia.; School of Biological Sciences, Seoul National University, Seoul, Republic of Korea.
INTRODUCTION: Increased soil salinity in the recent years has adversely affected the productivity of mango globally. Extending the cultivation of mango in salt affected regions warrants the use of salinity tolerant/resistant rootstocks. However, the lack of sufficient genomic and transcriptomic information impedes comprehensive research at the molecular level. METHOD: We employed RNA sequencing-based transcriptome analysis to gain insight into molecular response to salt stress by using two polyembryonic mango genotypes with contrasting response to salt stress viz., salt tolerant Turpentine and salt susceptible Mylepelian. RESULTS: RNA sequencing by Novaseq6000 resulted in a total of 2795088, 17535948, 7813704 and 5544894 clean reads in Mylepelian treated (MT), Mylepelian control (MC), Turpentine treated (TT) and Turpentine control (TC) respectively. In total, 7169 unigenes annotated against all the five public databases, including NR, NT, PFAM, KOG, Swissport, KEGG and GO. Further, maximum number of differentially expressed genes were found between MT and MC (2106) followed by MT vs TT (1158) and TT and TC (587). The differentially expressed genes under different treatment levels included transcription factors (bZIP, NAC, bHLH), genes involved in Calcium-dependent protein kinases (CDPKs), ABA biosynthesis, Photosynthesis etc. Expression of few of these genes was experimentally validated through quantitative real-time PCR (qRT-PCR) and contrasting expression pattern of Auxin Response Factor 2 (ARF2), Late Embryogenesis Abundant (LEA) and CDPK genes were observed between Turpentine and Mylepelian. DISCUSSION: The results of this study will be useful in understanding the molecular mechanism underlying salt tolerance in mango which can serve as valuable baseline information to generate new targets in mango breeding for salt tolerance.
PMID: 37123820
Front Plant Sci , IF:5.753 , 2023 , V14 : P1136563 doi: 10.3389/fpls.2023.1136563
Understanding the mode of action of AgroGain((R)), a biostimulant derived from the red seaweed Kappaphycus alvarezii in the stimulation of cotyledon expansion and growth of Cucumis sativa (cucumber).
Research and Development Division, Sea6 Energy Private Limited, Centre for Cellular and Molecular Platforms, National Centre for Biological Sciences-Tata Institute of Fundamental Research, Bengaluru, Karnataka, India.; Verschuren Centre for Sustainability in Energy and the Environment, Sydney, NS, Canada.
Seaweed-based biostimulants are sustainable agriculture inputs that are known to have a multitude of beneficial effects on plant growth and productivity. This study demonstrates that Agrogain((R)) (Product code: LBS6), a Kappaphycus alvarezii-derived biostimulant induced the expansion of cucumber cotyledons. Seven days treatment of LBS6-supplementation showed a 29.2% increase in area of expanded cotyledons, as compared to the control. LBS6-treated cotyledons also showed higher amylase activity, suggesting starch to sucrose conversion was used efficiently as an energy source during expansion. To understand the mechanisms of LBS6-induced expansion, real time gene expression analysis was carried out. This revealed that LBS6-treated cotyledons differentially modulated the expression of genes involved in cell division, cell number, cell expansion and cell size. LBS6 treatment also differentially regulated the expression of those genes involved in auxin and cytokinin metabolism. Further, foliar application of LBS6 on cucumber plants being grown under hydroponic conditions showed improved plant growth as compared to the control. The total leaf area of LBS6-sprayed plants increased by 19.1%, as compared to control. LBS6-sprayed plants efficiently regulated photosynthetic quenching by reducing loss via non-photochemical and non-regulatory quenching. LBS6 applications also modulated changes in the steady-state photosynthetic parameters of the cucumber leaves. It was demonstrated that LBS6 treatment modulated the electron and proton transport related pathways which help plants to efficiently utilize the photosynthetic radiation for optimal growth. These results provide clear evidence that bioactive compounds present in LBS6 improved the growth of cucumber plants by regulating the physiological as well as developmental pathways.
PMID: 37089639
Front Plant Sci , IF:5.753 , 2023 , V14 : P1118895 doi: 10.3389/fpls.2023.1118895
Integrating omics reveals insights into tomato abaxial/adaxial leafy supplemental lighting.
College of Horticulture, Sichuan Agricultural University, Chengdu, China.; Laboratory of Crop Immune Gene Editing Technology, Chengdu NewSun Crop Science Co., Ltd., Chengdu, China.; Research Institute of Crop Germplasm Resources, Xinjiang Academy of Agricultural Sciences, Urumqi, China.
Research revealed that the abaxial leafy supplemental lighting (AB) can significantly improve the net photosynthetic rate and stomatal conductance in the leaves of tomato plants compare to the adaxial leafy supplemental lighting (AD) method. However, the underlying regulatory mechanisms are still poorly understood. Here, we conducted AB and AD on tomato and assessed transcriptomic, and proteomic changes in leaves. The result showed that under the two supplemental lighting methods, a total of 7352 genes and 152 proteins were differentially expressed. Significant differences were observed in genes expression levels and proteins abundances across multiple pathways, mainly including cell process, metabolism process, biological regulation, environment information processing, genetic information processing, metabolism, and organismal systems. Additionally, we also found that some key genes that plant hormone signaling, light perception, photosynthesis, plant fitness, and promoting fruit ripening, have increased significantly, which can explain the effect of AB on plant growth and development. Finally, through the qPCR, we determined that AB mainly up-regulate a series of auxin-responsive genes or factors, auxin polarity transport genes, gibberellin synthesis genes, cell cycle regulator genes, sugar transporters, and fleshy fruit ripening genes. These results help us to understand plant light response mechanism and discover genes which contribute to efficient light energy utilization.
PMID: 37089633
Front Plant Sci , IF:5.753 , 2023 , V14 : P1121259 doi: 10.3389/fpls.2023.1121259
Changes and transcriptome regulation of endogenous hormones during somatic embryogenesis in Ormosia henryi Prain.
College of Forestry, Guizhou University, Guiyang, Guizhou, China.; College of Life Science, Guizhou Normal University, Guiyang, Guizhou, China.
INTRODUCTION: Ormosia henryi is a rare and endangered plant growing in southern China. Somatic embryo culture is an effective measure for the rapid propagation of O. henryi. It has not been reported how regulatory genes induce somatic embryogenesis by regulating endogenous hormone changes during the process of somatic embryogenesis in O. henryi. METHODS: In this study, we analysed the endogenous hormone levels and transcriptome data of nonembryogenic callus (NEC), embryogenic callus (EC), globular embryo (GE) and cotyledon embryo (CE) in O. henryi. RESULTS: The results showed that the indole-3-acetic acid (IAA) content was higher and the cytokinins (CKs) content was lower in EC than in NEC, and the gibberellins (GAs) and abscisic acid (ABA) contents were significantly higher in NEC than in EC. The contents of IAA, CKs, GAs and ABA increased significantly with EC development. The expression patterns of differentially expressed genes (DEGs) involved in the biosynthesis and signal transduction of auxin (AUX) (YUCCA and SAUR), CKs (B-ARR), GAs (GA3ox, GA20ox, GID1 and DELLA) and ABA (ZEP, ABA2, AAO3, CYP97A3, PYL and ABF) were consistent with the levels of endogenous hormones during somatic embryogenesis (SE). In this study, 316 different transcription factors (TFs) regulating phytohormones were detected during SE. AUX/IAA were downregulated in the process of EC formation and GE differentiation into CE, but other TFs were upregulated and downregulated. CONCLUSION: Therefore, we believe that relatively high IAA content and low CKs, GAs and ABA contents contribute to EC formation. The differential expression of AUX, CKs, GAs and ABA biosynthesis and signal transduction genes affected the endogenous hormone levels at different stages of SE in O. henryi. The downregulated expression of AUX/IAA inhibited NEC induction, promoted EC formation and GE differentiation into CE.
PMID: 37077643
Theor Appl Genet , IF:5.699 , 2023 Apr , V136 (5) : P112 doi: 10.1007/s00122-023-04350-w
Epistatic interaction between CsCEN and CsSHBY in regulating indeterminate/determinate growth of lateral branch in cucumber.
National Key Laboratory of Crop Genetics and Germplasm Enhancement and Utilization, College of Horticulture, Nanjing Agricultural University, Nanjing, 210095, China.; Department of Plant Science, Chuka University, P.O. Box 109-60400, Chuka, Kenya.; College of Horticulture and Landscape, Henan Institute of Science and Technology, Xinxiang, 453000, China. junguo1020@163.com.; National Key Laboratory of Crop Genetics and Germplasm Enhancement and Utilization, College of Horticulture, Nanjing Agricultural University, Nanjing, 210095, China. liji1981@njau.edu.cn.; National Key Laboratory of Crop Genetics and Germplasm Enhancement and Utilization, College of Horticulture, Nanjing Agricultural University, Nanjing, 210095, China. jfchen@njau.edu.cn.
Two genetic loci, det-ma (CsCEN) and det-lb, showed epistatic interaction on indeterminate/determinate growth of LB in cucumber. CsSHBY was identified as the candidate gene for det-lb locus. Plant architecture depends on the spatial regulation of meristems from both main axis (MA) and lateral branches (LBs). Fate (indeterminate or determinate) of these meristems is a crucial source of architectural diversity determining crop productivity and management. CENTRORADIALIS/TERMINAL FLOWER 1/SELF-PRUNING (CETS) gene family have been well known as pivotal regulators for indeterminate/determinate growth of MA. Nevertheless, genes that regulate LB indeterminacy/determinacy remained unclear. Cucumber (Cucumis sativus L.) has typical monopodial growth and multiple lateral branches. Both MA and LBs had indeterminate or determinate growth, and indeterminate/determinate growth of LB was controlled by two distinct loci, det-ma (CsCEN) and det-lb. In our study, based on bulked segregant analysis (BSA) method, the det-lb locus was mapped on a 60.6 kb region on chromosome 1 harboring only one gene CsaV3_1G044330, which encoded a putative vacuolar-sorting protein (designated as CsSHBY). Multipoint mutations in CsSHBY were identified in D082 and D226, compared with CCMC, including nonsynonymous SNP mutations and a 6-bp deletion in exons. Further, qPCR showed that CsSHBY was highly expressed in lateral bud of CCMC, suggesting that CsSHBY might play an active role in regulating indeterminate/determinate growth of LB. Genetic analyses showed that det-ma (CsCEN) had an epistatic effect on det-lb (CsSHBY), and CsCEN could activate CsSHBY promoter by Dual luciferase and GUS activity assays. Meanwhile, Cscen or Csshby was found to influence auxin contents and CsYUCs and CsPINs expression levels. These findings provided new insights into precisely optimizing plant architecture for yield improvements.
PMID: 37052719
Front Microbiol , IF:5.64 , 2023 , V14 : P1152597 doi: 10.3389/fmicb.2023.1152597
Biocontrol and plant growth promoting traits of two avocado rhizobacteria are orchestrated by the emission of diffusible and volatile compounds.
Red de Estudios Moleculares Avanzados, Instituto de Ecologia, A.C., Xalapa, Veracruz, Mexico.; CONACyT - Escuela Nacional de Estudios Superiores, Unidad Morelia, Laboratorio Nacional de Analisis y Sintesis Ecologica, Universidad Nacional Autonoma de Mexico, Morelia, Michoacan, Mexico.; CONACyT - Red de Diversidad Biologica del Occidente Mexicano, Centro Regional del Bajio, Instituto de Ecologia, A.C., Patzcuaro, Michoacan, Mexico.; Facultad de Medicina, Universidad Nacional Autonoma de Mexico, Ciudad de Mexico, Mexico.; Escuela Nacional de Estudios Superiores Unidad Morelia, Laboratorio Nacional de Analisis y Sintesis Ecologica, Universidad Nacional Autonoma de Mexico, Morelia, Mexico.; Red de Diversidad Biologica del Occidente Mexicano, Centro Regional del Bajio, Instituto de Ecologia, A.C., Patzcuaro, Michoacan, Mexico.
Avocado (Persea americana Mill.) is a tree crop of great social and economic importance. However, the crop productivity is hindered by fast-spreading diseases, which calls for the search of new biocontrol alternatives to mitigate the impact of avocado phytopathogens. Our objectives were to evaluate the antimicrobial activity of diffusible and volatile organic compounds (VOCs) produced by two avocado rhizobacteria (Bacillus A8a and HA) against phytopathogens Fusarium solani, Fusarium kuroshium, and Phytophthora cinnamomi, and assess their plant growth promoting effect in Arabidopsis thaliana. We found that, in vitro, VOCs emitted by both bacterial strains inhibited mycelial growth of the tested pathogens by at least 20%. Identification of bacterial VOCs by gas chromatography coupled to mass spectrometry (GC-MS) showed a predominance of ketones, alcohols and nitrogenous compounds, previously reported for their antimicrobial activity. Bacterial organic extracts obtained with ethyl acetate significantly reduced mycelial growth of F. solani, F. kuroshium, and P. cinnamomi, the highest inhibition being displayed by those from strain A8a (32, 77, and 100% inhibition, respectively). Tentative identifications carried out by liquid chromatography coupled to accurate mass spectrometry of diffusible metabolites in the bacterial extracts, evidenced the presence of some polyketides such as macrolactins and difficidin, hybrid peptides including bacillaene, and non-ribosomal peptides such as bacilysin, which have also been described in Bacillus spp. for antimicrobial activities. The plant growth regulator indole-3-acetic acid was also identified in the bacterial extracts. In vitro assays showed that VOCs from strain HA and diffusible compounds from strain A8a modified root development and increased fresh weight of A. thaliana. These compounds differentially activated several hormonal signaling pathways involved in development and defense responses in A. thaliana, such as auxin, jasmonic acid (JA) and salicylic acid (SA); genetic analyses suggested that developmental stimulation of the root system architecture by strain A8a was mediated by the auxin signaling pathway. Furthermore, both strains were able to enhance plant growth and decreased the symptoms of Fusarium wilt in A. thaliana when soil-inoculated. Collectively, our results evidence the potential of these two rhizobacterial strains and their metabolites as biocontrol agents of avocado pathogens and as biofertilizers.
PMID: 37206331
Front Microbiol , IF:5.64 , 2023 , V14 : P1096754 doi: 10.3389/fmicb.2023.1096754
Complete genome analysis of sugarcane root associated endophytic diazotroph Pseudomonas aeruginosa DJ06 revealing versatile molecular mechanism involved in sugarcane development.
College of Life Sciences and Engineering, Hexi University, Zhangye, Gansu, China.; Key Laboratory of Sugarcane Biotechnology and Genetic Improvement (Guangxi), Ministry of Agriculture, Guangxi Key Laboratory of Sugarcane Genetic Improvement, Sugarcane Research Institute, Guangxi Academy of Agricultural Sciences, Nanning, Guangxi, China.; College of Agriculture, Guangxi University, Nanning, Guangxi, China.; Microbiology Institute, Guangxi Academy of Agricultural Sciences, Nanning, Guangxi, China.
Sugarcane is an important sugar and bioenergy source and a significant component of the economy in various countries in arid and semiarid. It requires more synthetic fertilizers and fungicides during growth and development. However, the excess use of synthetic fertilizers and fungicides causes environmental pollution and affects cane quality and productivity. Plant growth-promoting bacteria (PGPB) indirectly or directly promote plant growth in various ways. In this study, 22 PGPB strains were isolated from the roots of the sugarcane variety GT42. After screening of plant growth-promoting (PGP) traits, it was found that the DJ06 strain had the most potent PGP activity, which was identified as Pseudomonas aeruginosa by 16S rRNA gene sequencing. Scanning electron microscopy (SEM) and green fluorescent protein (GFP) labeling technology confirmed that the DJ06 strain successfully colonized sugarcane tissues. The complete genome sequencing of the DJ06 strain was performed using Nanopore and Illumina sequencing platforms. The results showed that the DJ06 strain genome size was 64,90,034 bp with a G+C content of 66.34%, including 5,912 protein-coding genes (CDSs) and 12 rRNA genes. A series of genes related to plant growth promotion was observed, such as nitrogen fixation, ammonia assimilation, siderophore, 1-aminocyclopropane-1-carboxylic acid (ACC), deaminase, indole-3-acetic acid (IAA) production, auxin biosynthesis, phosphate metabolism, hydrolase, biocontrol, and tolerance to abiotic stresses. In addition, the effect of the DJ06 strain was also evaluated by inoculation in two sugarcane varieties GT11 and B8. The length of the plant was increased significantly by 32.43 and 12.66% and fresh weight by 89.87 and 135.71% in sugarcane GT11 and B8 at 60 days after inoculation. The photosynthetic leaf gas exchange also increased significantly compared with the control plants. The content of indole-3-acetic acid (IAA) was enhanced and gibberellins (GA) and abscisic acid (ABA) were reduced in response to inoculation of the DJ06 strain as compared with control in two sugarcane varieties. The enzymatic activities of oxidative, nitrogen metabolism, and hydrolases were also changed dramatically in both sugarcane varieties with inoculation of the DJ06 strain. These findings provide better insights into the interactive action mechanisms of the P. aeruginosa DJ06 strain and sugarcane plant development.
PMID: 37152763
Pest Manag Sci , IF:4.845 , 2023 May doi: 10.1002/ps.7541
Nontarget-site resistance due to rapid physiological response in 2,4-D resistant Conyza sumatrensis: reduced 2,4-D translocation and auxin-induced gene expression.
Federal Rural University of Rio de Janeiro, Department of Crop, Seropedica, Brazil.; Colorado State University, Department of Agricultural Biology, Fort Collins, Colorado, USA.; Corteva Agriscience, Field Scientist, Sao Paulo, Brazil.
BACKGROUND: Resistance to 2,4-Dichlorophenoxyacetic acid (2,4-D) has been reported in several weed species since the 1950s; however, a biotype of Conyza sumatrensis showing a novel physiology of the rapid response minutes after herbicide application was reported in 2017. The objective of this research was to investigate the mechanisms of resistance and identify transcripts associated with the rapid physiological response of C. sumatrensis to 2,4-D herbicide. RESULTS: Differences were found in 2,4-D absorption between the resistant and susceptible biotypes. Herbicide translocation was reduced in the resistant biotype compared to the susceptible. In resistant plants 98.8% of [(14) C] 2,4-D was found in the treated leaf, whereas approximately 13% translocated to other plant parts in the susceptible biotype at 96 h after treatment. Resistant plants did not metabolize [(14) C] 2,4-D and had only intact [(14) C] 2,4-D at 96 h after application, whereas susceptible plants metabolized [(14) C] 2,4-D into four detected metabolites, consistent with reversible conjugation metabolites found in other 2,4-D sensitive plant species. Pre-treatment with the cytochrome P450 inhibitor malathion did not enhance 2,4-D sensitivity in either biotype. Following treatment with 2,4-D, resistant plants showed increased expression of transcripts within plant defense response and hypersensitivity pathways, whereas both sensitive and resistant plants showed increased expression of auxin-response transcripts. CONCLUSION: Our results demonstrate that reduced 2,4-D translocation contributes to resistance in the C. sumatrensis biotype. The reduction in 2,4-D transport is likely to be a consequence of the rapid physiological response to 2,4-D in resistant C. sumatrensis. Resistant plants had increased expression of auxin-responsive transcripts, indicating that a target-site mechanism is unlikely. (c) 2023 Society of Chemical Industry.
PMID: 37178347
Pest Manag Sci , IF:4.845 , 2023 Apr , V79 (4) : P1305-1315 doi: 10.1002/ps.7294
The differential binding and biological efficacy of auxin herbicides.
School of Life Sciences, University of Warwick, Coventry, UK.; Corteva Agriscience, Crop Protection Discovery & Development, Indianapolis, Indiana, USA.
BACKGROUND: Auxin herbicides have been used for selective weed control for 75 years and they continue to be amongst the most widely used weed control agents globally. The auxin herbicides fall into five chemical classes, with two herbicides not classified, and in all cases it is anticipated that recognition in the plant starts with binding to the Transport Inhibitor Response 1 (TIR1) family of auxin receptors. There is evidence that some classes of auxins act selectively with certain clades of receptors, although a comprehensive structure-activity relationship has not been available. RESULTS: Using purified receptor proteins to measure binding efficacy we have conducted quantitative structure activity relationship (qSAR) assays using representative members of the three receptor clades in Arabidopsis, TIR1, AFB2 and AFB5. Complementary qSAR data for biological efficacy at the whole-plant level using root growth inhibition and foliar phytotoxicity assays have also been analyzed for each family of auxin herbicides, including for the afb5-1 receptor mutant line. CONCLUSIONS: Comparisons of all these assays highlight differences in receptor selectivity and some systematic differences between results for binding in vitro and activity in vivo. The results could provide insights into weed spectrum differences between the different classes of auxin herbicides, as well as the potential resistance and cross-resistance implications for this herbicide class. (c) 2022 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.
PMID: 36458868
Plant Sci , IF:4.729 , 2023 Jul , V332 : P111726 doi: 10.1016/j.plantsci.2023.111726
Short-term exposition to acute cadmium toxicity induces the loss of root gravitropic stimuli perception through PIN2-mediated auxin redistribution in Arabidopsis thaliana (L.) Heynh.
Department of Agricultural and Environmental Sciences, University of Milano, Milan 20133, Italy.; Department of Biology, Ecology and Earth Sciences (DiBEST), University of Calabria, Arcavacata of Rende, CS 87036, Italy.; Universidade de Vigo, Departamento de Bioloxia Vexetal e Ciencias do Solo, Facultade de Bioloxia, Campus Lagoas-Marcosende s/n, 36310 Vigo, Spain.; Department of Biology, Ecology and Earth Sciences (DiBEST), University of Calabria, Arcavacata of Rende, CS 87036, Italy. Electronic address: leonardo.bruno@unical.it.
Cadmium (Cd), one of the most widespread and water-soluble polluting heavy metals, has been widely studied on plants, even if the mechanisms underlying its phytotoxicity remain elusive. Indeed, most experiments are performed using extensive exposure time to the toxicants, not observing the primary targets affected. The present work studied Cd effects on Arabidopsis thaliana (L.) Heynh's root apical meristem (RAM) exposed for short periods (24 h and 48 h) to acute phytotoxic concentrations (100 and 150 microM). The effects were studied through integrated morpho-histological, molecular, pharmacological and metabolomic analyses, highlighting that Cd inhibited primary root elongation by affecting the meristem zone via altering cell expansion. Moreover, Cd altered Auxin accumulation in RAM and affected PINs polar transporters, particularly PIN2. In addition, we observed that high Cd concentration induced accumulation of reactive oxygen species (ROS) in roots, which resulted in an altered organization of cortical microtubules and the starch and sucrose metabolism, altering the statolith formation and, consequently, the gravitropic root response. Our results demonstrated that short Cd exposition (24 h) affected cell expansion preferentially, altering auxin distribution and inducing ROS accumulation, which resulted in an alteration of gravitropic response and microtubules orientation pattern.
PMID: 37149227
Plant Sci , IF:4.729 , 2023 Jul , V332 : P111718 doi: 10.1016/j.plantsci.2023.111718
Indole-3-acetaldoxime delays root iron-deficiency responses and modify auxin homeostasis in Medicago truncatula.
Department of Pomology, Aula Dei Experimental Station, Consejo Superior de Investigaciones Cientificas (CSIC), Avda. de Montanana 1005, E-50059 Zaragoza, Spain.; Institute for Multidisciplinary Research in Applied Biology (IMAB), Department of Sciences, Public University of Navarre (UPNA), Avda. de Pamplona 123, E-31192 Mutilva, Spain.; Institute for Advanced Materials and Mathematics (INAMAT2), Department of Sciences, Public University of Navarre (UPNA), Campus de Arrosadia, E-31006 Pamplona, Spain.; Department of Pomology, Aula Dei Experimental Station, Consejo Superior de Investigaciones Cientificas (CSIC), Avda. de Montanana 1005, E-50059 Zaragoza, Spain. Electronic address: aoiz@eead.csic.es.
Iron (Fe) is an essential plant micronutrient, being a major limiting growth factor in calcareous soils. To increase Fe uptake, plants induce lateral roots growth, the expression of a Fe(III)-chelate reductase (FCR), a Fe(II)-transporter and a H(+)-ATPase and the secretion of flavins. Furthermore, auxin hormone family is involved in the Fe-deficiency responses but the action mechanism remains elusive. In this work, we evaluated the effect of the auxin-precursor indole-3-acetaldoxime (IAOx) on hydroponically grown Medicago truncatula plants under different Fe conditions. Upon 4-days of Fe starvation, the pH of the nutrient solution decreased, while both the FCR activity and the presence of flavins increased. Exogenous IAOx increased lateral roots growth contributing to superroot phenotype, decreased chlorosis, and delayed up to 3-days the pH-decrease, the FCR-activity increase, and the presence of flavins, compared to Fe-deficient plants. Gene expression levels were in concordance with the physiological responses. RESULTS: showed that IAOx was immediately transformed to IAN in roots and shoots to maintain auxin homeostasis. IAOx plays an active role in iron homeostasis delaying symptoms and responses in Fe-deficient plants. We may speculate that IAOx or its derivatives remobilize Fe from root cells to alleviate Fe-deficiency. Overall, these results point out that the IAOx-derived phenotype may have advantages to overcome nutritional stresses.
PMID: 37105378
Plant Sci , IF:4.729 , 2023 Jul , V332 : P111699 doi: 10.1016/j.plantsci.2023.111699
Role of EIN2-mediated ethylene signaling in regulating petal senescence, abscission, reproductive development, and hormonal crosstalk in tobacco.
Department of Biology, University of Texas Rio Grande Valley, 1201 W. University Dr, Edinburg, TX 78539, USA. Electronic address: manohar.chakrabarti@utrgv.edu.; Department of Biology, University of Texas Rio Grande Valley, 1201 W. University Dr, Edinburg, TX 78539, USA.
Ethylene plays a pivotal role in a wide range of developmental, physiological, and defense processes in plants. EIN2 (ETHYLENE INSENSITIVE2) is a key player in the ethylene signaling pathway. To characterize the role of EIN2 in processes, such as petal senescence, where it has been found to play important roles along with various other developmental and physiological processes, the tobacco (Nicotiana tabacum) ortholog of EIN2 (NtEIN2) was isolated and NtEIN2 silenced transgenic lines were generated using RNA interference (RNAi). Silencing of NtEIN2 compromised plant defense against pathogens. NtEIN2 silenced lines displayed significant delays in petal senescence, and pod maturation, and adversely affected pod and seed development. This study further dissected the petal senescence in ethylene insensitive lines, that displayed alteration in the pattern of petal senescence and floral organ abscission. Delay in petal senescence was possibly because of delayed aging processes within petal tissues. Possible crosstalk between EIN2 and AUXIN RESPONSE FACTOR 2 (ARF2) in regulating the petal senescence process was also investigated. Overall, these experiments indicated a crucial role for NtEIN2 in controlling diverse developmental and physiological processes, especially in petal senescence.
PMID: 37028457
Plant Sci , IF:4.729 , 2023 Jun , V331 : P111686 doi: 10.1016/j.plantsci.2023.111686
Conservation and divergence of flg22, pep1 and nlp20 in activation of immune response and inhibition of root development.
College of Life Sciences, Sichuan Agricultural University, Ya'an, Sichuan, PR China.; College of Horticulture, FAFU-UCR Joint Center and Fujian Provincial Key Laboratory of Haixia Applied Plant Systems Biology, Fujian Agriculture and Forestry University, Fuzhou 350002, PR China.; Lusyno Biotech Ltd., Chengdu, Sichuan, PR China.; College of Horticulture, FAFU-UCR Joint Center and Fujian Provincial Key Laboratory of Haixia Applied Plant Systems Biology, Fujian Agriculture and Forestry University, Fuzhou 350002, PR China. Electronic address: wus@fafu.edu.cn.; College of Life Sciences, Sichuan Agricultural University, Ya'an, Sichuan, PR China. Electronic address: yicai@sicau.edu.cn.
Many pattern-recognition receptors (PRRs) and their corresponding ligands have been identified. However, it is largely unknown how similar and different these ligands are in inducing plant innate immunity and affecting plant development. In this study, we examined three well characterized ligands in Arabidopsis thaliana, namely flagellin 22 (flg22), plant elicitor peptide 1 (pep1) and a conserved 20-amino-acid fragment found in most necrosis and ethylene-inducing peptide 1-like proteins (nlp20). Our quantitative analyses detected the differences in amplitude in the early immune responses of these ligands, with nlp20-induced responses typically being slower than those mediated by flg22 and pep1. RNA sequencing showed the shared differentially expressed genes (DEGs) was mostly enriched in defense response, whereas nlp20-regulated genes represent only a fraction of those genes differentially regulated by flg22 and pep1. The three elicitors all inhibited primary root growth, especially pep1, which inhibited both auxin transport and signaling pathway. In addition, pep1 significantly inhibited the cell division and genes involved in cell cycle. Compared with flg22 and nlp20, pep1 induced much stronger expression of its receptor in roots, suggesting a potential positive feedback regulation in the activation of immune response. Despite PRRs and their co-receptor BAK1 were necessary for both PAMP induced immune response and root growth inhibition, bik1 mutant only showed impaired defense response but relatively normal root growth inhibition, suggesting BIK1 acts differently in these two biological processes.
PMID: 36963637
Plant Sci , IF:4.729 , 2023 Jun , V331 : P111677 doi: 10.1016/j.plantsci.2023.111677
Dysfunction of GmVPS8a causes compact plant architecture in soybean.
Soybean Research Institute, Key Laboratory of Biology and Genetic Improvement of Soybean, National Center for Soybean Improvement (Ministry of Agriculture), National Key Laboratory for Crop Genetics and Germplasm Enhancement, Nanjing Agricultural University, Nanjing 210095, China.; National Soybean Improvement Center Shijiazhuang Sub-Center, North China Key Laboratory of Biology and Genetic Improvement of Soybean, Ministry of Agriculture, Laboratory of Crop Genetics and Breeding of Hebei, Cereal & Oil Crop Institute, Hebei Academy of Agricultural and Forestry Sciences, Shijiazhuang, China.; The National Key Facility for Crop Gene Resources and Genetic Improvement (NFCRI), Institute of Crop Science, Chinese Academy of Agricultural Sciences, Beijing, China. Electronic address: liubin05@caas.cn.; Soybean Research Institute, Key Laboratory of Biology and Genetic Improvement of Soybean, National Center for Soybean Improvement (Ministry of Agriculture), National Key Laboratory for Crop Genetics and Germplasm Enhancement, Nanjing Agricultural University, Nanjing 210095, China. Electronic address: tjzhao@njau.edu.cn.
Vacuolar Protein Sorting 8 (Vps8) protein is a specific subunit of the class C core vacuole/endosome tethering (CORVET) complex that plays a key role in endosomal trafficking in yeast (Saccharomyces cerevisiae). However, its functions remain largely unclear in plant vegetative growth. Here, we identified a soybean (Glycine max) T4219 mutant characterized with compact plant architecture. Map-based cloning targeted to a candidate gene GmVPS8a (Glyma.07g049700) and further found that two nucleotides deletion in the first exon of GmVPS8a causes a premature termination of the encoded protein in the T4219 mutant. Its functions were validated by CRISPR/Cas9-engineered mutation in the GmVPS8a gene that recapitulated the T4219 mutant phenotypes. Furthermore, NbVPS8a-silenced tobacco (Nicotiana benthamiana) plants exhibited similar phenotypes to the T4219 mutant, suggesting its conserved roles in plant growth. The GmVPS8a is widely expressed in multiple organs and its protein interacts with GmAra6a and GmRab5a. Combined analysis of transcriptomic and proteomic data revealed that dysfunction of GmVPS8a mainly affects pathways on auxin signal transduction, sugar transport and metabolism, and lipid metabolism. Collectively, our work reveals the function of GmVPS8a in plant architecture, which may extend a new way for genetic improvement of ideal plant-architecture breeding in soybean and other crops.
PMID: 36931563
Plant Sci , IF:4.729 , 2023 May , V330 : P111666 doi: 10.1016/j.plantsci.2023.111666
Genome-wide identification and characterization of long non-coding RNA in barley roots in response to Piriformospora indica colonization.
School of Chemical Engineering and Technology, Hebei University of Technology, Tianjin 300130, China. Electronic address: liangli@hebut.edu.cn.; School of Chemical Engineering and Technology, Hebei University of Technology, Tianjin 300130, China.; School of Chemical Engineering and Technology, Hebei University of Technology, Tianjin 300130, China. Electronic address: jackeikee@hebut.edu.cn.
Currently, there is very limited information about long noncoding RNAs (lncRNAs) found in barley. It remains unclear whether barley lncRNAs are responsive to Piriformospora indica (P. indica) colonization.We found that barley roots exhibited fast development and that large roots branched after P. indica colonization. Genome-wide high-throughput RNA-seq and bioinformatic analysis showed that 4356 and 5154 differentially expressed LncRNAs (DELs) were found in response to P. indica at 3 and 7 days after colonization (dai), respectively, and 2456 DELs were found at 7 dai compared to 3 dai. Based on the coexpression correlation of lncRNAmRNA, we found that 98.6% of lncRNAs were positively correlated with 3430 mRNAs at 3 dai and 7 dai. Further GO analysis showed that 30 lncRNAs might be involved in the regulation of gene transcription; 23 lncRNAs might participate in cell cycle regulation. Moreover, the metabolite analysis indicated that chlorophyll a, sucrose, protein, gibberellin, and auxin were in accordance with the results of the transcriptome, and the respective lncRNAs were positively correlated with these target RNAs. Gene silencing suggested that lncRNA TCONS_00262342 is probably a key regulator of GA(3) synthesis pathway, which participates in P. indica and barley interactions. We concluded that acting as a molecular material basis and resource, lncRNAs respond to P. indica colonization by regulating metabolite content in barley and coordinate the complex regulatory process of higher life by constructing highly positive correlations with their target mRNAs.
PMID: 36858207
Plant Sci , IF:4.729 , 2023 May , V330 : 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.
National Key Laboratory for Germplasm Innovation and Utilization of Horticultural Crops, Huazhong Agricultural University, Wuhan, Hubei, 430070, China.; Vegetable Research Institute, Guangxi Academy of Agricultural Sciences, Nanning, Guangxi, 530007, China.; Department of Plant Sciences, University of Idaho, Moscow, ID 83844, USA.; National Key Laboratory for Germplasm Innovation and Utilization of Horticultural Crops, Huazhong Agricultural University, Wuhan, Hubei, 430070, 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
Front Genet , IF:4.599 , 2023 , V14 : P1193953 doi: 10.3389/fgene.2023.1193953
Genome-wide identification, evolution and expression profiles analysis of bHLH gene family in Castanea mollissima.
Engineering Research Center of Chestnut Industry Technology, Ministry of Education, Hebei Normal University of Science and Technology, Qinhuangdao, Hebei, China.; Hebei Collaborative Innovation Center of Chestnut Industry, Qinhuangdao, Hebei, China.; Hebei Key Laboratory of Horticultural Germplasm Excavation and Innovative Utilization, Qinhuangdao, Hebei, China.
The basic helix-loop-helix (bHLH) transcription factors (TFs) gene family is an important gene family in plants, and participates in regulation of plant apical meristem growth, metabolic regulation and stress resistance. However, its characteristics and potential functions have not been studied in chestnut (Castanea mollissima), an important nut with high ecological and economic value. In the present study, 94 CmbHLHs were identified in chestnut genome, of which 88 were unevenly distributed on chromosomes, and other six were located on five unanchored scaffolds. Almost all CmbHLH proteins were predicted in the nucleus, and subcellular localization demonstrated the correctness of the above predictions. Based on the phylogenetic analysis, all of the CmbHLH genes were divided into 19 subgroups with distinct features. Abundant cis-acting regulatory elements related to endosperm expression, meristem expression, and responses to gibberellin (GA) and auxin were identified in the upstream sequences of CmbHLH genes. This indicates that these genes may have potential functions in the morphogenesis of chestnut. Comparative genome analysis showed that dispersed duplication was the main driving force for the expansion of the CmbHLH gene family inferred to have evolved through purifying selection. Transcriptome analysis and qRT-PCR experiments showed that the expression patterns of CmbHLHs were different in different chestnut tissues, and revealed some members may have potential functions in chestnut buds, nuts, fertile/abortive ovules development. The results from this study will be helpful to understand the characteristics and potential functions of the bHLH gene family in chestnut.
PMID: 37252667
Plant Cell Rep , IF:4.57 , 2023 May doi: 10.1007/s00299-023-03030-9
The SMC5/6 complex subunit MMS21 regulates stem cell proliferation in rice.
College of Agriculture, Nanjing Agricultural University, Nanjing, 210095, China.; Key Laboratory of Crop Physiology Ecology and Production Management, Ministry of Agriculture, Nanjing, 210095, China.; Jiangsu Collaborative Innovation Centre for Modern Crop Production, Nanjing, 210095, China.; College of Agriculture, Nanjing Agricultural University, Nanjing, 210095, China. dingcq@njau.edu.cn.; Key Laboratory of Crop Physiology Ecology and Production Management, Ministry of Agriculture, Nanjing, 210095, China. dingcq@njau.edu.cn.; Jiangsu Collaborative Innovation Centre for Modern Crop Production, Nanjing, 210095, China. dingcq@njau.edu.cn.
SMC5/6 complex subunit OsMMS21 is involved in cell cycle and hormone signaling and required for stem cell proliferation during shoot and root development in rice. The structural maintenance of chromosome (SMC)5/6 complex is required for nucleolar integrity and DNA metabolism. Moreover, METHYL METHANESULFONATE SENSITIVITY GENE 21 (MMS21), a SUMO E3 ligase that is part of the SMC5/6 complex, is essential for the root stem cell niche and cell cycle transition in Arabidopsis. However, its specific role in rice remains unclear. Here, OsSMC5 and OsSMC6 single heterozygous mutants were generated using CRISPR/Cas9 technology to elucidate the function of SMC5/6 subunits, including OsSMC5, OsSMC6, and OsMMS21, in cell proliferation in rice. ossmc5/ + and ossmc6/ + heterozygous single mutants did not yield homozygous mutants in their progeny, indicating that OsSMC5 and OsSMC6 both play necessary roles during embryo formation. Loss of OsMMS21 caused severe defects in both the shoot and roots in rice. Transcriptome analysis showed a significant decrease in the expression of genes involved in auxin signaling in the roots of osmms21 mutants. Moreover, the expression levels of the cycB2-1 and MCM genes, which are involved the cell cycle, were significantly lower in the shoots of the mutants, indicating that OsMMS21 was involved in both hormone signaling pathways and the cell cycle. Overall, these findings indicate that the SUMO E3 ligase OsMMS21 is required for both shoot and root stem cell niches, improving the understanding of the function of the SMC5/6 complex in rice.
PMID: 37178216
Plant Cell Rep , IF:4.57 , 2023 May doi: 10.1007/s00299-023-03025-6
Transcription elongation factors OsSPT4 and OsSPT5 are essential for rice growth and development and act with APO2.
College of Agriculture, Nanjing Agricultural University, Nanjing, 210095, People's Republic of China.; Key Laboratory of Crop Physiology Ecology and Production Management, Ministry of Agriculture, Nanjing, 210095, People's Republic of China.; Collaborative Innovation Center for Modern Crop Production Co-Sponsored by Province and Ministry, Nanjing, 210095, People's Republic of China.; College of Agriculture, Nanjing Agricultural University, Nanjing, 210095, People's Republic of China. dingcq@njau.edu.cn.; Key Laboratory of Crop Physiology Ecology and Production Management, Ministry of Agriculture, Nanjing, 210095, People's Republic of China. dingcq@njau.edu.cn.; Collaborative Innovation Center for Modern Crop Production Co-Sponsored by Province and Ministry, Nanjing, 210095, People's Republic of China. dingcq@njau.edu.cn.
The transcription elongation factor SPT4/SPT5 complex is essential for rice vegetative and reproductive growth and that OsSPT5-1, with its interactor APO2, is involved in multiple phytohormone pathways. The SPT4/SPT5 complex is a transcription elongation factor that regulates the processivity of transcription elongation. However, our understanding of the role of SPT4/SPT5 complex in developmental regulation remains limited. Here, we identified three SPT4/SPT5 genes (OsSPT4, OsSPT5-1, and OsSPT5-2) in rice, and investigated their roles in vegetative and reproductive growth. These genes are highly conserved with their orthologs in other species. OsSPT4 and OsSPT5-1 are widely expressed in various tissues. By contrast, OsSPT5-2 is expressed at a relatively low level, which could cause osspt5-2 null mutants have no phenotypes. Loss-of-function mutants of OsSPT4 and OsSPT5-1 could not be obtained; their heterozygotes showed severe reproductive growth defects. An incomplete mutant line (osspt5-1#12) displayed gibberellin-related dwarfed defects and a weak root system at an early vegetative phase, and a short life cycle in different planting environments. Furthermore, OsSPT5-1 interacts with the transcription factor ABERRANT PANICLE ORGANIZATION 2 (APO2) and plays a similar role in regulating the growth of rice shoots. RNA sequencing analysis verified that OsSPT5-1 is involved in multiple phytohormone pathways, including gibberellin, auxin, and cytokinin. Therefore, the SPT4/SPT5 complex is essential for both vegetative and reproductive growth in rice.
PMID: 37148321
Plant Cell Rep , IF:4.57 , 2023 Apr doi: 10.1007/s00299-023-03019-4
A methane-cGMP module positively influences adventitious rooting.
College of Life Sciences, Laboratory Center of Life Sciences, Nanjing Agricultural University, Nanjing, 210095, China.; Institute of Botany, Jiangsu Province and Chinese Academy of Sciences, Nanjing, 210014, China.; College of Life Sciences, Laboratory Center of Life Sciences, Nanjing Agricultural University, Nanjing, 210095, China. wbshenh@njau.edu.cn.
Endogenous cGMP operates downstream of CH(4) control of adventitious rooting, following by the regulation in the expression of cell cycle regulatory and auxin signaling-related genes. Methane (CH(4)) is a natural product from plants and microorganisms. Although exogenously applied CH(4) and cyclic guanosine monophosphate (cGMP) are separately confirmed to be involved in the control of adventitious root (AR) formation, the possible interaction still remains elusive. Here, we observed that exogenous CH(4) not only rapidly promoted cGMP synthesis through increasing the activity of guanosine cyclase (GC), but also induced cucumber AR development. These responses were obviously impaired by the removal of endogenous cGMP with two GC inhibitors. Anatomical evidence showed that the emerged stage (V) among AR primordia development might be the main target of CH(4)-cGMP module. Genetic evidence revealed that the transgenic Arabidopsis that overexpressed the methyl-coenzyme M reductase gene (MtMCR) from Methanobacterium thermoautotrophicum not only increased-cGMP production, but also resulted in a pronounced AR development compared to wild-type (WT), especially with the addition of CH(4) or the cell-permeable cGMP derivative 8-Br-cGMP. qPCR analysis confirmed that some marker genes associated with cell cycle regulatory and auxin signaling were closely related to the brand-new CH(4)-cGMP module in AR development. Overall, our results clearly revealed an important function of cGMP in CH(4) governing AR formation by modulating auxin-dependent pathway and cell cycle regulation.
PMID: 37084115
Plant Cell Rep , IF:4.57 , 2023 Jun , V42 (6) : P961-974 doi: 10.1007/s00299-023-03013-w
Abscisic acid in plants under abiotic stress: crosstalk with major phytohormones.
Department of Biotechnology, St. Xavier's College (Autonomous), 30 Mother Teresa Sarani, Kolkata, 700016, West Bengal, India.; Discipline of Life Sciences, School of Sciences, Indira Gandhi National Open University, Maidan Garhi, New Delhi, 110068, India. aryadeep.rc@gmail.com.
Extensive crosstalk exists among ABA and different phytohormones that modulate plant tolerance against different abiotic stress. Being sessile, plants are exposed to a wide range of abiotic stress (drought, heat, cold, salinity and metal toxicity) that exert unwarranted threat to plant life and drastically affect growth, development, metabolism, and yield of crops. To cope with such harsh conditions, plants have developed a wide range of protective phytohormones of which abscisic acid plays a pivotal role. It controls various physiological processes of plants such as leaf senescence, seed dormancy, stomatal closure, fruit ripening, and other stress-related functions. Under challenging situations, physiological responses of ABA manifested in the form of morphological, cytological, and anatomical alterations arise as a result of synergistic or antagonistic interaction with multiple phytohormones. This review provides new insight into ABA homeostasis and its perception and signaling crosstalk with other phytohormones at both molecular and physiological level under critical conditions including drought, salinity, heavy metal toxicity, and extreme temperature. The review also reveals the role of ABA in the regulation of various physiological processes via its positive or negative crosstalk with phytohormones, viz., gibberellin, melatonin, cytokinin, auxin, salicylic acid, jasmonic acid, ethylene, brassinosteroids, and strigolactone in response to alteration of environmental conditions. This review forms a basis for designing of plants that will have an enhanced tolerance capability against different abiotic stress.
PMID: 37079058
Plant Cell Rep , IF:4.57 , 2023 May , V42 (5) : P921-937 doi: 10.1007/s00299-023-03001-0
Comparative transcriptome analysis reveals the function of SlPRE2 in multiple phytohormones biosynthesis, signal transduction and stomatal development in tomato.
Institute of Jiangxi Oil-Tea Camellia, Jiujiang University, Jiujiang, 332000, Jiangxi, China. zhuzhiguo@jju.edu.cn.; College of Pharmacy and Life Sciences, Jiujiang University, Jiujiang, 332000, Jiangxi, China. zhuzhiguo@jju.edu.cn.; Institute of Jiangxi Oil-Tea Camellia, Jiujiang University, Jiujiang, 332000, Jiangxi, China.; College of Pharmacy and Life Sciences, Jiujiang University, Jiujiang, 332000, Jiangxi, China.; College of Biological Science and Agriculture, Qiannan Normal University for Nationalities, Duyun, 558000, Guizhou, China.
Transcriptomic, physiological, and qRT-PCR analysis revealed the potential mechanism by which SlPRE2 regulates plant growth and stomatal size via multiple phytohormone pathways in tomato. Paclobutrazol resistance proteins (PREs) are atypical members of the basic/helix-loop-helix (bHLH) transcription factor family that regulate plant morphology, cell size, pigment metabolism and abiotic stress in response to different phytohormones. However, little is known about the network regulatory mechanisms of PREs in plant growth and development in tomato. In this study, the function and mechanism of SlPRE2 in tomato plant growth and development were investigated. The quantitative RT-PCR results showed that the expression of SlPRE2 was regulated by multiple phytohormones and abiotic stresses. It showed light-repressed expression during the photoperiod. The RNA-seq results revealed that SlPRE2 regulated many genes involved in photosynthesis, chlorophyll metabolism, phytohormone metabolism and signaling, and carbohydrate metabolism, suggesting the role of SlPRE2 in gibberellin, brassinosteroid, auxin, cytokinin, abscisic acid and salicylic acid regulated plant development processes. Moreover, SlPRE2 overexpression plants showed widely opened stomata in young leaves, and four genes involved in stomatal development showed altered expression. Overall, the results demonstrated the mechanism by which SlPRE2 regulates phytohormone and stress responses and revealed the function of SlPRE2 in stomatal development in tomato. These findings provide useful clues for understanding the molecular mechanisms of SlPRE2-regulated plant growth and development in tomato.
PMID: 37010556
Plant Cell Rep , IF:4.57 , 2023 May , V42 (5) : P939-952 doi: 10.1007/s00299-023-03002-z
Fusion gene 4CL-CCR promotes lignification in tobacco suspension cells.
State Key Laboratory of Tree Genetics and Breeding, College of Biological Sciences and Technology , Beijing Forestry University, Beijing, 100083, China.; The Tree and Ornamental Plant Breeding and Biotechnology Laboratory of National Forestry and Grassland Administration, Beijing, 100083, China.; State Key Laboratory of Tree Genetics and Breeding, College of Biological Sciences and Technology , Beijing Forestry University, Beijing, 100083, China. gaiying@bjfu.edu.cn.; The Tree and Ornamental Plant Breeding and Biotechnology Laboratory of National Forestry and Grassland Administration, Beijing, 100083, China. gaiying@bjfu.edu.cn.; State Key Laboratory of Tree Genetics and Breeding, College of Biological Sciences and Technology , Beijing Forestry University, Beijing, 100083, China. jiangxn@bjfu.edu.cn.; The Tree and Ornamental Plant Breeding and Biotechnology Laboratory of National Forestry and Grassland Administration, Beijing, 100083, China. jiangxn@bjfu.edu.cn.
The fusion gene 4CL-CCR promotes lignification and activates lignin-related MYB expression in tobacco but inhibits auxin-related gene expression and hinders the auxin absorption of cells. Given the importance of lignin polymers in plant growth and their industrial value, it is necessary to investigate how plants synthesize monolignols and regulate the level of lignin in cell walls. In our previous study, expression of the Populus tomentosa fusion gene 4CL-CCR significantly promoted the production of 4-hydroxycinnamyl alcohols. However, the function of 4CL-CCR in organisms remains poorly understood. In this study, the fusion gene 4CL-CCR was heterologously expressed in tobacco suspension cells. We found that the transgenic suspension cells exhibited lignification earlier. Furthermore, 4CL-CCR significantly reduced the content of phenolic acids and increased the content of aldehydes in the medium, which led to an increase in lignin deposition. Moreover, transcriptome results showed that the genes related to lignin synthesis, such as PAL, 4CL, CCoAOMT and CAD, were significantly upregulated in the 4CL-CCR group. The expression of genes related to auxin, such as ARF3, ARF5 and ARF6, was significantly downregulated. The downregulation of auxin affected the expression of transcription factor MYBs. We hypothesize that the upregulated genes MYB306 and MYB315 are involved in the regulation of cell morphogenesis and lignin biosynthesis and eventually enhance lignification in tobacco suspension cells. Our findings provide insight into the function of 4CL-CCR in lignification and how secondary cell walls are formed in plants.
PMID: 36964306
Plant Cell Rep , IF:4.57 , 2023 Apr , V42 (4) : P749-761 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
Microb Ecol , IF:4.552 , 2023 May , V85 (4) : P1396-1411 doi: 10.1007/s00248-022-01998-7
Microorganisms Associated with the Ambrosial Beetle Xyleborus affinis with Plant Growth-Promotion Activity in Arabidopsis Seedlings and Antifungal Activity Against Phytopathogenic Fungus Fusarium sp. INECOL_BM-06.
Red de Estudios Moleculares Avanzados, Instituto de Ecologia A.C, Xalapa, 91073, Veracruz, Mexico.; Red de Biodiversidad Y Sistematica, Instituto de Ecologia A.C, Carretera Antigua a Coatepec 351, El Haya, 91073, Xalapa, Veracruz, Mexico.; Red de Estudios Moleculares Avanzados, Instituto de Ecologia A.C, Xalapa, 91073, Veracruz, Mexico. randy.ortiz@inecol.mx.; Catedra CONACyT en el Instituto de Ecologia, A.C., Carretera Antigua a Coatepec 351, El Haya, C.P. 91073, Xalapa, Veracruz, Mexico. randy.ortiz@inecol.mx.
Plants interact with a great diversity of microorganisms or insects throughout their life cycle in the environment. Plant and insect interactions are common; besides, a great variety of microorganisms associated with insects can induce pathogenic damage in the host, as mutualist phytopathogenic fungus. However, there are other microorganisms present in the insect-fungal association, whose biological/ecological activities and functions during plant interaction are unknown. In the present work evaluated, the role of microorganisms associated with Xyleborus affinis, an important beetle species within the Xyleborini tribe, is characterized by attacking many plant species, some of which are of agricultural and forestry importance. We isolated six strains of microorganisms associated with X. affinis shown as plant growth-promoting activity and altered the root system architecture independent of auxin-signaling pathway in Arabidopsis seedlings and antifungal activity against the phytopathogenic fungus Fusarium sp. INECOL_BM-06. In addition, evaluating the tripartite interaction plant-microorganism-fungus, interestingly, we found that microorganisms can induce protection against the phytopathogenic fungus Fusarium sp. INECOL_BM-06 involving the jasmonic acid-signaling pathway and independent of salicylic acid-signaling pathway. Our results showed the important role of this microorganisms during the plant- and insect-microorganism interactions, and the biological potential use of these microorganisms as novel agents of biological control in the crops of agricultural and forestry is important.
PMID: 35357520
Physiol Plant , IF:4.5 , 2023 May : Pe13937 doi: 10.1111/ppl.13937
A stratagem for primary root elongation under moderate salt stress in the halophyte Schrenkiella parvula.
Graduate School of Life Sciences, Tohoku University, Sendai, Japan.; Faculty of Science, Department of Biology, Ege University, Bornova, Izmir, Turkey.
Schrenkiella parvula, an Arabidopsis-related halophyte, grows around Lake Tuz (Salt) in Turkey and can survive up to 600 mM NaCl. Here, we performed physiological studies on the roots of S. parvula and A. thaliana seedlings cultivated under a moderate salt condition (100 mM NaCl). Interestingly, S. parvula germinated and grew at 100 mM NaCl, but germination did not occur at salt concentrations above 200 mM. In addition, primary roots elongated much faster at 100 mM NaCl, while being thinner with fewer roots hair, than under NaCl-free conditions. Salt-induced root elongation was due to epidermal cell elongation, but meristem size and meristematic DNA replication were reduced. The expression of genes related to auxin response and biosynthesis was also reduced. Application of exogenous auxin abolished the changes in primary root elongation, suggesting that auxin reduction is the main trigger for root architectural changes in response to moderate salinity in S. parvula. In A. thaliana seeds, germination was maintained up to 200 mM NaCl, but post-germination root elongation was significantly inhibited. Furthermore, primary roots did not promote elongation even under fairly low salt conditions. Compared to A. thaliana, cell death and ROS content in primary roots of salt-stressed plants were significantly lower in S. parvula. These changes in the roots of S. parvula seedlings may be an adaptive strategy to reach lower salinity by advancing into deeper soils, while being impaired by moderate salt stress. This article is protected by copyright. All rights reserved.
PMID: 37243856
Sci Rep , IF:4.379 , 2023 Apr , V13 (1) : P6661 doi: 10.1038/s41598-023-33913-6
Exogenous 24-epibrassinolide ameliorates tolerance to high-temperature by adjusting the biosynthesis of pigments, enzymatic, non-enzymatic antioxidants, and diosgenin content in fenugreek.
Department of Agriculture and Plant Breeding, Faculty of Agriculture, Shahrood University of Technology, Semnan, Iran.; Department of Agriculture and Plant Breeding, Faculty of Agriculture, Shahrood University of Technology, Semnan, Iran. Aminebrahimi@shahroodut.ac.ir.; Plant Breeding and Biotechnology Department, Faculty of Agriculture, Tarbiat Modares University, Tehran, Iran.; Department of Plant Production and Genetics, Faculty of Agriculture, Urmia University, Urmia, Iran. Ha.alipour@urmia.ac.ir.
High-temperature stress is widely considered a main plant-growth-limiting factor. The positive effects of 24-epibrassinolide (EBR) as analogs of brassinosteroids (BRs) in modulating abiotic stresses have led this hormone to be referred to as a growth regulator in plants. The current study highlights the influence of EBR on enhancing tolerance to high-temperature and altering the diosgenin content in fenugreek. Different amounts of EBR (4, 8, and 16 muM), harvesting times (6, and 24 h), as well as temperature regimes (23 degrees C, and 42 degrees C) were, used as treatments. EBR application under normal temperature and high-temperature stress resulted in decreased malondialdehyde content and electrolyte leakage percentage, while the activity of antioxidant enzymes improved significantly. Exogenous EBR application possibly contributes to activating the nitric oxide, H(2)O(2), and ABA-dependent pathways, enhancing the biosynthesis of abscisic acid and auxin, and regulating the signal transduction pathways, which raises fenugreek tolerance to high-temperature. The SQS (eightfold), SEP (2.8-fold), CAS (11-fold), SMT (17-fold), and SQS (sixfold) expression, considerably increased following EBR application (8 muM) compared to the control. Compared to the control, when the short-term (6 h) high-temperature stress was accompanied by EBR (8 muM), a sixfold increase in diosgenin content was achieved. Our findings highlight the potential role of exogenous 24-epibrassinolide in mitigating the high-temperature stress in fenugreek by stimulating the biosynthesis processes of enzymatic and non-enzymatic antioxidants, chlorophylls, and diosgenin. In conclusion, the current results could be of utmost importance in breeding or biotechnology-based programs of fenugreek and also in the researches related to the engineering of the biosynthesis pathway of diosgenin in this valuable plant.
PMID: 37095206
Ann Bot , IF:4.357 , 2023 Apr , V131 (3) : P475-490 doi: 10.1093/aob/mcac161
Specificity in root domain accumulation of Phytoglobin1 and nitric oxide (NO) determines meristematic viability in water-stressed Brassica napus roots.
Department of Plant Science, University of Manitoba, Winnipeg, Manitoba, R3T 2N2, Canada.; Department of Botany, Faculty of Science, Tanta University, Tanta, 31527, Egypt.
BACKGROUND AND AIMS: Drought reduces plant productivity, especially in the susceptible species Brassica napus. Water stress, mimicked by applications of 10 % polyethylene glycol (PEG), elevates nitric oxide (NO) in root cells after a few hours, contributing to degradation of the root apical meristems (RAMs), the function of which relies on auxin and brassinosteroids (BRs). Phytoglobins (Pgbs) are effective NO scavengers induced by this stress. This study examines the effects of BnPgb1 dysregulation in dehydrating B. napus roots, and the spatiotemporal relationship between Pgb1 and activities of auxin and BRs in the regulation of the RAM. METHODS: Brassica napus lines over-expressing [BnPgb1(S)] or down-regulating [BnPgb1(RNAi)] BnPgb1 were exposed to PEG-induced water stress. The localization of BnPgb1, NO, auxin and PIN1 were analysed during the first 48 h, while the expression level of biosynthetic auxin and BR genes was measured during the first 24 h. Pharmacological treatments were conducted to assess the requirement of auxin and BR in dehydrating roots. KEY RESULTS: During PEG stress, BnPgb1 protein accumulated preferentially in the peripheral domains of the root elongation zone, exposing the meristem to NO, which inhibits polar auxin transport (PAT), probably by interfering with PIN1 localization and the synthesis of auxin. Diminished auxin at the root tip depressed the synthesis of BR and caused the degradation of the RAMs. The strength of BnPgb1 signal in the elongation zone was increased in BnPgb1(S) roots, where NO was confined to the most apical cells. Consequently, PAT and auxin synthesis were retained, and the definition of RAMs was maintained. Auxin preservation of the RAM required BRs, although BRs alone was not sufficient to fully rescue drought-damaged RAMs in auxin-depleted environments. CONCLUSIONS: The tissue-specific localization of BnPgb1 and NO determine B. napus root responses to water stress. A model is proposed in which auxin and BRs act as downstream components of BnPgb1 signalling in the preservation of RAMs in dehydrating roots.
PMID: 36571296
Foods , IF:4.35 , 2023 Apr , V12 (8) doi: 10.3390/foods12081648
Transcriptomic Analysis Reveals Genes Associated with the Regulation of Peach Fruit Softening and Senescence during Storage.
Institute of Pomology, Jiangsu Academy of Agricultural Sciences/Jiangsu Key Laboratory for Horticultural Crop Genetic Improvement, Nanjing 210014, China.; College of Horticulture, Nanjing Agricultural University, Nanjing 210095, China.
Peach (Prunus persica (L.) Batsch) is a highly desirable fruit that is consumed around the world. However, the peach fruit is highly perishable after harvest, a characteristic that limits the distribution and supply to the market and causes heavy economic losses. Thus, peach fruit softening and senescence after harvest urgently need to be addressed. In the current study, transcriptomic analysis was performed to identify candidate genes associated with peach fruit softening and senescence, comparing peach fruit from cultivars with different flesh textures, namely melting and stony hard (SH) flesh textures during storage at room temperature. The mitogen-activated protein kinase signaling pathway-plant and plant hormone signal transduction pathways were associated with peach fruit softening and senescence according to the Venn diagram analysis and weighted gene co-expression network analysis. The expression levels of seven genes, including Prupe.1G034300, Prupe.2G176900, Prupe.3G024700, Prupe.3G098100, Prupe.6G226100, Prupe.7G234800, and Prupe.7G247500, were higher in melting peach fruit than in SH peach fruit during storage. Furthermore, the SH peach fruit softened rapidly after 1-naphthylacetic acid treatment, during which the levels of expression of these seven genes, determined by a quantitative reverse transcription polymerase chain reaction, were strongly induced and upregulated. Thus, these seven genes may play essential roles in regulating peach fruit softening and senescence.
PMID: 37107443
Plant Physiol Biochem , IF:4.27 , 2023 May , V198 : P107683 doi: 10.1016/j.plaphy.2023.107683
Cytokinins act synergistically with heat acclimation to enhance rice thermotolerance affecting hormonal dynamics, gene expression and volatile emission.
Laboratory of Hormonal Regulations in Plants, Institute of Experimental Botany, Czech Academy of Sciences, Rozvojova 263, 165 02, Prague, Czech Republic. Electronic address: prerostova@ueb.cas.cz.; Laboratory of Plant Biotechnologies, Institute of Experimental Botany, Czech Academy of Sciences, Rozvojova 313, 165 02, Prague, Czech Republic. Electronic address: rezek@ueb.cas.cz.; Laboratory of Hormonal Regulations in Plants, Institute of Experimental Botany, Czech Academy of Sciences, Rozvojova 263, 165 02, Prague, Czech Republic. Electronic address: jarosova@ueb.cas.cz.; Laboratory of Hormonal Regulations in Plants, Institute of Experimental Botany, Czech Academy of Sciences, Rozvojova 263, 165 02, Prague, Czech Republic. Electronic address: lacek@ueb.cas.cz.; Laboratory of Hormonal Regulations in Plants, Institute of Experimental Botany, Czech Academy of Sciences, Rozvojova 263, 165 02, Prague, Czech Republic. Electronic address: dobrev@ueb.cas.cz.; Laboratory of Plant Biotechnologies, Institute of Experimental Botany, Czech Academy of Sciences, Rozvojova 313, 165 02, Prague, Czech Republic. Electronic address: marsik@ueb.cas.cz.; Laboratory of Hormonal Regulations in Plants, Institute of Experimental Botany, Czech Academy of Sciences, Rozvojova 263, 165 02, Prague, Czech Republic. Electronic address: gaudinova@ueb.cas.cz.; Laboratory of Hormonal Regulations in Plants, Institute of Experimental Botany, Czech Academy of Sciences, Rozvojova 263, 165 02, Prague, Czech Republic. Electronic address: knirsch@ueb.cas.cz.; Laboratory of Growth Regulators, Institute of Experimental Botany, Czech Academy of Sciences, Slechtitelu 27, 783 71, Olomouc, Czech Republic; Department of Chemical Biology, Faculty of Science, Palacky University, 17. listopadu 1192/12, 779 00, Olomouc, Czech Republic. Electronic address: karel.dolezal@upol.cz.; Laboratory of Growth Regulators, Institute of Experimental Botany, Czech Academy of Sciences, Slechtitelu 27, 783 71, Olomouc, Czech Republic; Department of Chemical Biology, Faculty of Science, Palacky University, 17. listopadu 1192/12, 779 00, Olomouc, Czech Republic. Electronic address: lucie.plihalova@upol.cz.; Laboratory of Plant Biotechnologies, Institute of Experimental Botany, Czech Academy of Sciences, Rozvojova 313, 165 02, Prague, Czech Republic. Electronic address: vanek@ueb.cas.cz.; Department of Biology, University of North Carolina, Chapel Hill, NC, 27599, USA. Electronic address: jkieber@bio.unc.edu.; Laboratory of Hormonal Regulations in Plants, Institute of Experimental Botany, Czech Academy of Sciences, Rozvojova 263, 165 02, Prague, Czech Republic. Electronic address: vankova@ueb.cas.cz.
Heat stress is a frequent environmental constraint. Phytohormones can significantly affect plant thermotolerance. This study compares the effects of exogenous cytokinin meta-topolin-9-(tetrahydropyran-2-yl)purine (mT9THP) on rice (Oryza sativa) under control conditions, after acclimation by moderate temperature (A; 37 degrees C, 2h), heat stress (HS; 45 degrees C, 6h) and their combination (AHS). mT9THP is a stable cytokinin derivative that releases active meta-topolin gradually, preventing the rapid deactivation reported after exogenous cytokinin application. Under control conditions, mT9THP negatively affected jasmonic acid in leaves and abscisic and salicylic acids in crowns (meristematic tissue crucial for tillering). Exogenous cytokinin stimulated the emission of volatile organic compounds (VOC), especially 2,3-butanediol. Acclimation upregulated trans-zeatin, expression of stress- and hormone-related genes, and VOC emission. The combination of acclimation and mT9THP promoted the expression of stress markers and antioxidant enzymes and moderately increased VOC emission, including 2-ethylhexyl salicylate or furanones. AHS and HS responses shared some common features, namely, increase of ethylene precursor aminocyclopropane-1-carboxylic acid (ACC), cis-zeatin and cytokinin methylthio derivatives, as well as the expression of heat shock proteins, alternative oxidases, and superoxide dismutases. AHS specifically induced jasmonic acid and auxin indole-3-acetic acid levels, diacylglycerolipids with fewer double bonds, and VOC emissions [e.g., acetamide, lipoxygenase (LOX)-derived volatiles]. Under direct HS, exogenous cytokinin mimicked some positive acclimation effects. The combination of mT9THP and AHS had the strongest thermo-protective effect, including a strong stimulation of VOC emissions (including LOX-derived ones). These results demonstrate for the first time the crucial contribution of volatiles to the beneficial effects of cytokinin and AHS on rice thermotolerance.
PMID: 37062127
Environ Sci Pollut Res Int , IF:4.223 , 2023 Apr , V30 (17) : P49290-49300 doi: 10.1007/s11356-023-25777-0
Nicosulfuron stress on the glyoxalase system and endogenous hormone content in sweet maize seedlings.
Institute of Maize and Featured Upland Crops, Zhejiang Academy of Agricultural Sciences, Dongyang, 322100, China.; College of Agronomy and Biotechnology, Hebei Key Laboratory of Crop Stress Biology, Hebei Normal University of Science &Technology, Qinhuangdao, 066000, China.; Shanghai Engineering Research Center of Specialty Maize, Shanghai Academy of Agricultural Sciences, Shanghai, 201106, China.; Institute of Maize and Featured Upland Crops, Zhejiang Academy of Agricultural Sciences, Dongyang, 322100, China. lvgh@zaas.ac.cn.
To reduce the harmful effects of nicosulfuron on sweet corn, the physiological regulation mechanism of sweet corn detoxification was studied. This study analyzed the effects of nicosulfuron stress on the glyoxalase system, hormone content, and key gene expression of nicosulfuron-tolerant "HK301" and nicosulfuron-sensitive "HK320" sweet corn seedling sister lines. After spraying nicosulfuron, the methylglyoxal (MG) content in HK301 increased first and then decreased. Glyoxalase I (GlyI) and glyoxalase II (GlyII) activities, non-enzymatic glutathione (GSH), and the glutathione redox state glutathione/(glutathione + glutathione disulfide) (GSH/(GSH + GSSG)) showed a similar trend as the MG content. Abscisic acid (ABA), gibberellin (GA), and zeatin nucleoside (ZR) also increased first and then decreased, whereas the auxin (IAA) increased continuously. In HK301, all indices after spraying nicosulfuron were significantly greater than those of the control. In HK320, MG accumulation continued to increase after nicosulfuron spraying and GlyI and GlyII activities, and GSH first increased and then decreased after 1 day of stress. The indicators above were significantly greater than the control. The GSH/(GSH + GSSG) ratio showed a decreasing trend and was significantly smaller than the control. Furthermore, ABA and IAA continued to increase, and the GA and ZR first increased and then decreased. Compared with HK320, HK301 significantly upregulated the transcription levels of GlyI and GlyII genes in roots, stems, and leaves. Comprehensive analysis showed that sweet maize seedlings improved their herbicide resistance by changing the glyoxalase system and regulating endogenous hormones. The results provide a theoretical basis for further understanding the response mechanism of the glyoxalase system and the regulation characteristics of endogenous hormones in maize under nicosulfuron stress.
PMID: 36773263
BMC Plant Biol , IF:4.215 , 2023 May , V23 (1) : P265 doi: 10.1186/s12870-023-04253-4
Different evolutionary patterns of TIR1/AFBs and AUX/IAAs and their implications for the morphogenesis of land plants.
State Key Laboratory of Crop Genetics and Germplasm Enhancement, College of Horticulture, Nanjing Agricultural University, Nanjing, 210095, China.; State Key Laboratory of Crop Genetics and Germplasm Enhancement, College of Horticulture, Nanjing Agricultural University, Nanjing, 210095, China. zcheng@utk.edu.
BACKGROUND: The plant hormone auxin is widely involved in plant growth, development, and morphogenesis, and the TIR1/AFB and AUX/IAA proteins are closely linked to rapid auxin response and signal transmission. However, their evolutionary history, historical patterns of expansion and contraction, and changes in interaction relationships are still unknown. RESULTS: Here, we analyzed the gene duplications, interactions, and expression patterns of TIR1/AFBs and AUX/IAAs to understand their underlying mechanisms of evolution. The ratios of TIR1/AFBs to AUX/IAAs range from 4:2 in Physcomitrium patens to 6:29 in Arabidopsis thaliana and 3:16 in Fragaria vesca. Whole-genome duplication (WGD) and tandem duplication have contributed to the expansion of the AUX/IAA gene family, but numerous TIR1/AFB gene duplicates were lost after WGD. We further analyzed the expression profiles of TIR1/AFBs and AUX/IAAs in different tissue parts of Physcomitrium patens, Selaginella moellendorffii, Arabidopsis thaliana and Fragaria vesca, and found that TIR1/AFBs and AUX/IAAs were highly expressed in all tissues in P. patens, S. moellendorffii. In A. thaliana and F. vesca, TIR1/AFBs maintained the same expression pattern as the ancient plants with high expression in all tissue parts, while AUX/IAAs appeared tissue-specific expression. In F. vesca, 11 AUX/IAAs interacted with TIR1/AFBs with different interaction strengths, and the functional specificity of AUX/IAAs was related to their ability to bind TIR1/AFBs, thus promoting the development of specific higher plant organs. Verification of the interactions among TIR1/AFBs and AUX/IAAs in Marchantia polymorpha and F. vesca also showed that the regulation of AUX/IAA members by TIR1/AFBs became more refined over the course of plant evolution. CONCLUSIONS: Our results indicate that specific interactions and specific gene expression patterns both contributed to the functional diversification of TIR1/AFBs and AUX/IAAs.
PMID: 37202746
BMC Plant Biol , IF:4.215 , 2023 Apr , V23 (1) : P176 doi: 10.1186/s12870-023-04168-0
Uncovering early transcriptional regulation during adventitious root formation in Medicago sativa.
School of Grassland Science, Beijing Forestry University, Beijing, 100083, China.; College of Life Sciences, University of Chinese Academy of Sciences, Beijing, 100049, China.; Beijing Tide Pharmaceutical Co., Ltd, Beijing, 100176, China.; The UWA Institute of Agriculture, and UWA School of Agriculture and Environment, The University of Western Australia, Perth, WA, 6001, Australia.; School of Grassland Science, Beijing Forestry University, Beijing, 100083, China. chaoyuehui@bjfu.edu.cn.; College of Grassland, Resources and Environment, Inner Mongolia Agricultural University, Key Laboratory of Grassland Resources (IMAU), Ministry of Education, Hohhot, 010021, China. zhaoyannmg@163.com.
BACKGROUND: Alfalfa (Medicago sativa L.) as an important legume plant can quickly produce adventitious roots (ARs) to form new plants by cutting. But the regulatory mechanism of AR formation in alfalfa remains unclear. RESULTS: To better understand the rooting process of alfalfa cuttings, plant materials from four stages, including initial separation stage (C stage), induction stage (Y stage), AR primordium formation stage (P stage) and AR maturation stage (S stage) were collected and used for RNA-Seq. Meanwhile, three candidate genes (SAUR, VAN3 and EGLC) were selected to explore their roles in AR formation. The numbers of differentially expressed genes (DEGs) of Y-vs-C (9,724) and P-vs-Y groups (6,836) were larger than that of S-vs-P group (150), indicating highly active in the early AR formation during the complicated development process. Pathways related to cell wall and sugar metabolism, root development, cell cycle, stem cell, and protease were identified, indicating that these genes were involved in AR production. A large number of hormone-related genes associated with the formation of alfalfa ARs have also been identified, in which auxin, ABA and brassinosteroids are thought to play key regulatory roles. Comparing with TF database, it was found that AP2/ERF-ERF, bHLH, WRKY, NAC, MYB, C2H2, bZIP, GRAS played a major regulatory role in the production of ARs of alfalfa. Furthermore, three identified genes showed significant promotion effect on AR formation. CONCLUSIONS: Stimulation of stem basal cells in alfalfa by cutting induced AR production through the regulation of various hormones, transcription factors and kinases. This study provides new insights of AR formation in alfalfa and enriches gene resources in crop planting and cultivation.
PMID: 37016323
Tree Physiol , IF:4.196 , 2023 May doi: 10.1093/treephys/tpad060
Comparative transcriptomics provides insights into the pathogenic immune response of brown leaf spots in weeping forsythia.
School of Pharmacy, Henan University, Kaifeng, Henan 475004, China.; Henan Province Engineering Research Center of High Value Utilization to Natural Medical Resource in Yellow River Basin, Kaifeng 475004, China.; School of Life Sciences, Henan University, Kaifeng, Henan 475004, China.; College of Life Science and Technology, Inner Mongolia Normal University, Huhehaote, China.; State Key Laboratory of Tree Genetics and Breeding, Chinese Academy of Forestry, Beijing, China.
Weeping forsythia is an important ornamental, ecological, and medicinal plant. Brown leaf spots reduce the large-scale production of weeping forsythia as a medicinal crop. Alternaria alternata is a pathogen causing brown leaf spots in weeping forsythia; however, its pathogenesis and the immune response mechanisms of weeping forsythia remain unclear. In this study, we identified the two mechanisms based on morphological anatomy, physiological indexes, and gene expression analyses. Our results showed that A. alternata induced leaf stomata to open, invaded the mesophyll, dissolved the cell wall, destroyed the cell membrane, and decreased the number of chloroplasts by up-regulating the expression of auxin-activated signaling pathway genes. A. alternata also down-regulated iron ion homeostasis and binding-related genes, which caused an increase in the levels of iron ions and reactive oxygen species in leaves. These processes eventually led to programmed cell death, destroying palisade and spongy tissues and causing the formation of iron rust spots. A. alternata also caused defense and hypersensitive responses in weeping forsythia through signaling pathways mediated by flg22-like and elf18-like polypeptides, ethylene, H2O2, and bacterial secretion systems. Our study provides a theoretical basis for the control of brown leaf spots in weeping forsythia.
PMID: 37171622
Tree Physiol , IF:4.196 , 2023 May , V43 (5) : P851-866 doi: 10.1093/treephys/tpac149
Physiological and transcriptome analyses of the effects of excessive water deficit on malic acid accumulation in apple.
College of Horticulture, Gansu Agricultural University, Lanzhou 730070, China.
Acidity is a determinant of the organoleptic quality of apple, whereas its regulatory mechanism under water stress remains obscure. Fruit from apple 'Yanfu 3' of Fuji trees grown under normal water irrigation (CK), excessive water deficit treatment (DRT) and excessive water irrigation treatment (WAT) were sampled at 85, 100, 115, 130, 145, 160 and 175 days after full bloom designated stages S1, S2, S3, S4, S5, S6 and S7, respectively. DRT treatment reduced the individual fruit weight and fruit moisture content, and increased fruit firmness. The malate content of DRT treatment was higher than that of CK and WAT from stages S1 to S7. RNA sequencing (RNA-seq) analysis of the transcriptome at stages S4, S6 and S7 indicated that malate anabolism was associated with cysteine and methionine, auxin signaling, glyoxylate and dicarboxylate and pyruvate metabolism. Overexpression of MdPEPC4 increased the malate content in apple calli induced by 4% PEG. Our study provides novel insights into the effects of water stress on the molecular mechanism underlying apple fruit acidity.
PMID: 36579825
Planta , IF:4.116 , 2023 May , V257 (6) : P120 doi: 10.1007/s00425-023-04144-w
The inhibition of maize (Zea mays L.) root stem cell regeneration by low oxygen is attenuated by Phytoglobin 1 (Pgb1) through changes in auxin and jasmonic acid.
Department of Plant Science, University of Manitoba, Winnipeg, MB, R3T 2N2, Canada.; Department of Botany, Faculty of Science, Tanta University, Tanta, 31527, Egypt.; Department of Plant Science, University of Manitoba, Winnipeg, MB, R3T 2N2, Canada. stasolla@ms.umanitoba.ca.
Over-expression of Phytoglobin1 increases the viability of maize root stem cells to low oxygen stress through changes in auxin and jasmonic acid responses. Hypoxia inhibits maize (Zea mays L.) root growth by deteriorating the quiescent center (QC) stem cells of the root apical meristem. Over-expression of the Phytoglobin1 ZmPgb1.1 alleviates these effects through the retention of the auxin flow along the root profile required for the specification of the QC stem cells. To identify QC-specific hypoxia responses and determine whether ZmPgb1.1 exercises a direct role on QC stem cells, we performed a QC functionality test. This was done by estimating the ability of QCs to regenerate a root in vitro in a hypoxic environment. Hypoxia decreased the functionality of the QCs by depressing the expression of several genes participating in the synthesis and response of auxin. This was accompanied by a decrease in DR5 signal, a suppression of PLETHORA and WOX5, two markers of QC cell identity, and a reduction in expression of genes participating in JA synthesis and signaling. Over-expression of ZmPgb1.1 was sufficient to mitigate all these responses. Through pharmacological alterations of auxin and JA, it is demonstrated that both hormones are required for QC functionality under hypoxia, and that JA acts downstream of auxin during QC regeneration. A model is proposed whereby the ZmPgb1.1 maintenance of auxin synthesis in hypoxic QCs is determinant for the retention of their functionality, with JA supporting the regeneration of roots from the QCs.
PMID: 37178357
Planta , IF:4.116 , 2023 May , V257 (6) : P108 doi: 10.1007/s00425-023-04136-w
Advances in the study of the function and mechanism of the action of flavonoids in plants under environmental stresses.
School of Environmental Science, Liaoning University, Shenyang, 110036, China. wujieting@lnu.edu.cn.; School of Environmental Science, Liaoning University, Shenyang, 110036, China.; State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin, 150090, China.; Kerchin District Branch Office, Tongliao City Ecological Environment Bureau, Tongliao, 028006, China.; Dalian Neusoft University of Information, Dalian, 116032, China.
This review summarizes the anti-stress effects of flavonoids in plants and highlights its role in the regulation of polar auxin transport and free radical scavenging mechanism. As secondary metabolites widely present in plants, flavonoids play a vital function in plant growth, but also in resistance to stresses. This review introduces the classification, structure and synthetic pathways of flavonoids. The effects of flavonoids in plant stress resistance were enumerated, and the mechanism of flavonoids in plant stress resistance was discussed in detail. It is clarified that plants under stress accumulate flavonoids by regulating the expression of flavonoid synthase genes. It was also determined that the synthesized flavonoids are transported in plants through three pathways: membrane transport proteins, vesicles, and bound to glutathione S-transferase (GST). At the same time, the paper explores that flavonoids regulate polar auxin transport (PAT) by acting on the auxin export carrier PIN-FORMED (PIN) in the form of ATP-binding cassette subfamily B/P-glycoprotein (ABCB/PGP) transporter, which can help plants to respond in a more dominant form to stress. We have demonstrated that the number and location of hydroxyl groups in the structure of flavonoids can determine their free radical scavenging ability and also elucidated the mechanism by which flavonoids exert free radical removal in cells. We also identified flavonoids as signaling molecules to promote rhizobial nodulation and colonization of arbuscular mycorrhizal fungi (AMF) to enhance plant-microbial symbiosis in defense to stresses. Given all this knowledge, we can foresee that the in-depth study of flavonoids will be an essential way to reveal plant tolerance and enhance plant stress resistance.
PMID: 37133783
Planta , IF:4.116 , 2023 Apr , V257 (5) : P94 doi: 10.1007/s00425-023-04126-y
Novel insights into maize (Zea mays) development and organogenesis for agricultural optimization.
Crop Genesis and Novel Agronomy Center, Yangling, 712100, Shaanxi, China. zhiyinzl@163.com.; Shandong ZhongnongTiantai Seed Co., Ltd, Pingyi, 273300, Shandong, China.; State Key Laboratory of Crop Biology, Shandong Agricultural University, Tai'an, 271018, Shandong, China. clwu@sdau.edu.cn.; College of Agronomy, Shandong Agricultural University, Tai'an, 271018, Shandong, China. clwu@sdau.edu.cn.
In maize, intrinsic hormone activities and sap fluxes facilitate organogenesis patterning and plant holistic development; these hormone movements should be a primary focus of developmental biology and agricultural optimization strategies. Maize (Zea mays) is an important crop plant with distinctive life history characteristics and structural features. Genetic studies have extended our knowledge of maize developmental processes, genetics, and molecular ecophysiology. In this review, the classical life cycle and life history strategies of maize are analyzed to identify spatiotemporal organogenesis properties and develop a definitive understanding of maize development. The actions of genes and hormones involved in maize organogenesis and sex determination, along with potential molecular mechanisms, are investigated, with findings suggesting central roles of auxin and cytokinins in regulating maize holistic development. Furthermore, investigation of morphological and structural characteristics of maize, particularly node ubiquity and the alternate attachment pattern of lateral organs, yields a novel regulatory model suggesting that maize organ initiation and subsequent development are derived from the stimulation and interaction of auxin and cytokinin fluxes. Propositions that hormone activities and sap flow pathways control organogenesis are thoroughly explored, and initiation and development processes of distinctive maize organs are discussed. Analysis of physiological factors driving hormone and sap movement implicates cues of whole-plant activity for hormone and sap fluxes to stimulate maize inflorescence initiation and organ identity determination. The physiological origins and biogenetic mechanisms underlying maize floral sex determination occurring at the tassel and ear spikelet are thoroughly investigated. The comprehensive outline of maize development and morphogenetic physiology developed in this review will enable farmers to optimize field management and will provide a reference for de novo crop domestication and germplasm improvement using genome editing biotechnologies, promoting agricultural optimization.
PMID: 37031436
Membranes (Basel) , IF:4.106 , 2023 Apr , V13 (4) doi: 10.3390/membranes13040406
Multifractal Analysis of the Influence of Indole-3-Acetic Acid on Fast-Activating Vacuolar (FV) Channels of Beta vulgaris L. Taproot Cells.
Institute of Theoretical Physics, University of Wroclaw, 50-204 Wroclaw, Poland.; Physics and Biophysics Department, Wroclaw University of Environmental and Life Sciences, 50-375 Wroclaw, Poland.; Faculty of Natural Sciences, Institute of Biology, Biotechnology and Environmental Protection, University of Silesia in Katowice, 40-032 Katowice, Poland.
In this paper, the multifractal properties of the ion current time series in the fast-activating vacuolar (FV) channels of Beta vulgaris L. taproot cells were investigated. These channels are permeable for only monovalent cations and mediate K(+) at very low concentrations of cytosolic Ca(2+) and large voltages of either polarity. Using the patch clamp technique, the currents of the FV channels in red beet taproot vacuoles were recorded and analysed by using the multifractal detrended fluctuation analysis (MFDFA) method. The activity of the FV channels depended on the external potential and was sensitive to the auxin. It was also shown that the singularity spectrum of the ion current in the FV channels is non-singular, and the multifractal parameters, i.e., the generalised Hurst exponent and the singularity spectrum, were modified in the presence of IAA. Taking into account the obtained results, it can be suggested that the multifractal properties of fast-activating vacuolar (FV) K(+) channels, indicating the existence of long-term memory, should be taken into account in the molecular mechanism of the auxin-induced growth of plant cells.
PMID: 37103833
Plant Genome , IF:4.089 , 2023 May : Pe20343 doi: 10.1002/tpg2.20343
Proteomic analysis of near-isogenic lines reveals key biomarkers on wheat chromosome 4B conferring drought tolerance.
UWA School of Agriculture and Environment, The University of Western Australia, Crawley, Western Australia, Australia.; The UWA Institute of Agriculture, The University of Western Australia, Crawley, Western Australia, Australia.; Department of Primary Industries and Regional Development, South Perth, Western Australia, Australia.; Proteomics International, Crawley, Western Australia, Australia.; Harry Perkins Institute of Medical Research, QEII Medical Centre, The University of Western Australia, Crawley, Western Australia, Australia.
Drought is a major constraint for wheat production that is receiving increased attention due to global climate change. This study conducted isobaric tags for relative and absolute quantitation proteomic analysis on near-isogenic lines to shed light on the underlying mechanism of qDSI.4B.1 quantitative trait loci (QTL) on the short arm of chromosome 4B conferring drought tolerance in wheat. Comparing tolerant with susceptible isolines, 41 differentially expressed proteins were identified to be responsible for drought tolerance with a p-value of < 0.05 and fold change >1.3 or <0.7. These proteins were mainly enriched in hydrogen peroxide metabolic activity, reactive oxygen species metabolic activity, photosynthetic activity, intracellular protein transport, cellular macromolecule localization, and response to oxidative stress. Prediction of protein interactions and pathways analysis revealed the interaction between transcription, translation, protein export, photosynthesis, and carbohydrate metabolism as the most important pathways responsible for drought tolerance. The five proteins, including 30S ribosomal protein S15, SRP54 domain-containing protein, auxin-repressed protein, serine hydroxymethyltransferase, and an uncharacterized protein with encoding genes on 4BS, were suggested as candidate proteins responsible for drought tolerance in qDSI.4B.1 QTL. The gene coding SRP54 protein was also one of the differentially expressed genes in our previous transcriptomic study.
PMID: 37199103
Plant Mol Biol , IF:4.076 , 2023 May doi: 10.1007/s11103-023-01355-3
Ectopic overexpression of TaHsfA5 promotes thermomorphogenesis in Arabidopsis thaliana and thermotolerance in Oryza sativa.
Department of Plant Molecular Biology, University of Delhi South Campus, Benito Juarez Road, New Delhi, 110021, India.; Department of Plant Molecular Biology, University of Delhi South Campus, Benito Juarez Road, New Delhi, 110021, India. param@genomeindia.org.
Heat stress transcription factors (Hsfs) play an important role in regulating the heat stress response in plants. Among the Hsf family members, the group A members act upstream in initiating the response upon sensing heat stress and thus, impart thermotolerance to the plants. In the present study, wheat HsfA5 (TaHsfA5) was found to be one of the Hsfs, which was upregulated both in heat stress and during the recovery period after the stress. TaHsfA5 was found to interact with TaHsfA3 and TaHsfA4, both of which are known to positively regulate the heat stress-responsive genes. Apart from these, TaHsfA5 also interacted with TaHSBP2 protein, whose role has been implicated in attenuating the heat stress response. Further, its heterologous overexpression in Arabidopsis and Oryza sativa promoted thermotolerance in these plants. This indicated that TaHsfA5 positively regulated the heat stress response. Interestingly, the TaHsfA5 overexpression Arabidopsis plants when grown at warm temperatures showed a hyper-thermomorphogenic response in comparison to the wild-type plants. This was found to be consistent with the higher expression of PIF4 and its target auxin-responsive genes in these transgenics in contrast to the wild-type plants. Thus, these results suggest the involvement of TaHsfA5 both in the heat stress response as well as in the thermomorphogenic response in plants.
PMID: 37166615
Plant Mol Biol , IF:4.076 , 2023 May , V112 (1-2) : P85-98 doi: 10.1007/s11103-023-01354-4
Identification and transcriptome data analysis of ARF family genes in five Orchidaceae species.
International Center for Bamboo and Rattan, Chaoyang District, Beijing, China.; Key Laboratory of National Forestry and Grassland Administration/Beijing for Bamboo & Rattan Science and Technology, Chaoyang District, Beijing, China.; Pingxiang Bamboo Forest Ecosystem Research Station, Pingxiang, Guangxi, China.; International Center for Bamboo and Rattan, Chaoyang District, Beijing, China. hutao@icbr.ac.cn.; Key Laboratory of National Forestry and Grassland Administration/Beijing for Bamboo & Rattan Science and Technology, Chaoyang District, Beijing, China. hutao@icbr.ac.cn.; Pingxiang Bamboo Forest Ecosystem Research Station, Pingxiang, Guangxi, China. hutao@icbr.ac.cn.
The Orchidaceae is a large family of perennial herbs especially noted for the exceptional diversity of specialized flowers. Elucidating the genetic regulation of flowering and seed development of orchids is an important research goal with potential utility in orchid breeding programs. Auxin Response Factor (ARF) genes encode auxin-responsive transcription factors, which are involved in the regulation of diverse morphogenetic processes, including flowering and seed development. However, limited information on the ARF gene family in the Orchidaceae is available. In this study, 112 ARF genes were identified in the genomes of 5 orchid species (Apostasia shenzhenica, Dendrobium catenatum, Phalaenopsis aphrodite, Phalaenopsis equestris and Vanilla planifolia,). These genes were grouped into 7 subfamilies based on their phylogenetic relationships. Compared with the ARF family in model plants, such as Arabidopsis thaliana and Oryza sativa, one group of ARF genes involved in pollen wall synthesis has been lost during evolution of the Orchidaceae. This loss corresponds with absence of the exine in the pollinia. Through mining of the published genomic and transcriptomic data for the 5 orchid species: the ARF genes of subfamily 4 may play an important role in flower formation and plant growth, whereas those of subfamily 3 are potentially involved in pollen wall development. the study results provide novel insights into the genetic regulation of unique morphogenetic phenomena of orchids, which lay a foundation for further analysis of the regulatory mechanisms and functions of sexual reproduction-related genes in orchids.
PMID: 37103774
Plant Mol Biol , IF:4.076 , 2023 May , V112 (1-2) : P1-18 doi: 10.1007/s11103-023-01341-9
Coordination of floral and fiber development in cotton (Gossypium) by hormone- and flavonoid-signalling associated regulatory miRNAs.
School of Biotechnology, Gautam Buddha University, Greater Noida, 201312, India.; Center for Genetic Manipulation of Crop Plants, University of Delhi South Campus, New Delhi, 110021, India.; School of Biotechnology, Gautam Buddha University, Greater Noida, 201312, India. bhupendra@gbu.ac.in.
Various plant development activities and stress responses are tightly regulated by various microRNAs (miRNA) and their target genes, or transcription factors in a spatiotemporal manner. Here, to exemplify how flowering-associated regulatory miRNAs synchronize their expression dynamics during floral and fiber development in cotton, constitutive expression diminution transgenic lines of auxin-signaling regulatory Gh-miR167 (35S-MIM167) were developed through target mimicry approach. 'Moderate' (58% to 80%)- and 'high' (> 80%)-Gh-miR167 diminution mimic lines showed dosage-dependent developmental deformities in anther development, pollen maturation, and fruit (= boll) formation. Cross pollination of 'moderate' 35S-MIM167 mimic lines with wild type (WT) plant partially restored boll formation and emergence of fiber initials on the ovule surface. Gh-miR167 diminution favored organ-specific transcription biases in miR159, miR166 as well as miR160, miR164, and miR172 along with their target genes during anther and petal development, respectively. Similarly, accumulative effect of percent Gh-miR167 diminution, cross regulation of its target ARF6/8 genes, and temporal mis-expression of hormone signaling- and flavonoid biosynthesis-associated regulatory miRNAs at early fiber initiation stage caused irregular fiber formation. Spatial and temporal transcription proportions of regulatory miRNAs were also found crucial for the execution of hormone- and flavonoid-dependent progression of floral and fiber development. These observations discover how assorted regulatory genetic circuits get organized in response to Gh-miR167 diminution and converge upon ensuing episodes of floral and fiber development in cotton.
PMID: 37067671
BMC Genomics , IF:3.969 , 2023 Apr , V24 (1) : P199 doi: 10.1186/s12864-023-09263-y
Genome-wide identification of Aux/IAA and ARF gene families reveal their potential roles in flower opening of Dendrobium officinale.
Key Laboratory of South China Agricultural Plant Molecular Analysis and Genetic Improvement & Guangdong Provincial Key Laboratory of Applied Botany, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou, 510650, China.; South China National Botanical Garden, Guangzhou, 510650, China.; University of the Chinese Academy of Sciences, Beijing, 100049, China.; , Miki-Cho, Kagawa-Ken, Japan.; Rice Research Institute, Guangdong Academy of Agricultural Sciences & Guangdong Key Laboratory of New Technology in Rice Breeding & Guangdong Rice Engineering Laboratory, Guangzhou, 510640, China. baisong@gdaas.cn.; Key Laboratory of South China Agricultural Plant Molecular Analysis and Genetic Improvement & Guangdong Provincial Key Laboratory of Applied Botany, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou, 510650, China. hechunmei2012@scbg.ac.cn.; South China National Botanical Garden, Guangzhou, 510650, China. hechunmei2012@scbg.ac.cn.
BACKGROUND: The auxin indole-3-acetic acid (IAA) is a vital phytohormone that influences plant growth and development. Our previous work showed that IAA content decreased during flower development in the medicinally important orchid Dendrobium officinale, while Aux/IAA genes were downregulated. However, little information about auxin-responsive genes and their roles in D. officinale flower development exists. RESULTS: This study validated 14 DoIAA and 26 DoARF early auxin-responsive genes in the D. officinale genome. A phylogenetic analysis classified the DoIAA genes into two subgroups. An analysis of cis-regulatory elements indicated that they were related by phytohormones and abiotic stresses. Gene expression profiles were tissue-specific. Most DoIAA genes (except for DoIAA7) were sensitive to IAA (10 mumol/L) and were downregulated during flower development. Four DoIAA proteins (DoIAA1, DoIAA6, DoIAA10 and DoIAA13) were mainly localized in the nucleus. A yeast two-hybrid assay showed that these four DoIAA proteins interacted with three DoARF proteins (DoARF2, DoARF17, DoARF23). CONCLUSIONS: The structure and molecular functions of early auxin-responsive genes in D. officinale were investigated. The DoIAA-DoARF interaction may play an important role in flower development via the auxin signaling pathway.
PMID: 37055721
Pestic Biochem Physiol , IF:3.963 , 2023 Jun , V193 : P105450 doi: 10.1016/j.pestbp.2023.105450
Multiple resistance of Echinochloa phyllopogon to synthetic auxin, ALS-, and ACCase-inhibiting herbicides in Northeast China.
Shenyang Agricultural University, College of Plant Protection, Shenyang, Liaoning 110866, China.; Agricultural and Rural Bureau of Caofeidian District, Tangshan, Hebei 063299, China.; Shenyang Agricultural University, College of Plant Protection, Shenyang, Liaoning 110866, China. Electronic address: jimingshan@163.com.
Echinochloa phyllopogon is a self-pollinating allotetraploid weed and a serious threat to global rice production. One sensitive and three multiple-resistant populations collected from two provinces of Northeast China were used to analyze the mechanism of multiple resistance of E. phyllopogon to penoxsulam, metamifop, and quinclorac. Compared with the sensitive population LN12, LN1 showed higher resistance to these three herbicides; LN24 showed medium resistance to penoxsulam and metamifop and higher resistance to quinclorac (274-fold); HLJ4 showed low resistance to penoxsulam and high resistance to metamifop and quinclorac. Target sequence analysis showed no mutations in acetolactate synthase or acetyl-CoA carboxylase genes. In-vitro enzyme activity analysis showed that the activity of the target enzyme of multiple herbicide-resistant populations was similar to that of the sensitive population. The P450 inhibitor, malathion, noticeably increased the sensitivity of LN1, LN24, and HLJ4 to penoxsulam, LN1 to metamifop, and HLJ4 to quinclorac. Under all four treatments, the GSTs activities of resistant and sensitive populations showed an increasing trend from day 1 to day 5, but the sensitivity and activity of GSTs were higher in the multiple-resistant population than that in the sensitive population LN12. This study identified the development of multiple-resistant E. phyllopogon populations that pose a serious threat to rice production in rice fields in Northeast China, preliminarily confirming that multiple-resistance was likely due to non-target-site resistance mechanisms. These populations of E. phyllopogon are likely to be more difficult to control.
PMID: 37248019
Plants (Basel) , IF:3.935 , 2023 Apr , V12 (9) doi: 10.3390/plants12091854
Ethylene Inhibition Reduces De Novo Shoot Organogenesis and Subsequent Plant Development from Leaf Explants of Solanum betaceum Cav.
Centre for Functional Ecology, TERRA Associate Laboratory, Department of Life Sciences, University of Coimbra, 3000-456 Coimbra, Portugal.; InnovPlantProtect CoLab, 7350-478 Elvas, Portugal.
In de novo shoot organogenesis (DNSO) plant cells develop into new shoots, without the need of an existing meristem. Generally, this process is triggered by wounding and specific growth regulators, such as auxins and cytokinins. Despite the potential significance of the plant hormone ethylene in DNSO, its effect in regeneration processes of woody species has not been thoroughly investigated. To address this gap, Solanum betaceum Cav. was used as an experimental model to explore the role of this hormone on DNSO and potentially extend the findings to other woody species. In this work it was shown that ethylene positively regulates DNSO from tamarillo leaf explants. Ethylene precursors ACC and ethephon stimulated shoot regeneration by increasing the number of buds and shoots regenerated. In contrast, the inhibition of ethylene biosynthesis or perception by AVG and AgNO(3) decreased shoot regeneration. Organogenic callus induced in the presence of ethylene precursors showed an upregulated expression of the auxin efflux carrier gene PIN1, suggesting that ethylene may enhance shoot regeneration by affecting auxin distribution prior to shoot development. Additionally, it was found that the de novo shoot meristems induced in explants in which ethylene biosynthesis and perception was suppressed were unable to further develop into elongated shoots. Overall, these results imply that altering ethylene levels and perception could enhance shoot regeneration efficiency in tamarillo. Moreover, we offer insights into the possible molecular mechanisms involved in ethylene-induced shoot regeneration.
PMID: 37176912
Plants (Basel) , IF:3.935 , 2023 Apr , V12 (9) doi: 10.3390/plants12091843
Identification of Superior Barley Genotypes Using Selection Index of Ideal Genotype (SIIG).
Crop and Horticultural Science Research Department, Fars Agricultural and Natural Resources Research and Education Center, Agricultural Research, Education and Extension Organization (AREEO), Darab P.O. Box 71558-63511, Iran.; Seed and Plant Improvement Institute, Agricultural Research, Education and Extension Organization (AREEO), Karaj P.O. Box 31587-77871, Iran.; Crop and Horticultural Science Research Department, Golestan Agricultural and Natural Resources Research and Education Center, Agricultural Research, Education and Extension Organization (AREEO), Gonbad P.O. Box 49156-77555, Iran.; Crop and Horticultural Science Research Department, Sistan Agricultural and Natural Resources Research and Education Center, Agricultural Research, Education and Extension Organization (AREEO), Zabol P.O. Box 98616-44534, Iran.; Crop and Horticultural Science Research Department, Khuzestan Agricultural and Natural Resources Research and Education Center, Agricultural Research, Education and Extension Organization (AREEO), Ahvaz P.O. Box 61335-3341, Iran.; Department of Mathematical and Statistical Methods, Poznan University of Life Sciences, Wojska Polskiego 28, 60-637 Poznan, Poland.; Department of Genetics, Plant Breeding and Seed Production, Wroclaw University of Environmental and Life Sciences, Grunwaldzki 24A, 53-363 Wroclaw, Poland.; Research Center for Cultivar Testing, Slupia Wielka 34, 63-022 Slupia Wielka, Poland.
The main objective of the study was to evaluate and select the superior barley genotypes based on grain yield and some pheno-morphological traits using a new proposed selection index (SIIG). For this purpose, one-hundred-eight pure and four local cultivars (Norouz, Auxin, Nobahar, and WB-97-11) were evaluated as reference genotypes in four warm regions of Iran, including Ahvaz, Darab, Zabol, and Gonbad, during the 2020-2021 cropping seasons. The results of REML analysis showed that the heritability of all traits (except plant height) was higher in Gonbad than in other environments, while the lowest values were estimated in Ahvaz and Zabol environments. In addition, among the measured traits, the thousand kernel weight and grain filling period showed the highest and lowest values of heritability (0.83 and 0.01, respectively). The results showed that the seed yield of genotypes 1, 108, 3, 86, 5, 87, 19, 16, 15, 56, and 18 was higher than the four reference genotypes, and, on the other hand, the SIIG index of these genotypes was greater than or equal to 0.60. Based on the SIIG discriminator index, 4, 8, 31, and 28 genotypes with values greater than or equal to 0.60 were identified as superior for Darab, Ahvaz, Zabol, and Gonbad environments, respectively. As a conclusion, our results revealed that the SIIG index has ideal potential to identify genotypes with high yield and desirable traits. Therefore, the use of this index can be beneficial in screening better genotypes in the early stages of any breeding program for any crop.
PMID: 37176901
Plants (Basel) , IF:3.935 , 2023 Apr , V12 (9) doi: 10.3390/plants12091779
The Role of IAA in Regulating Root Architecture of Sweetpotato (Ipomoea batatas [L.] Lam) in Response to Potassium Deficiency Stress.
Xuzhou Institute of Agricultural Sciences of Xuhuai District of Jiangsu Province, China/Key Laboratory of Sweet Potato Biology and Genetic Breeding, Ministry of Agriculture/National Agricultural Experimental Station for Soil Quality, Xuzhou 221000, China.; School of Life Sciences, Jiangsu Normal University, Xuzhou 221116, China.
Plants can adapt to the spatial heterogeneity of soil nutrients by changing the morphology and architecture of the root system. Here, we explored the role of auxin in the response of sweetpotato roots to potassium (K(+)) deficiency stress. Two sweetpotato cultivars, Xushu 32 (low-K-tolerant) and Ningzishu 1 (low-K-sensitive), were cultured in low K(+) (0.1 mmol L(-1), LK) and normal K(+) (10 mmol L(-1), CK) nutrient solutions. Compared with CK, LK reduced the dry mass, K(+) content, and K(+) accumulation in the two cultivars, but the losses of Xushu 32 were smaller than those of Ningzishu 1. LK also affected root growth, mainly impairing the length, surface area, forks number, and crossings number. However, Xushu 32 had significantly higher lateral root length, density, and surface area than Ningzishu 1, closely related to the roots' higher indole-3-acetic acid (IAA) content. According to the qPCR results, Xushu 32 synthesized more IAA (via IbYUC8 and IbTAR2) in leaves but transported and accumulated in roots through polar transport (via IbPIN1, IbPIN3, and IbAUX1). It was also associated with the upregulation of auxin signaling pathway genes (IbIAA4 and IbIAA8) in roots. These results imply that IAA participates in the formation of lateral roots and the change in root architecture during the tolerance to low K(+) stress of sweetpotato, thus improving the absorption of K(+) and the formation of biomass.
PMID: 37176837
Plants (Basel) , IF:3.935 , 2023 Apr , V12 (9) doi: 10.3390/plants12091778
Modulation of the Berry Skin Transcriptome of cv. Tempranillo Induced by Water Stress Levels.
Linking Landscape, Environment, Agriculture and Food Research Centre (LEAF), Associated Laboratory TERRA, Instituto Superior de Agronomia, Universidade de Lisboa, 1649-004 Lisboa, Portugal.; INIAV-Instituto Nacional de Investigacao Agraria e Veterinaria, Polo de Inovacao de Dois Portos, 2565-191 Dois Portos, Portugal.
Climate change in the Mediterranean area is making summers warmer and dryer. Grapevine (Vitis vinifera L.) is mostly important for wine production in Mediterranean countries, and the variety Tempranillo is one of the most cultivated in Spain and Portugal. Drought decreases yield and quality and causes important economic losses. As full irrigation has negative effects on quality and water is scarce in this region, deficit irrigation is often applied. In this research, we studied the effects of two deficit irrigation treatments, Sustained Deficit Irrigation (SDI) and Regulated Deficit Irrigation (RDI), on the transcriptome of grape berries at full maturation, through RNAseq. The expression of differentially regulated genes (DEGs) was also monitored through RT-qPCR along berry development. Most transcripts were regulated by water stress, with a similar distribution of up- and down-regulated transcripts within functional categories (FC). Primary metabolism was the more severely affected FC under water stress, followed by signaling and transport. Almost all DEGs monitored were significantly up-regulated by severe water stress at veraison. The modulation of an auxin response repression factor, AUX22D, by water stress indicates a role of this gene in the response to drought. Further, the expression of WRKY40, a TF that regulates anthocyanin biosynthesis, may be responsible for changes in grape quality under severe water stress.
PMID: 37176836
Plants (Basel) , IF:3.935 , 2023 Apr , V12 (8) doi: 10.3390/plants12081687
Comparative Coexpression Analysis of Indole Synthase and Tryptophan Synthase A Reveals the Independent Production of Auxin via the Cytosolic Free Indole.
Department of Biology, Faculty of science, Al-Hussein Bin Talal University, Maan 71111, Jordan.; Department of Agricultural Sciences, AL-Shouback University College, Al-Balqa Applied University, Maan 71911, Jordan.; Department of Applied Biology, Jordan University of Science and Technology, Irbid 22110, Jordan.
Indole synthase (INS), a homologous cytosolic enzyme of the plastidal tryptophan synthase A (TSA), has been reported as the first enzyme in the tryptophan-independent pathway of auxin synthesis. This suggestion was challenged as INS or its free indole product may interact with tryptophan synthase B (TSB) and, therefore, with the tryptophan-dependent pathway. Thus, the main aim of this research was to find out whether INS is involved in the tryptophan-dependent or independent pathway. The gene coexpression approach is widely recognized as an efficient tool to uncover functionally related genes. Coexpression data presented here were supported by both RNAseq and microarray platforms and, hence, considered reliable. Coexpression meta-analyses of Arabidopsis genome was implemented to compare between the coexpression of TSA and INS with all genes involved in the production of tryptophan via the chorismate pathway. Tryptophan synthase A was found to be coexpressed strongly with TSB1/2, anthranilate synthase A1/B1, phosphoribosyl anthranilate transferase1, as well as indole-3-glycerol phosphate synthase1. However, INS was not found to be coexpressed with any target genes suggesting that it may exclusively and independently be involved in the tryptophan-independent pathway. Additionally, annotation of examined genes as ubiquitous or differentially expressed were described and subunits-encoded genes available for the assembly of tryptophan and anthranilate synthase complex were suggested. The most probable TSB subunits expected to interact with TSA is TSB1 then TSB2. Whereas TSB3 is only used under limited hormone conditions to assemble tryptophan synthase complex, putative TSB4 is not expected to be involved in the plastidial synthesis of tryptophan in Arabidopsis.
PMID: 37111910
Plants (Basel) , IF:3.935 , 2023 Apr , V12 (8) doi: 10.3390/plants12081664
Investigation of the Effect of the Auxin Antagonist PEO-IAA on Cannabinoid Gene Expression and Content in Cannabis sativa L. Plants under In Vitro Conditions.
Department of Botany, Faculty of Science, Palacky University Olomouc, 78371 Olomouc, Czech Republic.; Czech Advanced Technology and Research Institute, Palacky University Olomouc, 78371 Olomouc, Czech Republic.; Centre of the Region Hana for Biotechnological and Agricultural Research, Department of Genetic Resources for Vegetables, Medicinal and Special Plants, Crop Research Institute, 78371 Olomouc, Czech Republic.; Department of Biochemistry, Faculty of Science, Palacky University, 78371 Olomouc, Czech Republic.
The in vitro shoot propagation of Cannabis sativa L. is an emerging research area for large-scale plant material production. However, how in vitro conditions influence the genetic stability of maintained material, as well as whether changes in the concentration and composition of secondary metabolites can be expected are aspects that need to be better understood. These features are essential for the standardised production of medicinal cannabis. This work aimed to find out whether the presence of the auxin antagonist alpha-(2-oxo-2-phenylethyl)-1H-indole-3-acetic acid (PEO-IAA) in the culture media influenced the relative gene expression (RGE) of the genes of interest (OAC, CBCA, CBDA, THCA) and the concentrations of studied cannabinoids (CBCA, CBDA, CBC, ∆(9)-THCA, and ∆(9)-THC). Two C. sativa cultivars, 'USO-31' and 'Tatanka Pure CBD', were cultivated by in vitro conditions with PEO-IAA presence and then analysed. The RT-qPCR results indicated that even though some changes in the RGE profiles could be observed, no differences were statistically significant compared with the control variant. The results of the phytochemical analyses demonstrate that although there were some differences from the control variant, only the cultivar 'Tatanka Pure CBD' showed a statistically significant increase (at a statistical significance level alpha = 0.05) in the concentration of the cannabinoid CBDA. In conclusion, it would appear that using PEO-IAA in the culture medium is a suitable approach to improve in vitro cannabis multiplication.
PMID: 37111886
Plants (Basel) , IF:3.935 , 2023 Apr , V12 (8) doi: 10.3390/plants12081624
Exogenous Auxin and Gibberellin on Fluoride Phytoremediation by Eichhornia crassipes.
Department of Agricultural Engineering, Federal University of Vicosa, Vicosa 36570-900, Brazil.; Department of Plant Biology, Federal University of Vicosa, Vicosa 36570-900, Brazil.
High rates of fluorosis were reported worldwide as a result of human consumption of water with fluoride contents. Adjusting fluoride concentration in water as recommended by the World Health Organization (<1.5 mg L(-1)) is a concern and it needs to be conducted through inexpensive, but efficient techniques, such as phytoremediation. The application of phytohormones was investigated as a strategy to improve this process. Thus, the main goal of this research was to evaluate the effect of exogenous auxin and gibberellin on the tropical duckweed Eichhornia crassipes performance for fluoride phytoremediation. Definitive screening and central composite rotatable designs were used for experiments where fluoride concentration (5~15 mg L(-1)), phosphorus concentration (1~10 mg L(-1)), and pH (5~9) were assessed as well throughout 10 days. Fluoride contents were determined in solution and plant tissues by potentiometry. Higher concentrations of fluoride reflected on greater absorptions by plants, though in relative terms removal efficiencies were quite similar for all treatments (~60%). Auxin and acidic conditions favored fluoride removals per mass of plant. Fluoride accumulated mostly in leaves and auxin probably alleviated toxic effects on E. crassipes while gibberellin showed no effect. Therefore, E. crassipes could be employed as a fluoride accumulator plant for water treatment and exogenous auxin may be used to improve the process.
PMID: 37111848
Plants (Basel) , IF:3.935 , 2023 Apr , V12 (8) doi: 10.3390/plants12081594
Dissection of Developmental Programs and Regulatory Modules Directing Endosperm Transfer Cell and Aleurone Identity in the Syncytial Endosperm of Barley.
Department of Physiology and Cell Biology, Leibniz Institute for Plant Genetics and Crop Plant Research (IPK), D-06466 Seeland, Germany.; Department of Molecular Genetics, Leibniz Institute for Plant Genetics and Crop Plant Research (IPK), D-06466 Seeland, Germany.
Endosperm development in barley starts with the formation of a multinucleate syncytium, followed by cellularization in the ventral part of the syncytium generating endosperm transfer cells (ETCs) as first differentiating subdomain, whereas aleurone (AL) cells will originate from the periphery of the enclosing syncytium. Positional signaling in the syncytial stage determines cell identity in the cereal endosperm. Here, we performed a morphological analysis and employed laser capture microdissection (LCM)-based RNA-seq of the ETC region and the peripheral syncytium at the onset of cellularization to dissect developmental and regulatory programs directing cell specification in the early endosperm. Transcriptome data revealed domain-specific characteristics and identified two-component signaling (TCS) and hormone activities (auxin, ABA, ethylene) with associated transcription factors (TFs) as the main regulatory links for ETC specification. On the contrary, differential hormone signaling (canonical auxin, gibberellins, cytokinin) and interacting TFs control the duration of the syncytial phase and timing of cellularization of AL initials. Domain-specific expression of candidate genes was validated by in situ hybridization and putative protein-protein interactions were confirmed by split-YFP assays. This is the first transcriptome analysis dissecting syncytial subdomains of cereal seeds and provides an essential framework for initial endosperm differentiation in barley, which is likely also valuable for comparative studies with other cereal crops.
PMID: 37111818
Plants (Basel) , IF:3.935 , 2023 Apr , V12 (7) doi: 10.3390/plants12071542
Dynamics of Endogenous Auxin and Its Role in Somatic Embryogenesis Induction and Progression in Cork Oak.
Pollen Biotechnology of Crop Plants Group, Biological Research Center Margarita Salas, CIB-CSIC, Ramiro de Maeztu 9, 28040 Madrid, Spain.; Department of Genetics, Microbiology and Physiology, Complutense University of Madrid, 28040 Madrid, Spain.
Somatic embryogenesis (SE) is a feasible in vitro regeneration system with biotechnological applications in breeding programs, although, in many forest species, SE is highly inefficient, mainly due to their recalcitrance. On the other hand, SE represents a valuable model system for studies on cell reprogramming, totipotency acquisition, and embryogenic development. The molecular mechanisms that govern the transition of plant somatic cells to embryogenic cells are largely unknown. There is increasing evidence that auxins mediate this transition and play a key role in somatic embryo development, although data on woody species are very limited. In this study, we analyzed the dynamics and possible role of endogenous auxin during SE in cork oak (Quercus suber L.). The auxin content was low in somatic cells before cell reprogramming, while it increased after induction of embryogenesis, as revealed by immunofluorescence assays. Cellular accumulation of endogenous auxin was also detected at the later stages of somatic embryo development. These changes in auxin levels correlated with the expression patterns of the auxin biosynthesis (QsTAR2) and signaling (QsARF5) genes, which were upregulated after SE induction. Treatments with the inhibitor of auxin biosynthesis, kynurenine, reduced the proliferation of proembryogenic masses and impaired further embryo development. QsTAR2 and QsARF5 were downregulated after kynurenine treatment. Our findings indicate a key role of endogenous auxin biosynthesis and signaling in SE induction and multiplication, as well as somatic embryo development of cork oak.
PMID: 37050168
Plants (Basel) , IF:3.935 , 2023 Apr , V12 (7) doi: 10.3390/plants12071534
An Efficient Method of Pennisetum x advena 'Rubrum' Plantlets Production Using the Temporary Immersion Bioreactor Systems and Agar Cultures.
Section of Horticultural Economics, Institute of Horticultural Sciences, Warsaw University of Life Sciences-SGGW, 02-787 Warsaw, Poland.; Department of Biometry, Institute of Agriculture, Warsaw University of Life Sciences-SGGW, 02-787 Warsaw, Poland.; Department of Environmental Protection and Dendrology, Institute of Horticultural Sciences, Warsaw University of Life Sciences-SGGW, 02-787 Warsaw, Poland.
The aim of this study is to develop an efficient method for micropropagation of Pennisetum x advena 'Rubrum'. Agar cultures containing Murashige and Skoog (MS) medium supplemented with 6-benzyl-amino-purine (BAP) in various concentrations (0.5 mg/L to 2 mg/L) and a temporary immersion bioreactor system (TIS) using liquid medium MS with an addition of 1 mg/L BAP were tested. Rooting was performed using (1/2) MS medium supplemented with different auxin combinations (indole-3-butyric acid IBA and alpha-naphthalene acetic acid NAA) and activated charcoal. The TIS method was found to be the most efficient, producing 36.9 new plants within four weeks. The resulting plantlets were thin and bright green in color, with no signs of hyperhydricity. The most suitable agar medium yielded 19.5 new plants within eight weeks. For rooting, (1/2) MS supplemented with 0.5 mg/L IBA and 0.5 mg/L NAA exhibited an 84% rooting rate, whereas the addition of activated charcoal inhibited rooting.
PMID: 37050161
Gene , IF:3.688 , 2023 Jun , V871 : P147434 doi: 10.1016/j.gene.2023.147434
Comparative transcriptome analysis reveals hormone, transcriptional and epigenetic regulation involved in prickle formation in Zanthoxylum armatum.
Chongqing Key Laboratory of Economic Plant Biotechnology, Chongqing University of Arts and Sciences, Chongqing 402160, China. Electronic address: sabrina-0810@hotmail.com.; College of Horticulture and Gardening, Yangtze University, Jingzhou 434025, China. Electronic address: Caozhengyan1998@163.com.; College of Horticulture and Gardening, Yangtze University, Jingzhou 434025, China. Electronic address: wupeiyin718@163.com.; College of Biology and Food Engineering, Chongqing Three Georges University, Chongqing 404100, China. Electronic address: liuyn9523@163.com.; Chongqing Key Laboratory of Economic Plant Biotechnology, Chongqing University of Arts and Sciences, Chongqing 402160, China. Electronic address: loujuan1981@163.com.; Chongqing Key Laboratory of Economic Plant Biotechnology, Chongqing University of Arts and Sciences, Chongqing 402160, China. Electronic address: 18580561843@163.com.; Chongqing Key Laboratory of Economic Plant Biotechnology, Chongqing University of Arts and Sciences, Chongqing 402160, China. Electronic address: sunxiaofan2022@163.com.; Chongqing Key Laboratory of Economic Plant Biotechnology, Chongqing University of Arts and Sciences, Chongqing 402160, China. Electronic address: ztmysishuo@163.com.; Chongqing Key Laboratory of Economic Plant Biotechnology, Chongqing University of Arts and Sciences, Chongqing 402160, China. Electronic address: chenzexiong1979@163.com.
Zanthoxylum armatum is an evergreen plant with high economical and medicinal values. The presence of prickles on stems and leaves is undesirable for them make picking difficult. To date, little is known of prickle formation in Z. armatum. Herein, the morphological and molecular features of prickle initiation in prickless (WC) and three types of prickly Z. armatum were characterized. Compared to WC, the levels of cytokinin and auxin were increased, while GA and JA declined in prickly Z. armatum. Transcriptome analysis identified 6258 differentially expressed genes (DEGs) between prickless and prickly Z. armatum. Among them, several DEGs related to hormone metabolism and signaling, including LOG7, CKX3, AHK1, three DELLAs, six JAZs and TIR1, were candidate genes involved in prickle formation. Transcription factors associated with prickle formation were screened, including MYB6-1/MYB6-2, WER, GL3-2, SPL4/5, SOC1, and SCL32. Of them, MYB6-1 and WER might negatively regulate prickles initiation via interacting with GL3-2. Additionally, the histone acetylation and DNA methylation levels, the transcripts of histone acetyltransferase/deacetylase and DNA methyltransferases showed significant differences between prickless and prickly plants, indicating their involvements in prickle initiation. These findings illustrate the regulation of prickle formation might be mediated by phytohormones (especially cytokinin), transcription factors and epigenetic modifications in Z. armatum.
PMID: 37068692
J Plant Physiol , IF:3.549 , 2023 Jun , V285 : P153995 doi: 10.1016/j.jplph.2023.153995
Integrative transcriptome and metabolome revealed the molecular mechanism of Bacillus megaterium BT22-mediated growth promotion in Arabidopsis thaliana.
Biophysics Group, Biomedical Center, Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou, 730000, China; University of Chinese Academy of Sciences, Beijing, 100049, China.; College of Life Science, Lanzhou University, Lanzhou, 730000, China.; College of Life Science and Engineering, Lanzhou University of Technology, Lanzhou, 730050, China.; Biophysics Group, Biomedical Center, Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou, 730000, China; University of Chinese Academy of Sciences, Beijing, 100049, China; Kejin Innovation Institute of Heavy Ion Beam Biological Industry, Baiyin, 730900, China.; College of Pharmacy, Gansu University of Chinese Medicine, Lanzhou, 730000, China.; Lueyang County Jinxiu Agricultural Development Co., Ltd, Lueyang, Hanzhong, 724300, China.; Biophysics Group, Biomedical Center, Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou, 730000, China; University of Chinese Academy of Sciences, Beijing, 100049, China; Kejin Innovation Institute of Heavy Ion Beam Biological Industry, Baiyin, 730900, China. Electronic address: libinzhoulz@gmail.com.
Plant growth-promoting rhizobacteria (PGPR) can promote plant growth and protect plants from pathogens, which contributes to sustainable agricultural development. Several studies have reported their beneficial characteristics in facilitating plant growth and development and enhancing plant stress resistance through different mechanisms. However, there is still a challenge to study the molecular mechanism of plant response to PGPR. We integrated the transcriptome and metabolome of Arabidopsis thaliana (Arabidopsis) to understand its responses to the inoculation with an isolated PGPR strain (BT22) of Bacillus megaterium. Fresh shoot weight, dry shoot weight and leaf number of Arabidopsis were increased by BT22 treatment, showing a positive growth-promoting effect. According multi-omics analysis, 878 differentially expressed genes (296 up-regulated, 582 down-regulated) and 139 differentially expressed metabolites (66 up-regulated, 73 down-regulated) response to BT22 inoculation. GO enrichment results indicate that the up-regulated genes mainly enriched in the regulation of growth and auxin response pathways. In contrast, the down-regulated genes mainly enriched in wounding response, jasmonic acid and ethylene pathways. BT22 inoculation regulated plant hormone signal transduction of Arabidopsis, including auxin and cytokinin response genes AUX/IAA, SAUR, and A-ARR related to cell enlargement and cell division. The contents of nine flavonoids and seven phenylpropanoid metabolites were increased, which help to induce systemic resistance in plants. These results suggest that BT22 promoted Arabidopsis growth by regulating plant hormone homeostasis and inducing metabolome reprogramming.
PMID: 37163868
J Plant Physiol , IF:3.549 , 2023 Apr , V283 : P153947 doi: 10.1016/j.jplph.2023.153947
Overexpression of cotton Trihelix transcription factor GhGT-3b_A04 enhances resistance to Verticillium dahliae and affects plant growth in Arabidopsis thaliana.
Zhengzhou Research Base, State Key Laboratory of Cotton Biology, Zhengzhou University, Zhengzhou, 450001, China; State Key Laboratory of Cotton Biology, Institute of Cotton Research, Chinese Academy of Agricultural Sciences, Anyang, 455000, China. Electronic address: mhaoming666@163.com.; Zhengzhou Research Base, State Key Laboratory of Cotton Biology, Zhengzhou University, Zhengzhou, 450001, China; State Key Laboratory of Cotton Biology, Institute of Cotton Research, Chinese Academy of Agricultural Sciences, Anyang, 455000, China. Electronic address: zhangwenqing45@163.com.; Zhengzhou Research Base, State Key Laboratory of Cotton Biology, Zhengzhou University, Zhengzhou, 450001, China; State Key Laboratory of Cotton Biology, Institute of Cotton Research, Chinese Academy of Agricultural Sciences, Anyang, 455000, China. Electronic address: ljyuan0426@163.com.; Zhengzhou Research Base, State Key Laboratory of Cotton Biology, Zhengzhou University, Zhengzhou, 450001, China; State Key Laboratory of Cotton Biology, Institute of Cotton Research, Chinese Academy of Agricultural Sciences, Anyang, 455000, China. Electronic address: yangjiaxiang9803@163.com.; Zhengzhou Research Base, State Key Laboratory of Cotton Biology, Zhengzhou University, Zhengzhou, 450001, China; State Key Laboratory of Cotton Biology, Institute of Cotton Research, Chinese Academy of Agricultural Sciences, Anyang, 455000, China. Electronic address: yangsx0721@163.com.; Zhengzhou Research Base, State Key Laboratory of Cotton Biology, Zhengzhou University, Zhengzhou, 450001, China; State Key Laboratory of Cotton Biology, Institute of Cotton Research, Chinese Academy of Agricultural Sciences, Anyang, 455000, China. Electronic address: jiabing1814@126.com.; Zhengzhou Research Base, State Key Laboratory of Cotton Biology, Zhengzhou University, Zhengzhou, 450001, China; State Key Laboratory of Cotton Biology, Institute of Cotton Research, Chinese Academy of Agricultural Sciences, Anyang, 455000, China. Electronic address: sjkow513@163.com.; Zhengzhou Research Base, State Key Laboratory of Cotton Biology, Zhengzhou University, Zhengzhou, 450001, China; State Key Laboratory of Cotton Biology, Institute of Cotton Research, Chinese Academy of Agricultural Sciences, Anyang, 455000, China. Electronic address: wuman2004@163.com.; Zhengzhou Research Base, State Key Laboratory of Cotton Biology, Zhengzhou University, Zhengzhou, 450001, China; State Key Laboratory of Cotton Biology, Institute of Cotton Research, Chinese Academy of Agricultural Sciences, Anyang, 455000, China. Electronic address: peiwenfeng1988@163.com.; Zhengzhou Research Base, State Key Laboratory of Cotton Biology, Zhengzhou University, Zhengzhou, 450001, China; State Key Laboratory of Cotton Biology, Institute of Cotton Research, Chinese Academy of Agricultural Sciences, Anyang, 455000, China. Electronic address: mjj1699@126.com.; Zhengzhou Research Base, State Key Laboratory of Cotton Biology, Zhengzhou University, Zhengzhou, 450001, China; State Key Laboratory of Cotton Biology, Institute of Cotton Research, Chinese Academy of Agricultural Sciences, Anyang, 455000, China. Electronic address: 1551016063@qq.com.; Department of Plant and Environmental Sciences, New Mexico State University, Las Cruces, 880033, USA. Electronic address: jinzhang@nmsu.edu.; Zhengzhou Research Base, State Key Laboratory of Cotton Biology, Zhengzhou University, Zhengzhou, 450001, China; State Key Laboratory of Cotton Biology, Institute of Cotton Research, Chinese Academy of Agricultural Sciences, Anyang, 455000, China. Electronic address: wangli07-2@163.com.; Zhengzhou Research Base, State Key Laboratory of Cotton Biology, Zhengzhou University, Zhengzhou, 450001, China; State Key Laboratory of Cotton Biology, Institute of Cotton Research, Chinese Academy of Agricultural Sciences, Anyang, 455000, China. Electronic address: yujw666@hotmail.com.
Verticillium wilt is a soil-borne fungal disease that severely affects cotton fiber yield and quality. Herein, a cotton Trihelix family gene, GhGT-3b_A04, was strongly induced by the fungal pathogen Verticillium dahliae. Overexpression of the gene in Arabidopsis thaliana enhanced the plant's resistance to Verticillium wilt but inhibited the growth of rosette leaves. In addition, the primary root length, root hair number, and root hair length increased in GhGT-3b_A04-overexpressing plants. The density and length of trichomes on the rosette leaves also increased. GhGT-3b_A04 localized to the nucleus, and transcriptome analysis revealed that it induced gene expression for salicylic acid synthesis and signal transduction and activated gene expression for disease resistance. The gene expression for auxin signal transduction and trichome development was reduced in GhGT-3b_A04-overexpressing plants. Our results highlight important regulatory genes for Verticillium wilt resistance and cotton fiber quality improvement. The identification of GhGT-3b_A04 and other important regulatory genes can provide crucial reference information for future research on transgenic cotton breeding.
PMID: 36898190
Protoplasma , IF:3.356 , 2023 Apr doi: 10.1007/s00709-023-01855-5
Genome-wide investigation of ARF transcription factor gene family and its responses to abiotic stress in Coix (Coix lacryma-jobi L.).
Key Laboratory of Plant Secondary Metabolism Regulation in Zhejiang Province, College of Life Sciences and Medicine, Zhejiang Sci-Tech University, Hangzhou, 310018, Zhejiang, China.; Zhejiang Chinese Medical University, Hangzhou, 310053, Zhejiang, China.; Songyang Institute of Zhejiang Chinese Medical University, Lishui, 323400, China.; State Key Laboratory of Dao-Di Herbs, Beijng, 100700, China.; Key Laboratory of Plant Secondary Metabolism Regulation in Zhejiang Province, College of Life Sciences and Medicine, Zhejiang Sci-Tech University, Hangzhou, 310018, Zhejiang, China. wangdk@zstu.edu.cn.
Auxin response factor (ARF) is an important transcription factor that regulates the expression of auxin-responsive genes by direct binding to their promoters, which play a central role in plant growth, development, and response to abiotic stresses. The availability of the entire Coix (Coix lacryma-jobi L.) genome sequence provides an opportunity to investigate the characteristics and evolutionary history of the ARF gene family in this medicine and food homology plant for the first time. In this study, a total of 27 ClARF genes were identified based on the genome-wide sequence of Coix. Twenty-four of the 27 ClARF genes were unevenly distributed on 8 chromosomes except Chr 4 and 10, and the remaining three genes (ClARF25-27) were not assigned to any chromosome. Most of the ClARF proteins were predicted to be localized to the nucleus, except ClARF24, which was localized to both the plasma membrane and nucleus. Twenty-seven ClARFs were clustered into six subgroups based on the phylogenetic analysis. Duplication analysis showed that segmental duplication, rather than tandem duplications promoting the expansion of the ClARF gene family. Synteny analysis showed that purifying selection might have been a primary driving force in the development of the ARF gene family in Coix and other investigated cereal plants. The prediction of the cis element of the promoter showed that 27 ClARF genes contain several stress response elements, suggesting that ClARFs might be involved in the abiotic stress response. Expression profile analysis shows that 27 ClARF genes were all expressed in the root, shoot, leaf, kernel, glume, and male flower of Coix with varying expression levels. Furthermore, qRT-PCR analyses revealed that the majority of ClARFs members were upregulated or downregulated in response to hormone treatment and abiotic stress. The current study expands our understanding of the functional roles of ClARFs in stress responses and provides basic information for the ClARF genes.
PMID: 37041371
Protoplasma , IF:3.356 , 2023 May , V260 (3) : P955-966 doi: 10.1007/s00709-022-01826-2
Phytotoxicity and the molecular response in yttrium oxide nanoparticle-treated Arabidopsis thaliana seedlings.
Higher Education Key Laboratory of Plant Molecular and Environment Stress Response, Shanxi Normal University, Taiyuan, 030000, Shanxi, China.; College of Life Sciences, Shanxi Normal University, Taiyuan, 030000, Shanxi, China.; Higher Education Key Laboratory of Plant Molecular and Environment Stress Response, Shanxi Normal University, Taiyuan, 030000, Shanxi, China. jinlin_feng@163.com.; College of Life Sciences, Shanxi Normal University, Taiyuan, 030000, Shanxi, China. jinlin_feng@163.com.; Higher Education Key Laboratory of Plant Molecular and Environment Stress Response, Shanxi Normal University, Taiyuan, 030000, Shanxi, China. hhwrsl@163.com.; College of Life Sciences, Shanxi Normal University, Taiyuan, 030000, Shanxi, China. hhwrsl@163.com.
Due to the widespread application of rare earth oxide nanoparticles in various fields, their release into the environment is inevitable, and their potential toxicity and ecological impact have become a concern. Yttrium oxide nanoparticles are important rare earth oxide nanoparticles; however, their impact on plants and the molecular mechanism underlying their influence on plant growth and development are unclear. In this study, we found that yttrium oxide nanoparticles at concentrations exceeding 2 mM significantly inhibited the growth of Arabidopsis seedlings. Using Arabidopsis marker lines for auxin signaling, we found that the application of yttrium oxide nanoparticles resulted in disordered auxin signaling in root cells. Auxin signaling in the cells of the quiescent center and columella stem cells decreased, while auxin signaling in the cells of the stele was enhanced. In addition, trypan blue staining showed that yttrium oxide nanoparticles induced root cell death. Transcriptome analysis showed that the nanoparticles specifically inhibited the expression of lignin synthesis-related genes, activated the MAPK signaling pathway, and enhanced the ethylene and abscisic acid signaling pathways in plants. This study demonstrates the phytotoxicity of yttrium oxide nanoparticles at the molecular level in Arabidopsis, and it provides a new perspective on how plants respond to rare earth oxide stress.
PMID: 36445485
Protoplasma , IF:3.356 , 2023 May , V260 (3) : P723-739 doi: 10.1007/s00709-022-01808-4
Insights of auxin signaling F-box genes in wheat (Triticum aestivum L.) and their dynamic expression during the leaf rust infection.
Department of Bioengineering and Biotechnology, Birla Institute of Technology, Mesra, Ranchi, 835215, Jharkhand, India.; Division of Genetics, ICAR-Indian Agricultural Research Institute, New Delhi, 110012, India.; Department of Bioengineering and Biotechnology, Birla Institute of Technology, Mesra, Ranchi, 835215, Jharkhand, India. kmukhopadhyay@bitmesra.ac.in.
The TRANSPORT INHIBITOR RESPONSE 1/AUXIN SIGNALING F-BOX (TIR1/AFB) protein serves as auxin receptor and links with Aux/IAA repressor protein leading to its degradation via SKP-Cullin-F box (SCF(TIR1/AFB)) complex in the auxin signaling pathway. Present study revealed 11 TIR1/AFB genes in wheat by genome-wide search using AFB HMM profile. Phylogenetic analysis clustered these genes in two classes. Several phytohormone, abiotic, and biotic stress responsive cis-elements were detected in promoter regions of TIR1/AFB genes. These genes were localized on homoeologous chromosome groups 2, 3, and 5 showing orthologous relation with other monocot plants. Most genes were interrupted by introns and the gene products were localized in cytoplasm, nucleus, and cell organelles. TaAFB3, TaAFB5, and TaAFB8 had nuclear localization signals. The evolutionary constraint suggested paralogous sister pairs and orthologous genes went through strong purifying selection process and are slowly evolving at protein level. Functional annotation revealed all TaAFB genes participated in auxin activated signaling pathway and SCF-mediated ubiquitination process. Furthermore, in silico expression study revealed their diverse expression profiles during various developmental stages in different tissues and organs as well as during biotic and abiotic stress. QRT-PCR based studies suggested distinct expression pattern of TIR1-1, TIR1-3, TaAFB1, TaAFB2, TaAFB3, TaAFB4, TaAFB5, TaAFB7, and TaAFB8 displaying maximum expression at 24 and 48 h post inoculation in both susceptible and resistant near isogenic wheat lines infected with leaf rust pathogen. Importantly, this also reflects coordinated responses in expression patterns of wheat TIR1/AFB genes during progression stages of leaf rust infection.
PMID: 36100728
PLoS One , IF:3.24 , 2023 , V18 (5) : Pe0286140 doi: 10.1371/journal.pone.0286140
Comparative analysis of microRNA expression profiles in shoot and root tissues of contrasting rice cultivars (Oryza sativa L.) with different salt stress tolerance.
Institute of Genome Research, Vietnam Academy of Science and Technology, Hanoi, Vietnam.; Graduate University of Science and Technology, Vietnam Academy of Science and Technology, Hanoi, Vietnam.
Rice is the second-most important primary crop in the world and one of the most susceptible crops to salt stress. Soil salinization hinders seedling growth and decreases crop yield by inducing ionic and osmotic imbalances, photosynthesis disturbances, cell wall alterations, and gene expression inhibition. Plants have developed a range of defense mechanisms to adapt to salt stress. One of the most effective means is to make use of plant microRNAs (miRNAs) as post-transcriptional regulators to regulate the expression of developmental genes in order to mitigate the detrimental effects of salt stress. In this study, the miRNA sequencing data between two contrasting rice cultivars, salt-tolerant Doc Phung (DP) and salt-sensitive IR28 seedlings, were compared under control and salt stress (150 mM NaCl) conditions to determine the salt stress-responsive miRNAs. Comparative analysis of miRNA sequencing data detected a total of 69 differentially expressed miRNAs in response to salt stress treatment. Among them, 18 miRNAs from 13 gene families, MIR156, MIR164, MIR167, MIR168, MIR171, MIR396, MIR398, MIR1432, MIR1846, MIR1857, MIR1861, MIR3979, and MIR5508, were identified to be specifically and significantly expressed in the shoot and root tissues of DP seedlings. Gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses further revealed that these detected miRNAs regulate a range of essential biological and stress response processes, including gene transcription, osmotic homeostasis, root formation, ROS scavenger synthesis, and auxin and abscisic acid signaling pathways. Our findings provide more insight into the miRNA-mediated responsive mechanisms of rice under salt stress and should benefit the improvement of salt stress tolerance in rice.
PMID: 37224116
Plant Biol (Stuttg) , IF:3.081 , 2023 Apr , V25 (3) : P411-419 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 signalling pathways remains fragmented. In this study, the effects of NO on calmodulin (CAM), calcium protein kinase (CPK), content of phytohormones and secondary metabolites in canola plants under salinity stress were investigated. We applied 100 muM sodium nitroprusside as an NO source to canola plants grown under saline (100 mM NaCl) and non-saline conditions at the vegetative stage. Plant growth was negatively affected by salinity, but exogenous NO treatment improved growth. NO caused a significant increase in activity of CAT, SOD and POX through their enhanced gene expression in stressed canola. Salinity-responsive genes, namely CAM and CPK, were induced by NO in plants grown under salinity. NO application enhanced phenolic compounds, such as gallic acid and coumaric acid and flavonoid compound,s catechin, diadzein and kaempferol, in plants subjected to salinity. NO treatment enhanced abscisic acid and brassinosteroids but decreased auxin and gibberellin in stressed canola plants. The impacts of NO in improving stress tolerance in canola required CAM and CPK. Also, NO signalling re-established the phytohormone balance and resulted in enhanced tolerance to salt stress. Furthermore, NO improved salinity tolerance in canola by increasing enzymatic and non-enzymatic antioxidant content.
PMID: 36779525
PeerJ , IF:2.984 , 2023 , V11 : Pe15212 doi: 10.7717/peerj.15212
Genome-wide identification and co-expression network analysis of Aux/IAA gene family in Salvia miltiorrhiza.
Hunan Provincial Key Laboratory for Synthetic Biology of Traditional Chinese Medicine, School of Pharmaceutical Sciences, Hunan University of Medicine, Huaihua, Hunan, China.
The auxin/indole-3-acetic acid (Aux/IAA) gene family serves as a principal group of genes responsible for modulating plant growth and development through the auxin signaling pathway. Despite the significance of this gene family, the identification and characterization of members within the well-known Chinese medicinal herb Salvia miltiorrhiza (S. miltiorrhiza) have not been thoroughly investigated. In this study, we employed bioinformatics methods to identify 23 Aux/IAA genes within the genome of S. miltiorrhiza. These genes were classified into typical IAA and atypical IAA based on their domain structure. Our analysis of the promoter regions revealed that the expression of these genes is regulated not only by auxins, but also by other hormones and environmental factors. Furthermore, we found that the expression patterns of these genes varied across various tissues of S. miltiorrhiza. While our initial hypothesis suggested that the primary function of these genes was the interaction between SmIAA and ARF, gene co-expression network analysis revealed that they are also influenced by various other transcription factors, such as WRKY and ERF. The findings establish a sturdy basis for future investigations into the function of the Aux/IAA gene family and exhibit promising prospects for enhancing the genetics of this medicinal flora and its associated species.
PMID: 37090108
PeerJ , IF:2.984 , 2023 , V11 : Pe15150 doi: 10.7717/peerj.15150
Effects of plant age on antioxidant activity and endogenous hormones in Alpine Elymus sibiricus of the Tibetan Plateau.
Key Laboratory of Grassland Ecosystem of Ministry of Education, College of Grassland Science, Gansu Agricultural University, Lanzhou, Gansu Province, China.; Gansu Grassland Technical Extension Station, Lanzhou, Gansu Province, China.
Elymus sibiricus L. is a perennial forage species that has potential to serve as a forage source in livestock grazing systems. However, E. sibiricus has been shown to have a rapid and substantial reduction of aboveground biomass and seed yield after 3 or 4 years and an accelerated aging process. To determine possible aging mechanisms, we planted E. sibiricus seeds in triplicate blocks in 2012, 2015, and 2016, respectively, and harvested samples of leaves and roots at the jointing and heading stages in 2018 and 2019 to determine oxidative indices and endogenous hormones. The fresh aboveground biomass of 4- and 5-year old plants declined by 34.2% and 52.4% respectively compared with 3-year old plants, and the seed yield declined by 12.7% and 34.1%, respectively. The water content in leaves was 51.7%, 43.3%, and 35.6%, and net photosynthesis was 7.73, 6.35, and 2.08 micromol/m(2).s in 3-, 4-, and 5-year old plants, respectively. The superoxide anion radical generation rate in leaves and roots did not show any aging pattern. There was a non-significant increase in malondialdehyde concentration with plant age, particularly in leaves and roots at the heading stage in 2019. The superoxide dismutase activity showed a declining trend with age of plant roots at the jointing stage in both 2018 and 2019. The peroxidase activity declined with plant age in both leaves and roots, for example, and the catalase activity in roots 4- and 7-year old plants declined by 13.8% and 0.85%, respectively, compared to 3-year old plants at the heading stage in 2018. Therefore, the reduced capacity of the antioxidant system may lead to oxidative stress during plant aging process. Overall, the concentrations of plant hormones, auxin (IAA), gibberellin (GA), zeatin (ZT), and abscisic acid (ABA) were significantly lower in roots than in leaves. The IAA concentration in leaves and roots exhibited different patterns with plant age. The ZT concentrations in leaves of 3-year old plants was 2.39- and 2.62-fold of those in 4- and 7-year old plants, respectively at the jointing stage, and in roots, the concentration declined with plant age. The changes in the GA concentration with plant age varied between the physiological stages and between years. The ABA concentrations appeared to increase with plant age, particularly in leaves. In conclusion, the aging process of E. sibiricus was apparently associated with an increase in oxidative stress, a decrease of ZT and an increase of ABA, particularly in roots. These findings highlight the effects of plant age on the antioxidant and endogenous hormone activity of E. sibiricus. However, these plant age-related trends showed variations between plant physiological stages and between harvest years that needs to be researched in the future to develop strategies to manage this forage species.
PMID: 37065700
Transgenic Res , IF:2.788 , 2023 Apr , V32 (1-2) : P77-93 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
Chem Biodivers , IF:2.408 , 2023 May , V20 (5) : Pe202201243 doi: 10.1002/cbdv.202201243
22-Oxocholestanes SPGP4 and SPGP8: in Silico and in Vitro Study as Activators of Plant Growth Promotion.
Laboratorio de Elucidacion y Sintesis en Quimica Organica, Facultad de Ciencias Quimicas, Benemerita Universidad Autonoma de Puebla, 72570, Puebla, Mexico.; Centro de Investigacion en Biotecnologia Aplicada-IPN, Tepetitla de Lardizabal, 90700, Tlaxcala, Mexico.; Laboratorio de Sintesis y Modificacion de Productos Naturales, Facultad de Ciencias Quimicas, Benemerita Universidad Autonoma de Puebla, 72570, Puebla, Mexico.
The 22-oxocholestanes compounds have shown an outstanding plant growth promoting activity; they have similar bioactivity as brassinosteroids, so they are normally named as brassinosteroid analogs thinking that they also impact on the known receptor BRI1. However, in silico studies allow us to predict interactions with other receptors and thus it's possible to evaluate them, through receptors of gibberellins, auxins, jasmonates, strigolactones and the protein associated with the BRI1 gene. This article describes the bioactivity of structures SPGP4 and SPGP8 as plant growth-promoting compounds. Both structures present coupling energies and interactions at the same level as epibrassinolide in the protein associated with BRI1 gene. Additionally, interactions through the auxin pathway and to strigolactone receptor were found using selected tests. In the rice lamina tilt, a higher effect was obtained when SPGP4 and SPGP8 were compared to epibrassinolide, although in a lesser level vis a vis to homobrassinolide. In the same way, when SPGP4 and SPGP8 were tested in the Growth Root Model an activity as strigonolactones was observed, enhancing the relationship between the main and secondary roots. However, the growth of coleptiles, when applying auxins, compounds SPGP4 and SPGP8 did not reach the same level as controls. In the tests associated to gibberellins and jasmonic acid, an increased bioactivity was observed, although this behavior was not reflected from the in silico study, possibly due to secondary signaling cascades. This work demonstrates that the 22-oxocolestane compounds SPGP4 and SPGP8 could be used as plant growth hormones, promoting several pathways.
PMID: 37062704
3 Biotech , IF:2.406 , 2023 May , V13 (5) : P132 doi: 10.1007/s13205-023-03546-7
Regulatory networks of hormone-involved transcription factors and their downstream pathways during somatic embryogenesis of Arabidopsis thaliana.
Department of Biotechnology and Plant Breeding, Faculty of Agriculture, Ferdowsi University of Mashhad, Mashhad, Iran. GRID: grid.411301.6. ISNI: 0000 0001 0666 1211
Somatic embryogenesis (SE) depends on a variety of developmental pathways that are influenced by several environmental factors. Therefore, it is important to understand the relationship between environmental and genetic factors by identifying the gene networks involved in SE through gene set enrichment analysis (GSEA). For determination of SE effective transcription factors, upstream sequences of core-enriched genes were analyzed. The results indicated that response to hormones is one of the biological pathways activated by the enriched TFs at all stages of somatic embryogenesis and about half of the hormonal pathways were enriched. On the fifth day after 2,4-Dichlorophenoxyacetic acid (2,4-D) treatment, the activity of hormone-affecting genes reached its maximum. At this time, more transcription factors regulated the enriched genes compared to the other stages of somatic embryogenesis. MYBs, AT-HOOKs, and HSFs are the main families of transcription factors which affect core-enriched genes during SE. CCA1, PRR7, and TOC1 and their related genes at the center of protein-protein interaction of SE-key transcription factors, involved in the regulation of the circadian clock. Gene expression analysis of CCA1, PRR7, and TOC1 revealed that the genes involved in circadian clock reached their maximum activity when embryonic cells formed. Also, auxin response elements were identified at the upstream of SE-circadian clock transcription factors, indicating that they might mediate between auxin signaling and SE-related hormonal pathways as well as SE marker genes such as AGL15, BBM, and LECs. Based on these results, it is possible that the cellular circadian rhythm activates various developmental pathways under the influence of auxin signal transduction and their interactions determine the induction of somatic embryogenesis. According to the results of this study, modifying pathways affected by SE-related transcription factors such as circadian rhythm may result in cell reprogramming and increase somatic embryogenesis efficiency. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s13205-023-03546-7.
PMID: 37091499
Physiol Mol Biol Plants , IF:2.391 , 2023 Apr , V29 (4) : P513-523 doi: 10.1007/s12298-023-01309-5
Beneficial effects of red and blue light on potato leaf antioxidant capacity and tuber bulking.
Lanzhou, 730070 People's Republic of China State Key Laboratory of Aridland Crop Science, Gansu Agricultural University. GRID: grid.411734.4. ISNI: 0000 0004 1798 5176; Lanzhou, 730070 People's Republic of China College of Agronomy, Gansu Agricultural University. GRID: grid.411734.4. ISNI: 0000 0004 1798 5176
Artificial light application is an effective method for promoting potato production in indoor facilities. In this study, we assessed the effects of different combinations of red (R) and blue (B) light application on potato leaf and tuber growth. Potato plantlets were transplanted under W (white light, control), RB(5-5) (50% R + 50% B), RB(3-7) (30% R + 70% B to 70% R + 30% B) and RB(1-9) (10% R + 90% B to 90% R + 10% B), and ascorbic acid (AsA) metabolism in leaves and cytokinin (CTK), auxin (indole-3-acetic acid, IAA), abscisic acid (ABA), and gibberellin (GA) levels in tubers were measured. At 50 days of treatment, potato leaves had significantly higher L-galactono-1,4-lactone dehydrogenase (GalLDH) activity and utilized AsA faster under RB(1-9) treatment than under RB(3-7) treatment. CTK/IAA and ABA/GA ratios in large tubers under W treatment did not differ significantly from those under RB(1-9) treatment, which had higher levels than those under RB(5-5) and RB(3-7) treatment at 50 days. However, under RB(1-9) treatment, total leaf area decreased rapidly from 60 to 75 days compared with plants under RB(3-7) treatment. Tuber dry weight per plant under W and RB(5-5) treatment approached a plateau at 75 days. At 80 days, RB(3-7) treatment significantly improved ascorbate peroxidase, monodehydroascorbate reductase, dehydroascorbate reductase, and glutathione reductase activity compared with RB(1-9) treatment. RB(1-9) treatment with a high ratio of blue light increased CTK/IAA and ABA/GA to improve tuber bulking at 50 days, while RB(3-7) treatment with a high ratio of red light stimulated AsA metabolic pathway to delay leaf oxidation and maintain tuber biomass accumulation at 80 days. For the indoor potato cultivation, RB(3-7) treatment had a higher proportion of medium-sized tubers, thus being a suitable light treatment.
PMID: 37187773
Mol Biol Rep , IF:2.316 , 2023 Jun , V50 (6) : P5319-5343 doi: 10.1007/s11033-023-08429-x
Comparative transcriptome analysis of Zea mays upon mechanical wounding.
Department of Botany, Hansraj College, University of Delhi, Delhi, India.; J C Bose Center for Plant Genomics, Hansraj College, University of Delhi, Delhi, India.; Department of Botany, North-Eastern Hill University, Shillong, India.; Department of Zoology, Deshbandhu College, University of Delhi, New Delhi, India. iksingh@db.du.ac.in.; Department of Botany, Hansraj College, University of Delhi, Delhi, India. archanasingh@hrc.du.ac.in.; J C Bose Center for Plant Genomics, Hansraj College, University of Delhi, Delhi, India. archanasingh@hrc.du.ac.in.; Delhi School of Climate Change and Sustainability, Institution of Eminence, Maharishi Karnad Bhawan, University of Delhi, New Delhi, India. archanasingh@hrc.du.ac.in.
BACKGROUND: Mechanical wounding (MW) is mainly caused due to high wind, sand, heavy rains and insect infestation, leading to damage to crop plants and an increase in the incidences of pathogen infection. Plants respond to MW by altering expression of genes, proteins, and metabolites that help them to cope up with the stress. METHODS AND RESULTS: In order to characterize maize transcriptome in response to mechanical wounding, a microarray analysis was executed. The study revealed 407 differentially expressed genes (DEGs) (134 upregulated and 273 downregulated). The upregulated genes were engaged in protein synthesis, transcription regulation, phytohormone signaling-mediated by salicylic acid, auxin, jasmonates, biotic and abiotic stress including bacterial, insect, salt and endoplasmic reticulum stress, cellular transport, on the other hand downregulated genes were involved in primary metabolism, developmental processes, protein modification, catalytic activity, DNA repair pathways, and cell cycle. CONCLUSION: The transcriptome data present here can be further utilized for understanding inducible transcriptional response during mechanical injury and their purpose in biotic and abiotic stress tolerance. Furthermore, future study concentrating on the functional characterization of the selected key genes (Bowman Bird trypsin inhibitor, NBS-LRR-like protein, Receptor-like protein kinase-like, probable LRR receptor-like ser/thr-protein kinase, Cytochrome P450 84A1, leucoanthocyanidin dioxygenase, jasmonate O-methyltransferase) and utilizing them for genetic engineering for crop improvement is strongly recommended.
PMID: 37155015
Mol Biol Rep , IF:2.316 , 2023 Apr , V50 (4) : P3617-3632 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
Antonie Van Leeuwenhoek , IF:2.271 , 2023 May doi: 10.1007/s10482-023-01828-x
Lysinibacillus spp.: an IAA-producing endospore forming-bacteria that promotes plant growth.
Universidad de Antioquia, Instituto de Biologia, Medellin, Colombia. manuel.pantojag@udea.edu.co.; Facultad de Ciencias Agropecuarias, Unilasallista Corporacion Universitaria, Caldas - Antioquia, Colombia. manuel.pantojag@udea.edu.co.; Plant Response Biotech, Plant City, FL, USA.; United States Department of Agriculture, Agricultural Research Service, National Center for Agricultural Utilization Research, Crop Bioprotection Research Unit, 1815 N University, Peoria, IL, USA.; Universidad de Antioquia, Instituto de Biologia, Medellin, Colombia.
Lysinibacillus is a bacterial genus that has generated recent interest for its biotechnological potential in agriculture. Strains belonging to this group are recognized for their mosquitocidal and bioremediation activity. However, in recent years some reports indicate its importance as plant growth promoting rhizobacteria (PGPR). This research sought to provide evidence of the PGP activity of Lysinibacillus spp. and the role of the indole-3-acetic acid (IAA) production associated with this activity. Twelve Lysinibacillus spp. strains were evaluated under greenhouse conditions, six of which increased the biomass and root architecture of corn plants. In most cases, growth stimulation was evident at 10(8) CFU/mL inoculum concentration. All strains produced IAA with high variation between them (20-70 microg/mL). The bioinformatic identification of predicted genes associated with IAA production allowed the detection of the indole pyruvic acid pathway to synthesize IAA in all strains; additionally, genes for a tryptamine pathway were detected in two strains. Extracellular filtrates from all strain's cultures increased the corn coleoptile length in an IAA-similar concentration pattern, which demonstrates the filtrates had an auxin-like effect on plant tissue. Five of the six strains that previously showed PGPR activity in corn also promoted the growth of Arabidopsis thaliana (col 0). These strains induced changes in root architecture of Arabidopsis mutant plants (aux1-7/axr4-2), the partial reversion of mutant phenotype indicated the role of IAA on plant growth. This work provided solid evidence of the association of Lysinibacillus spp. IAA production with their PGP activity, which constitutes a new approach for this genus. These elements contribute to the biotechnological exploration of this bacterial genus for agricultural biotechnology.
PMID: 37138159
Plant Signal Behav , IF:2.247 , 2023 Dec , V18 (1) : P2207845 doi: 10.1080/15592324.2023.2207845
Mendel-200: Pea as a model system to analyze hormone-mediated stem elongation.
I- Cultiver, Inc, Manteca, CA 95336 & Department of Plant Biology, Carnegie Institution for Science, Stanford, CA, USA.
In a recent Review Article on Gregor Mendel's (1822-1884) work with pea (Pisum sativum)-plants, it was proposed that this crop species should be re-vitalized as a model organism for the study of cell- and organ growth. Here, we describe the effect of exogenous gibberellic acid (GA(3)) on the growth of the second internode in 4-day-old light-grown pea seedlings (Pisum sativum, large var. "Senator"). lnjection of glucose into the internode caused a growth-promoting effect similar to that of the hormone GA(3). Imbibition of dry pea seeds in GA(3), or water as control, resulted in a drastic enhancement in organ development in this tall variety. Similar results were reported for dwarf peas. These "classical" experimental protocols are suitable to study the elusive effect of gibberellins (which act in coordination with auxin) on the regulation of plant development at the biochemical and molecular levels.
PMID: 37166004
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
Folia Microbiol (Praha) , IF:2.099 , 2023 Apr doi: 10.1007/s12223-023-01051-1
Evaluation of drought-tolerant endophytic fungus Talaromyces purpureogenus as a bioinoculant for wheat seedlings under normal and drought-stressed circumstances.
Department of Biotechnology, Thapar Institute of Engineering and Technology, Patiala, 147004, Punjab, India.; Department of Biotechnology, Thapar Institute of Engineering and Technology, Patiala, 147004, Punjab, India. ssaxena@thapar.edu.
The present work is aimed to hypothesize that fungal endophytes associated with wheat (Triticum aestivum L.) plants can play a variety of roles in biotechnology including plant growth. Out of 67 fungal isolates, five maximum drought-tolerant isolates were used to check their various plant growth-promoting traits, antioxidants, and antifungal activities under secondary screening. Fungal isolate #8TAKS-3a exhibited the maximum drought tolerance capacity and potential to produce auxin, gibberellic acid, ACC deaminase, phosphate, zinc solubilization, ammonia, siderophore, and extracellular enzyme activities followed by #6TAKR-1a isolate. In terms of antioxidant activities, #8TAKS-3a culture also showed maximum DPPH scavenging, total antioxidant, and NO-scavenging activities. However, #6TAKR-1a exhibited maximum total flavonoid content, total phenolic content, and Fe-reducing power and also the highest growth inhibition of Aspergillus niger (ITCC 6152) and Colletotrichum sp. (ITCC 6152). Based on morphological characters and multi-locus phylogenetic analysis of the nuc rDNA internal transcribed spacer region (ITS1-5.8S-ITS2 = ITS), beta-tubulin (TUB 2), and RNA polymerase II second largest subunit (RPB2) genes, potent fungal isolate #8TAKS-3a was identified as Talaromyces purpureogenus. Under the in vitro conditions, T. purpureogenus (#8TAKS-3a) was used as a bioinoculant that displayed a significant increase in various physio-biochemical growth parameters under normal and stressed conditions (p < 0.05). Our results indicate that drought stress-tolerant T. purpureogenus can be further used for field testing as a growth promoter.
PMID: 37076748
Biosci Biotechnol Biochem , IF:2.043 , 2023 May , V87 (6) : P592-604 doi: 10.1093/bbb/zbad029
Analysis of the effect of each plant hormone on the maturation of woodland strawberry fruit in auxin-induced parthenocarpic fruit.
Kihara Institute for Biological Research, Yokohama City University, Kanagawa, Japan.; Graduate School of Agricultural and Life Sciences, The University of Tokyo, Tokyo, Japan.; Faculty of Agriculture, Utsunomiya University, Tochigi, Japan.
Evaluation of individual roles of plant hormones in fruit development is difficult because various plant hormones function simultaneously. In this study, to analyze the effect of plant hormones on fruit maturation one by one, plant hormones were applied to auxin-induced parthenocarpic woodland strawberry (Fragaria vesca) fruits. As a result, auxin, gibberellin (GA), and jasmonate, but, not abscisic acid and ethylene increased the proportion of ultimately mature fruits. So far, to produce comparable fruit with pollinated fruit in size, auxin with GA treatment was required in woodland strawberry. Picrolam (Pic), the most potent auxin in inducing parthenocarpic fruit, induced fruit which is comparable in size with pollinated fruit without GA. The endogenous GA level and the result of the RNA interference analysis of the main GA biosynthetic gene suggest that a basal level of endogenous GA is essential for fruit development. The effect of other plant hormones was also discussed.
PMID: 36914217
Genes Genomics , IF:1.839 , 2023 Apr , V45 (4) : P401-412 doi: 10.1007/s13258-022-01321-1
Transcriptomic profiling of the cold stress and recovery responsiveness of two contrasting Guizhou HE rice genotypes.
Guizhou Rice Research Institute, Guizhou Provincial Academy of Agricultural Sciences, Guiyang, 550006, China.; College of Agriculture, Guizhou University, Guiyang, 550025, China.; Guizhou Rice Research Institute, Guizhou Provincial Academy of Agricultural Sciences, Guiyang, 550006, China. 13984033281@139.com.
BACKGROUND: At the seed germination stage, rice is sensitive to cold stress, which adversely affects its growth and development. Guizhou HE rice comprises several different landraces, most of which are cold tolerant. OBJECTIVE: To identify differentially expressed genes and molecular mechanism underlying the cold tolerance of Guizhou HE. METHODS: Two Guizhou HE genotypes, AC44 (cold-sensitive) and AC96 (cold-tolerant), which exhibit opposite phenotypes in response to cold treatment at the seed germination stage were used. Comprehensive gene expressions of AC44 and AC96 under 4 degrees C cold treatment and subsequent recovery conditions were comparatively analyzed by RNA sequencing. RESULTS: Overall, 11,082 and 7749 differentially expressed genes were detected in AC44 and AC96, respectively. Comparative transcriptome analysis demonstrated that, compared with AC44, AC96 presented fewer upregulated and downregulated genes. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analyses demonstrated that AC96 presented more upregulated GO terms, especially terms associated with biological processes. However, AC44 presented more terms related to cellular components, mainly chloroplasts. Moreover, DEGs related to the auxin signaling pathway (including ARF and IAA family members) and transcription factors (including members of the F-box, bZIP, basic helix-loop-helix [bHLH], and MYB-like transcription factor families) were found to be expressed specifically in AC96; thus, these DEGs may be responsible for the cold tolerance of AC96. CONCLUSIONS: These findings present information about the cold tolerance mechanism of Guizhou HE rice at the germination stage, providing valuable resources and candidate genes for breeding cold-tolerant rice genotypes.
PMID: 36469228
J Genet Genomics , 2023 May doi: 10.1016/j.jgg.2023.05.001
Nitric oxide-mediated S-nitrosylation of IAA17 protein in intrinsically disordered region represses auxin signaling.
State Key Laboratory of Plant Genomics, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China; University of Chinese Academy of Sciences, Beijing 100049, China; Department of Biology, Duke University, Durham, NC 27008, USA. Electronic address: hongwei.jing@duke.edu.; State Key Laboratory of Plant Genomics, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China; University of Chinese Academy of Sciences, Beijing 100049, China; Department of Neurobiology, Duke University Medical Center, Durham, NC 27008, USA.; Department of Biochemistry and Molecular Biophysics, Washington University School of Medicine, St. Louis, MO 63110, USA; Center for Biomolecular Condensates (CBC), Washington University in St. Louis, St. Louis MO 63130, USA.; State Key Laboratory of Plant Genomics, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China; University of Chinese Academy of Sciences, Beijing 100049, China.; State Key Laboratory of Plant Genomics, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China.; Department of Biology, Duke University, Durham, NC 27008, USA.; Department of Biological Systems Engineering, Virginia Tech, Blacksburg, VA 24061, USA.; Department of Biological Systems Engineering, Virginia Tech, Blacksburg, VA 24061, USA; The Translational Plant Sciences Center (TPSC), Virginia Tech, Blacksburg, VA 24061, USA.; State Key Laboratory of Plant Genomics, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China; University of Chinese Academy of Sciences, Beijing 100049, China; CAS Center for Excellence in Molecular Plant Sciences, Chinese Academy of Sciences, Beijing 100101, China. Electronic address: jrzuo@genetics.ac.cn.
The phytohormone auxin plays crucial roles in nearly every aspect of plant growth and development. Auxin signaling is activated through the phytohormone-induced proteasomal degradation of the Auxin/INDOLE-3-ACETIC ACID (Aux/IAA) family of transcriptional repressors. Notably, many auxin-modulated physiological processes are also regulated by nitric oxide (NO) that executes its biological effects predominantly through protein S-nitrosylation at specific cysteine residues. However, little is known about the molecular mechanisms in regulating the interactive NO and auxin networks. Here, we show that NO represses auxin signaling by inhibiting IAA17 protein degradation. NO induces the S-nitrosylation of Cys-70 located in the intrinsically disordered region of IAA17, which inhibits the TIR1-IAA17 interaction and consequently the proteasomal degradation of IAA17. The accumulation of a higher level of IAA17 attenuates auxin response. Moreover, an IAA17(C70W) nitrosomimetic mutation renders the accumulation of a higher level of the mutated protein, thereby causing partial resistance to auxin and defective lateral root development. Taken together, these results suggest that S-nitrosylation of IAA17 at Cys-70 inhibits its interaction with TIR1, thereby negatively regulating auxin signaling. This study provides unique molecular insights into the redox-based auxin signaling in regulating plant growth and development.
PMID: 37187411
J Genet Genomics , 2023 Apr doi: 10.1016/j.jgg.2023.04.008
PIFs interact with SWC6 to regulate H2A.Z deposition and photomorphogenesis in Arabidopsis.
Shanghai Key Laboratory of Plant Molecular Sciences, College of Life Sciences, Shanghai Normal University, Shanghai 200234, China.; School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai 200240, China.; Shanghai Key Laboratory of Plant Molecular Sciences, College of Life Sciences, Shanghai Normal University, Shanghai 200234, China. Electronic address: zhileimao@shnu.edu.cn.
Light is an essential environmental signal perceived by a board range of photoreceptors in plants. Among them, the red/far-red light receptor phytochromes function to promote photomorphogenesis, which is critical to the survival of seedlings after seeds germination. The bHLH transcription factors PHYTOCHROME-INTERACTING FACTORs (PIFs) are the pivotal direct downstream components of phytochromes. H2A.Z is a highly conserved histone variant regulating gene transcription, and its incorporation into nucleosomes is catalyzed by SWR1 complex, in which SWC6 and ARP6 serve as core subunits. Here, we show that PIFs physically interact with SWC6 in vitro and in vivo, leading to the disassociation of HY5 from SWC6. SWC6 and ARP6 regulate hypocotyl elongation partly through PIFs in red light. PIFs and SWC6 co-regulate the expression of auxin-responsive genes such as IAA6, IAA19, IAA20 and IAA29, and repress H2A.Z deposition at IAA6 and IAA19 in red light. Based on previous studies and our findings, we propose that PIFs inhibit photomorphogenesis, at least in part, through repression of H2A.Z deposition at auxin-responsive genes mediated by the interactions of PIFs with SWC6 and promotion of their expression in red light.
PMID: 37120038
Plant Commun , 2023 Apr : P100604 doi: 10.1016/j.xplc.2023.100604
The miR167-OsARF12 module regulates grain filling and grain size downstream of miR159.
Collaborative Innovation Center of Henan Grain Crops, Henan Agricultural University, Zhengzhou 450002, China; Key Laboratory of Rice Biology in Henan Province, Henan Agricultural University, Zhengzhou 450002, China; Henan Engineering Laboratory of Rice, Henan Agricultural University, Zhengzhou 450002, China.; Joint Center for Single Cell Biology/School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai 200240, China.; Department of Biotechnology, Sharda University, Greater Noida, 201306, India.; Institute of Paulownia, Henan Agricultural University, Zhengzhou, Henan 450002, China.; Department of Biological Sciences, Michigan Technological University, Houghton, MI 49931, USA.; Joint Center for Single Cell Biology/School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai 200240, China. Electronic address: lypengting@163.com.; Collaborative Innovation Center of Henan Grain Crops, Henan Agricultural University, Zhengzhou 450002, China; Key Laboratory of Rice Biology in Henan Province, Henan Agricultural University, Zhengzhou 450002, China; Henan Engineering Laboratory of Rice, Henan Agricultural University, Zhengzhou 450002, China; College of Agriculture, Guizhou University, 550025, China. Electronic address: lypengting@163.com.; Collaborative Innovation Center of Henan Grain Crops, Henan Agricultural University, Zhengzhou 450002, China; Key Laboratory of Rice Biology in Henan Province, Henan Agricultural University, Zhengzhou 450002, China; Henan Engineering Laboratory of Rice, Henan Agricultural University, Zhengzhou 450002, China. Electronic address: lypengting@163.com.
Grain weight and quality are always determined by the grain filling. Plant miRNAs have drawn attention as key targets for regulating grain size and yield. Yet the mechanisms underlying the regulation of grain size are largely unclear due to the complex networks controlling this trait. Our earlier studies proved that the suppressed expression of miR167 (STTM/MIM167) substantially increased grain weight. In a field test, the increased yield up to 12.90%-21.94% due to the significantly enhanced grain filling rate. Biochemical and genetic analyses reveal the regulatory effects of miR159 on miR167 expression. Further analysis indicates that OsARF12 is the major mediator of miR167 in regulating rice grain filling. Expectedly, over expressing OsARF12 could resemble the phenotype of STTM/MIM167 plants with respect to grain weight and grain filling rate. Upon in-depth analysis, we found that OsARF12 activates OsCDKF;2 expressions by directly binding to the TGTCGG motif in the promoter region. Flow cytometric analysis in young panicles of plants overexpressing OsARF12 and cell number examination of cdkf;2 mutants verify that OsARF12 positively regulates grain filling and grain size by targeting OsCDKF;2. Moreover, RNA-seq result suggests that miR167-OsARF12 module is involved in the cell development process and hormone pathways. Additionally, plants overexpressing OsARF12 or cdkf;2 mutants present enhanced or reduced sensitivity to exogenous auxin and brassinosteroid (BR) treatments, confirming that OsCDKF;2 targeting by OsARF12 mediates auxin and BR signaling. Our results reveal that miR167-OsARF12 module works downstream of miR159 to regulate rice grain filling and grain size by OsCDKF;2 through controlling cell division and mediating auxin and BR signals.
PMID: 37085993