Mol Plant , IF:13.164 , 2022 Aug doi: 10.1016/j.molp.2022.08.008
The regeneration factors ERF114 and ERF115 regulate auxin-mediated lateral root development in response to mechanical cues.
Department of Plant Biotechnology and Bioinformatics, Ghent University, Ghent, B-9052, Belgium; VIB Center for Plant Systems Biology, Ghent, B-9052, Belgium.; Department of Plant Biology, Linnean Center for Plant Biology, Swedish University of Agricultural Sciences, Almas alle 5, 756 51, Uppsala, Sweden.; Department of Plant Biochemistry, Center for Plant Molecular Biology (ZMBP), University of Tubingen, 72076 Tubingen, Germany.; Department of Plant Biotechnology and Bioinformatics, Ghent University, Ghent, B-9052, Belgium; VIB Center for Plant Systems Biology, Ghent, B-9052, Belgium. Electronic address: lieven.deveylder@psb.vib-ugent.be.
Plants show an unparalleled regenerative capacity, allowing them to survive severe stress conditions, such as injury, herbivory attack and harsh weather conditions. This potential not only replenishes tissues and restores damaged organs, but can also give rise to whole plant bodies. Despite the intertwined nature of development and regeneration, upstream cues and signaling mechanisms that commonly activate organogenesis are largely unknown. Here, we demonstrate that next to being activators of regeneration, ETHYLENE RESPONSE FACTOR 114 (ERF114) and ERF115 govern developmental growth in the absence of wounding or injury. Increased ERF114 and ERF115 activity enhances auxin sensitivity, which is correlated with enhanced xylem maturation and lateral root formation, whereas their knockout results in a decrease in lateral roots. Moreover, we provide evidence that mechanical cues contribute to ERF114 and ERF115 expression in correlation with BZR1-mediated brassinosteroid signaling under both regenerative and developmental conditions. Antagonistically, cell wall integrity surveillance via mechanosensory FERONIA signaling suppresses their expression under both conditions. Our data suggest a molecular framework in which cell wall signals and mechanical strains regulate organ development and regenerative responses via ERF114 and ERF115 mediated auxin signaling.
PMID: 36030378
Dev Cell , IF:12.27 , 2022 Aug , V57 (16) : P2009-2025.e6 doi: 10.1016/j.devcel.2022.07.003
Organ-specific COP1 control of BES1 stability adjusts plant growth patterns under shade or warmth.
Fundaciomicronn Instituto Leloir, Instituto de Investigaciones Bioquimicas de Buenos Aires, Consejo Nacional de Investigaciones Cientificas y Tecnicas, 1405 Buenos Aires, Argentina.; Department of Biological Sciences, Korea Advanced Institute of Science and Technology, Daejeon 34141, South Korea.; Institute of Synthetic Biology and Cluster of Excellence in Plant Sciences, University of Dusseldorf, 40225 Dusseldorf, Germany.; Laboratory of Growth Regulators, Palacky University and Institute of Experimental Botany, Czech Academy of Sciences, Olomouc, Czech Republic.; Instituto de Biologiotaa Molecular y Celular de Plantas, Consejo Superior de Investigaciones Cientificas, Universidad Politecnica de Valencia, 46022 Valencia, Spain.; Fundaciomicronn Instituto Leloir, Instituto de Investigaciones Bioquimicas de Buenos Aires, Consejo Nacional de Investigaciones Cientificas y Tecnicas, 1405 Buenos Aires, Argentina; Instituto de Investigaciones Fisiologicas y Ecologicas Vinculadas a la Agricultura, Facultad de Agronomia, Universidad de Buenos Aires, Consejo Nacional de Investigaciones Cientificas y Tecnicas, 1417 Buenos Aires, Argentina. Electronic address: casal@ifeva.edu.ar.
Under adverse conditions such as shade or elevated temperatures, cotyledon expansion is reduced and hypocotyl growth is promoted to optimize plant architecture. The mechanisms underlying the repression of cotyledon cell expansion remain unknown. Here, we report that the nuclear abundance of the BES1 transcription factor decreased in the cotyledons and increased in the hypocotyl in Arabidopsis thaliana under shade or warmth. Brassinosteroid levels did not follow the same trend. PIF4 and COP1 increased their nuclear abundance in both organs under shade or warmth. PIF4 directly bound the BES1 promoter to enhance its activity but indirectly reduced BES1 expression. COP1 physically interacted with the BES1 protein, promoting its proteasome degradation in the cotyledons. COP1 had the opposite effect in the hypocotyl, demonstrating organ-specific regulatory networks. Our work indicates that shade or warmth reduces BES1 activity by transcriptional and post-translational regulation to inhibit cotyledon cell expansion.
PMID: 35901789
EMBO J , IF:11.598 , 2022 Aug : Pe110682 doi: 10.15252/embj.2022110682
Salicylic acid-activated BIN2 phosphorylation of TGA3 promotes Arabidopsis PR gene expression and disease resistance.
Ministry of Education Key Laboratory for Bio-Resource and Eco-Environment, College of Life Science, State Key Laboratory of Hydraulics and Mountain River Engineering, Sichuan University, Chengdu, China.; School of Life Science and Engineering, Southwest University of Science and Technology, Mianyang, China.
The plant defense hormone, salicylic acid (SA), plays essential roles in immunity and systemic acquired resistance. Salicylic acid induced by the pathogen is perceived by the receptor nonexpressor of pathogenesis-related genes 1 (NPR1), which is recruited by TGA transcription factors to induce the expression of pathogenesis-related (PR) genes. However, the mechanism by which post-translational modifications affect TGA's transcriptional activity by salicylic acid signaling/pathogen infection is not well-established. Here, we report that the loss-of-function mutant of brassinosteroid insensitive2 (BIN2) and its homologs, bin2-3 bil1 bil2, causes impaired pathogen resistance and insensitivity to SA-induced PR gene expression, whereas the gain-of-function mutant, bin2-1, exhibited enhanced SA signaling and immunity against the pathogen. Our results demonstrate that salicylic acid activates BIN2 kinase, which in turn phosphorylates TGA3 at Ser33 to enhance TGA3 DNA binding ability and NPR1-TGA3 complex formation, leading to the activation of PR gene expression. These findings implicate BIN2 as a new component of salicylic acid signaling, functioning as a key node in balancing brassinosteroid-mediated plant growth and SA-induced immunity.
PMID: 35950443
Plant Cell , IF:11.277 , 2022 Aug doi: 10.1093/plcell/koac245
The deubiquitinating enzymes UBP12 and UBP13 positively regulate recovery after carbon starvation by modulating BES1 stability in Arabidopsis thaliana.
Ministry of Education Key Laboratory for Bio-Resource and Eco-Environment, College of Life Science, State Key Laboratory of Hydraulics and Mountain River Engineering, Sichuan University, Chengdu, P.R.China.; Department of Genetics, Development, and Cell Biology, Plant Sciences Institute, Iowa State University, Ames, IA, USA.
BRI1-EMS-SUPPRESSOR1 (BES1), a core transcription factor in the brassinosteroid (BR) signaling pathway, primarily regulates plant growth and development by influencing BR-regulated gene expression. Several E3 ubiquitin ligases regulate BES1 stability, but little is known about BES1 deubiquitination, which antagonizes E3 ligase-mediated ubiquitination to maintain BES1 homeostasis. Here, we report that two Arabidopsis thaliana deubiquitinating enzymes, UBIQUITIN-SPECIFIC PROTEASE12 (UBP12) and UBP13, interact with BES1. UBP12 and UBP13 removed ubiquitin from polyubiquitinated BES1 to stabilize both phosphorylated and dephosphorylated forms of BES1. A double mutant, ubp12-2w ubp13-3, lacking UBP12 and UBP13 function showed both BR-deficient and BR-insensitive phenotypes, whereas transgenic plants overexpressing UBP12 or UBP13 exhibited an increased BR response. Expression of UBP12 and UPB13 was induced during recovery after carbon starvation, which led to BES1 accumulation and quick recovery of stressed plants. Our work thus establishes a mechanism by which UBP12 and UBP13 regulate BES1 protein abundance to enhance BR-regulated growth during recovery after carbon starvation.
PMID: 35944221
Plant Cell , IF:11.277 , 2022 Jul doi: 10.1093/plcell/koac222
Activation by inhibition: How redox signaling tunes brassinosteroid responses.
Assistant Features Editor, The Plant Cell, American Society of Plant Biologists, USA.; School of Biological Sciences, Institute of Molecular Plant Sciences, University of Edinburgh, UK.
PMID: 35916654
Plant Cell , IF:11.277 , 2022 Jul doi: 10.1093/plcell/koac203
Adenosine monophosphate deaminase modulates BIN2 activity through hydrogen peroxide-induced oligomerization.
Department of Plant Biotechnology and Bioinformatics, Ghent University, 9052 Ghent, Belgium.; Center for Plant Systems Biology, VIB, 9052 Ghent, Belgium.; Plant Developmental Biology, Wageningen University Research, 6708 PB Wageningen, The Netherlands.
The Arabidopsis thaliana GSK3-like kinase, BRASSINOSTEROID-INSENSITIVE2 (BIN2) is a key negative regulator of brassinosteroid (BR) signaling and a hub for crosstalk with other signaling pathways. However, the mechanisms controlling BIN2 activity are not well understood. Here we performed a forward genetic screen for resistance to the plant-specific GSK3 inhibitor bikinin and discovered that a mutation in the ADENOSINE MONOPHOSPHATE DEAMINASE (AMPD)/EMBRYONIC FACTOR1 (FAC1) gene reduces the sensitivity of Arabidopsis seedlings to both bikinin and BRs. Further analyses showed that AMPD modulates BIN2 activity by regulating its oligomerization in a hydrogen peroxide (H2O2)-dependent manner. Exogenous H2O2 induced the formation of BIN2 oligomers with a decreased kinase activity and an increased sensitivity to bikinin. By contrast, AMPD activity inhibition reduces the cytosolic reactive oxygen species (ROS) levels and the amount of BIN2 oligomers, correlating with the decreased sensitivity of Arabidopsis plants to bikinin and BRs. Furthermore, we showed that BIN2 phosphorylates AMPD to possibly alter its function. Our results reveal the existence of a H2O2 homeostasis-mediated regulation loop between AMPD and BIN2 that fine-tunes the BIN2 kinase activity to control plant growth and development.
PMID: 35876813
Plant Cell , IF:11.277 , 2022 Jul doi: 10.1093/plcell/koac196
Rice DWARF AND LOW-TILLERING and the homeodomain protein OSH15 interact to regulate internode elongation via orchestrating brassinosteroid signaling and metabolism.
National Key Facility for Crop Gene Resources and Genetic Improvement, Institute of Crop Sciences, Chinese Academy of Agricultural Sciences, Beijing 100081, China.; State Key Laboratory of Plant Genomics and Center for Plant Gene Research (Beijing), Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China.; Southern Regional Collaborative Innovation Center for Grain and Oil Crops in China, Hunan Agricultural University, Changsha 410128, China.; National Nanfan Research Institute, Chinese Academy of Agricultural Sciences, Sanya 572024, China.
Brassinosteroid (BR) phytohormones play crucial roles in regulating internode elongation in rice (Oryza sativa). However, the underlying mechanism remains largely unclear. The dwarf and low-tillering (dlt) mutant is a mild BR-signaling-defective mutant. Here we identify two dlt enhancers that show more severe shortening of the lower internodes compared to the uppermost internode (IN1). Both mutants carry alleles of ORYZA SATIVA HOMEOBOX 15 (OSH15), the founding gene for dwarf6-type mutants, which have shortened lower internodes but not IN1. Consistent with the mutant phenotype, OSH15 expression is much stronger in lower internodes, particularly in IN2, than IN1. The osh15 single mutants have impaired BR sensitivity accompanied by enhanced BR synthesis in seedlings. DLT physically interacts with OSH15 to co-regulate many genes in seedlings and internodes. OSH15 targets and promotes expression of the BR receptor gene BR INSENSITIVE1 (OsBRI1), and DLT facilitates this regulation in a dosage-dependent manner. In osh15, dlt and osh15 dlt, BR levels are higher in seedlings and panicles, but unexpectedly lower in internodes compared with wild type. Taken together, our results suggest that DLT interacts with OSH15, which functions in the lower internodes, to modulate rice internode elongation via orchestrating BR signaling and metabolism.
PMID: 35789396
Proc Natl Acad Sci U S A , IF:11.205 , 2022 Aug , V119 (34) : Pe2208978119 doi: 10.1073/pnas.2208978119
OCTOPUS regulates BIN2 to control leaf curvature in Chinese cabbage.
State Key Laboratory of North China Crop Improvement and Regulation, Key Laboratory of Vegetable Germplasm Innovation and Utilization of Hebei, Collaborative Innovation Center of Vegetable Industry in Hebei, College of Horticulture, Hebei Agricultural University, 071000 Baoding, China.
Heading is one of the most important agronomic traits for Chinese cabbage crops. During the heading stage, leaf axial growth is an essential process. In the past, most genes predicted to be involved in the heading process have been based on leaf development studies in Arabidopsis. No genes that control leaf axial growth have been mapped and cloned via forward genetics in Chinese cabbage. In this study, we characterize the inward curling mutant ic1 in Brassica rapa ssp. pekinensis and identify a mutation in the OCTOPUS (BrOPS) gene by map-based cloning. OPS is involved in phloem differentiation in Arabidopsis, a functionalization of regulating leaf curvature that is differentiated in Chinese cabbage. In the presence of brassinosteroid (BR) at the early heading stage in ic1, the mutation of BrOPS fails to sequester brassinosteroid insensitive 2 (BrBIN2) from the nucleus, allowing BrBIN2 to phosphorylate and inactivate BrBES1, which in turn relieves the repression of BrAS1 and results in leaf inward curving. Taken together, the results of our findings indicate that BrOPS positively regulates BR signaling by antagonizing BrBIN2 to promote leaf epinastic growth at the early heading stage in Chinese cabbage.
PMID: 35969746
New Phytol , IF:10.151 , 2022 Jul doi: 10.1111/nph.18404
Integration of multi-omics data reveals interplay between brassinosteroid and Target of Rapamycin Complex signaling in Arabidopsis.
Department of Plant Pathology and Microbiology, Iowa State University, Ames, IA, 50011, USA.; Department of Genetics, Development and Cell Biology, Iowa State University, Ames, IA, 50011, USA.; Department of Biology, Duke University, Durham, NC, 27708, USA.; USDA-ARS Cereal Disease Laboratory, University of Minnesota, St Paul, MN, 55108, USA.; Plant Sciences Institute, Iowa State University, Ames, IA, 50011, USA.
Brassinosteroids (BRs) and Target of Rapamycin Complex (TORC) are two major actors coordinating plant growth and stress responses. Brassinosteroids function through a signaling pathway to extensively regulate gene expression and TORC is known to regulate translation and autophagy. Recent studies have revealed connections between these two pathways, but a system-wide view of their interplay is still missing. We quantified the level of 23 975 transcripts, 11 183 proteins, and 27 887 phosphorylation sites in wild-type Arabidopsis thaliana and in mutants with altered levels of either BRASSINOSTEROID INSENSITIVE 2 (BIN2) or REGULATORY ASSOCIATED PROTEIN OF TOR 1B (RAPTOR1B), two key players in BR and TORC signaling, respectively. We found that perturbation of BIN2 or RAPTOR1B levels affects a common set of gene-products involved in growth and stress responses. Furthermore, we used the multi-omic data to reconstruct an integrated signaling network. We screened 41 candidate genes identified from the reconstructed network and found that loss of function mutants of many of these proteins led to an altered BR response and/or modulated autophagy activity. Altogether, these results establish a predictive network that defines different layers of molecular interactions between BR- or TORC-regulated growth and autophagy.
PMID: 35892179
New Phytol , IF:10.151 , 2022 Aug , V235 (4) : P1455-1469 doi: 10.1111/nph.18228
Pan-brassinosteroid signaling revealed by functional analysis of NILR1 in land plants.
College of Life Sciences, Shaanxi Normal University, Xi'an, 710119, China.
Brassinosteroid (BR) signaling has been identified from the ligand BRs sensed by the receptor Brassinosteroid Insensitive 1 (BRI1) to the final activation of Brassinozole Resistant 1/bri1 EMS-Suppressor 1 through a series of transduction events. Extensive studies have been conducted to characterize the role of BR signaling in various biological processes. Our previous study has shown that Excess Microsporocytes 1 (EMS1) and BRI1 control different aspects of plant growth and development via conserved intracellular signaling. Here, we reveal that another receptor, NILR1, can complement the bri1 mutant in the absence of BRs, indicating a pathway that resembles BR signaling activated by NILR1. Genetic analysis confirms the intracellular domains of NILR1, BRI1 and EMS1 have a common signal output. Furthermore, we demonstrate that NILR1 and BRI1 share the coreceptor BRI1 Associated Kinase 1 and substrate BSKs. Notably, the NILR1-mediated downstream pathway is conserved across land plants. In summary, we provide evidence for the signaling cascade of NILR1, suggesting pan-brassinosteroid signaling initiated by a group of distant receptor-ligand pairs in land plants.
PMID: 35570834
Cell Rep , IF:9.423 , 2022 Aug , V40 (7) : P111235 doi: 10.1016/j.celrep.2022.111235
A VQ-motif-containing protein fine-tunes rice immunity and growth by a hierarchical regulatory mechanism.
State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing 100193, China.; Institute of Crop Sciences, Chinese Academy of Agricultural Sciences, Beijing 100081, China.; State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing 100193, China; College of Agronomy, Hunan Agricultural University, Changsha 410128, China.; Key Laboratory of Plant Functional Genomics of the Ministry of Education/ Jiangsu Key Laboratory of Crop Genomics and Molecular Breeding, Agricultural College of Yangzhou University, Yangzhou 225009, China.; College of Agronomy, Hunan Agricultural University, Changsha 410128, China.; National Key Laboratory of Crop Genetic Improvement, National Center of Plant Gene Research, Huazhong Agricultural University, Wuhan 430070, China.; Department of Plant Pathology, The Ohio State University, Columbus, OH 43210, USA.; Institute of Crop Sciences, Chinese Academy of Agricultural Sciences, Beijing 100081, China; Hainan Yazhou Bay Seed Laboratory/National Nanfan Research Institute (Sanya), Chinese Academy of Agricultural Sciences, Sanya 572024, China. Electronic address: xialanqin@caas.cn.; State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing 100193, China. Electronic address: ningyuese@caas.cn.
Rice blast and bacterial blight, caused by the fungus Magnaporthe oryzae and the bacterium Xanthomonas oryzae pv. oryzae (Xoo), respectively, are devastating diseases affecting rice. Here, we report that a rice valine-glutamine (VQ) motif-containing protein, OsVQ25, balances broad-spectrum disease resistance and plant growth by interacting with a U-Box E3 ligase, OsPUB73, and a transcription factor, OsWRKY53. We show that OsPUB73 positively regulates rice resistance against M. oryzae and Xoo by interacting with and promoting OsVQ25 degradation via the 26S proteasome pathway. Knockout mutants of OsVQ25 exhibit enhanced resistance to both pathogens without a growth penalty. Furthermore, OsVQ25 interacts with and suppresses the transcriptional activity of OsWRKY53, a positive regulator of plant immunity. OsWRKY53 downstream defense-related genes and brassinosteroid signaling genes are upregulated in osvq25 mutants. Our findings reveal a ubiquitin E3 ligase-VQ protein-transcription factor module that fine-tunes plant immunity and growth at the transcriptional and posttranslational levels.
PMID: 35977497
Plant Physiol , IF:8.34 , 2022 Aug doi: 10.1093/plphys/kiac374
Identification of growth regulators using cross-species network analysis in plants.
Department of Plant Biotechnology and Bioinformatics, Ghent University, Technologiepark 71, 9052 Ghent, Belgium.; VIB Center for Plant Systems Biology, Technologiepark 71, 9052 Ghent, Belgium.; Institute of Biosciences and Bioresources, National Research Council (CNR), Via Amendola 165/A, 70126 Bari, Italy.; Umea Plant Science Centre (UPSC), Department of Plant Physiology, Umea University, 90187 Umea, Sweden.; SweTree Technologies AB, Skogsmarksgrand 7, SE-907 36 Umea, Sweden.; Faculty of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences, 1432 As, Norway.; Umea Plant Science Centre (UPSC), Department of Forest Genetics and Plant Physiology, Swedish University of Agricultural Sciences, 90183 Umea, Sweden.; Bioinformatics Institute Ghent, Ghent University, Technologiepark 71, 9052 Ghent, Belgium.
With the need to increase plant productivity, one of the challenges plant scientists are facing is to identify genes that play a role in beneficial plant traits. Moreover, even when such genes are found, it is generally not trivial to transfer this knowledge about gene function across species to identify functional orthologs. Here, we focused on the leaf to study plant growth. First, we built leaf growth transcriptional networks in Arabidopsis (Arabidopsis thaliana), maize (Zea mays), and aspen (Populus tremula). Next, known growth regulators, here defined as genes that when mutated or ectopically expressed alter plant growth, together with cross-species conserved networks, were used as guides to predict novel Arabidopsis growth regulators. Using an in-depth literature screening, 34 out of 100 top predicted growth regulators were confirmed to affect leaf phenotype when mutated or overexpressed and thus represent novel potential growth regulators. Globally, these growth regulators were involved in cell cycle, plant defense responses, gibberellin, auxin, and brassinosteroid signaling. Phenotypic characterization of loss-of-function lines confirmed two predicted growth regulators to be involved in leaf growth (NPF6.4 and LATE MERISTEM IDENTITY2). In conclusion, the presented network approach offers an integrative cross-species strategy to identify genes involved in plant growth and development.
PMID: 35984294
Plant Physiol , IF:8.34 , 2022 Jul doi: 10.1093/plphys/kiac354
DIACYLGLYCEROL KINASE 5 Participates in Flagellin-Induced Signaling in Arabidopsis.
Institute of Experimental Botany of the Czech Academy of Sciences, Rozvojova 263, 16502 Prague, Czech Republic.; Department of Experimental Plant Biology, Charles University, Vinicna 5, Prague 12844, Czech Republic.; Institute of Plant Sciences Paris Saclay IPS2, CNRS, INRA, Universite Paris-Sud, Universite Evry, Universite Paris-Saclay, Batiment 630, 91405 Orsay, France.; Institute of Plant Sciences Paris-Saclay IPS2, Paris Diderot, Sorbonne Paris-Cite, Batiment 630, 91405, Orsay, France.; Sorbonne Universite, Physiologie Cellulaire et Moleculaire des Plantes, F-75005 Paris, France.; Universite de Technologie de Compiegne, CNRS Enzyme and Cell Engineering Laboratory, Rue du Docteur Schweitzer, 60203 Compiegne, France.
Flagellin perception is a keystone of pattern-triggered immunity in plants. The recognition of this protein by a plasma membrane receptor complex is the beginning of a signaling cascade that includes protein phosphorylation and the production of reactive oxygen species (ROS). In both Arabidopsis (Arabidopsis thaliana) seedlings and suspension cells, we found that treatment with flg22, a peptide corresponding to the most conserved domain of bacterial flagellin, caused a rapid and transient decrease in the level of phosphatidylinositol 4,5-bisphosphate along with a parallel increase in phosphatidic acid (PA). In suspension cells, inhibitors of either phosphoinositide-dependent phospholipases C (PLC) or diacylglycerol kinases (DGKs) inhibited flg22-triggered PA production and the oxidative burst. In response to flg22, receptor-like kinase-deficient fls2, bak1 and bik1 mutants (FLAGELLIN SENSITIVE 2, BRASSINOSTEROID INSENSITIVE 1-associated kinase 1 and BOTRYTIS-INDUCED KINASE 1, respectively) produced less PA than wild-type (WT) plants, whereas this response did not differ in NADPH oxidase-deficient rbohD (RESPIRATORY BURST OXIDASE HOMOLOG D) plants. Among the DGK-deficient lines tested, the dgk5.1 mutant produced less PA and less ROS after flg22 treatment compared to WT seedlings. In response to flg22, dgk5.1 plants showed lower callose accumulation and impaired resistance to Pseudomonas syringae pv. tomato DC3000 hrcC-. Transcriptomics revealed that the basal expression of defense-related genes was altered in dgk5.1 seedlings compared to the WT. A GFP-DGK5 fusion protein localized to the plasma membrane, where RBOHD and PLC2 (proteins involved in plant immunity) are also located. The role of DGK5 and its enzymatic activity in flagellin signaling and fine-tuning of early immune responses in plant-microbe interactions is discussed.
PMID: 35900211
Plant Physiol , IF:8.34 , 2022 Jul doi: 10.1093/plphys/kiac332
Class I TCP transcription factor AtTCP8 modulates key brassinosteroid-responsive genes.
Department of Biological Sciences, Butler University, Indianapolis, Indiana, United States of America.; Division of Plant Sciences, University of Missouri, Columbia, Missouri, United States of America.; Christopher S. Bond Life Sciences Center and Interdisciplinary Plant Group, University of Missouri, Columbia, Missouri, United States of America.; Department of Biology, Marian University, Indianapolis, Indiana, United States of America.
The plant-specific TEOSINTE BRANCHED1/CYCLOIDEA/PROLIFERATING CELL FACTOR (TCP) transcription factor family is most closely associated with regulating plant developmental programs. Recently, TCPs were also shown to mediate host immune signaling, both as targets of pathogen virulence factors and as regulators of plant defense genes. However, comprehensive characterization of TCP gene targets is still lacking. Loss of function of the class I TCP gene AtTCP8 attenuates early immune signaling and, when combined with mutations in AtTCP14 and AtTCP15, additional layers of defense signaling in Arabidopsis (Arabidopsis thaliana). Here, we focus on TCP8, the most poorly characterized of the three to date. We used chromatin immunoprecipitation and RNA-sequencing to identify TCP8-bound gene promoters and differentially regulated genes in the tcp8 mutant; these data sets were heavily enriched in signaling components for multiple phytohormone pathways, including brassinosteroids (BRs), auxin, and jasmonic acid. Using BR signaling as a representative example, we showed that TCP8 directly binds and activates the promoters of the key BR transcriptional regulatory genes BRASSINAZOLE-RESISTANT1 (BZR1) and BRASSINAZOLE-RESISTANT2 (BZR2/BES1). Furthermore, tcp8 mutant seedlings exhibited altered BR-responsive growth patterns and complementary reductions in BZR2 transcript levels, while TCP8 protein demonstrated BR-responsive changes in subnuclear localization and transcriptional activity. We conclude that one explanation for the substantial targeting of TCP8 alongside other TCP family members by pathogen effectors may lie in its role as a modulator of BR and other plant hormone signaling pathways.
PMID: 35866682
Plant Physiol , IF:8.34 , 2022 Jul doi: 10.1093/plphys/kiac327
Brassinosteroid signaling restricts root lignification by antagonizing SHORT-ROOT function in Arabidopsis.
College of Life Science&College of Horticulture, Fujian Agriculture and Forestry University, Fuzhou 350002, China.; Ministry of Education Key Laboratory of Molecular and Cellular Biology, Hebei Collaboration Innovation Center for Cell Signaling, Hebei Key Laboratory of Molecular and Cellular Biology, College of Life Sciences, Hebei Normal University, Shijiazhuang, China.; Key Laboratory of Plant Development and Environment Adaptation Biology, Ministry of Education, School of Life Sciences, Shandong University, Jinan, China.
Cell wall lignification is a key step in forming functional endodermis and protoxylem in plant roots. Lignified casparian strips (CS) in endodermis and tracheary elements of protoxylem are essential for selective absorption and transport of water and nutrients. Although multiple key regulators of CS and protoxylem have been identified, the spatial information that drives the developmental shift to root lignification remains unknown. Here, we found that brassinosteroid signaling plays a key role in inhibiting root lignification in the root elongation zone. The inhibitory activity of brassinosteroid signaling occurs partially through the direct binding of BRASSINAZOLE-RESISTANT 1 (BZR1) to SHORT-ROOT (SHR), repressing the SHR-mediated activation of downstream genes that are involved in root lignification. Upon entering the mature root zone, brassinosteroid signaling declines rapidly, which releases SHR activity and initiates root lignification. Our results provide a mechanistic view of the developmental transition to cell wall lignification in Arabidopsis thaliana roots.
PMID: 35809074
Plant Physiol , IF:8.34 , 2022 Aug , V189 (4) : P2227-2243 doi: 10.1093/plphys/kiac237
Receptor-like protein kinase BAK1 promotes K+ uptake by regulating H+-ATPase AHA2 under low potassium stress.
State Key Laboratory of Plant Physiology and Biochemistry (SKLPPB), College of Biological Sciences, China Agricultural University, Beijing 100193, China.; School of Life Sciences, Institute of Life Science and Green Development, Hebei University, Baoding, Hebei 071002, China.
Potassium (K+) is one of the essential macronutrients for plant growth and development. However, the available K+ concentration in soil is relatively low. Plant roots can perceive low K+ (LK) stress, then enhance high-affinity K+ uptake by activating H+-ATPases in root cells, but the mechanisms are still unclear. Here, we identified the receptor-like protein kinase Brassinosteroid Insensitive 1-Associated Receptor Kinase 1 (BAK1) that is involved in LK response by regulating the Arabidopsis (Arabidopsis thaliana) plasma membrane H+-ATPase isoform 2 (AHA2). The bak1 mutant showed leaf chlorosis phenotype and reduced K+ content under LK conditions, which was due to the decline of K+ uptake capacity. BAK1 could directly interact with the AHA2 C terminus and phosphorylate T858 and T881, by which the H+ pump activity of AHA2 was enhanced. The bak1 aha2 double mutant also displayed a leaf chlorosis phenotype that was similar to their single mutants. The constitutively activated form AHA2Delta98 and phosphorylation-mimic form AHA2T858D or AHA2T881D could complement the LK sensitive phenotypes of both aha2 and bak1 mutants. Together, our data demonstrate that BAK1 phosphorylates AHA2 and enhances its activity, which subsequently promotes K+ uptake under LK conditions.
PMID: 35604103
Plant Physiol , IF:8.34 , 2022 Aug , V189 (4) : P2454-2466 doi: 10.1093/plphys/kiac194
SAUR15 interaction with BRI1 activates plasma membrane H+-ATPase to promote organ development of Arabidopsis.
State Key Laboratory of Grassland Agro-ecosystems; Key Laboratory of Grassland Livestock Industry Innovation, Ministry of Agriculture and Rural Affairs; College of Pastoral Agriculture Science and Technology, Lanzhou University, Lanzhou 730000, People's Republic of China.; Department of Biology, Institute of Biochemistry, Carleton University, Ottawa, Ontario K1S 5B6, Canada.; Ministry of Education Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou 730000, People's Republic of China.; School of Life Sciences, Guangzhou University, Guangzhou 510006, People's Republic of China.
Brassinosteroids (BRs) are an important group of plant steroid hormones that regulate growth and development. Several members of the SMALL AUXIN UP RNA (SAUR) family have roles in BR-regulated hypocotyl elongation and root growth. However, the mechanisms are unclear. Here, we show in Arabidopsis (Arabidopsis thaliana) that SAUR15 interacts with cell surface receptor-like kinase BRASSINOSTEROID-INSENSITIVE 1 (BRI1) in BR-treated plants, resulting in enhanced BRI1 phosphorylation status and recruitment of the co-receptor BRI1-ASSOCIATED RECEPTOR KINASE 1. Genetic and phenotypic assays indicated that the SAUR15 effect on BRI1 can be uncoupled from BRASSINOSTEROID INSENSITIVE 2 activity. Instead, we show that SAUR15 promotes BRI1 direct activation of plasma membrane H+-ATPase (PM H+-ATPase) via phosphorylation. Consequently, SAUR15-BRI1-PM H+-ATPase acts as a direct, PM-based mode of BR signaling that drives cell expansion to promote the growth and development of various organs. These data define an alternate mode of BR signaling in plants.
PMID: 35511168
J Integr Plant Biol , IF:7.061 , 2022 Jul doi: 10.1111/jipb.13327
The RECEPTOR-LIKE PROTEIN53 immune complex associates with LLG1 to positively regulate plant immunity.
State Key Laboratory of Ecological Control of Fujian-Taiwan Crop Pests, Key Laboratory of Ministry of Education for Genetics, Breeding and Multiple Utilization of Crops, Plant Immunity Center, Fujian Agriculture and Forestry University, Fuzhou, 350002, China.; Institute of Genetics and Developmental Biology, the Chinese Academy of Sciences, Beijing, 100101, China.; College of Life Sciences, University of Chinese Academy of Sciences, Beijing, 100049, China.; Ministerial and Provincial Joint Innovation Centre for Safety Production of Cross-Strait Crops, Fujian Agriculture and Forestry University, Fuzhou, 350002, China.
Pattern recognition receptors (PRRs) sense ligands in pattern-triggered immunity (PTI). Plant PRRs include numerous receptor-like proteins (RLPs), but many RLPs remain functionally uncharacterized. Here, we examine an Arabidopsis thaliana RLP, RLP53, which positively regulates immune signaling. Our forward genetic screen for suppressors of enhanced disease resistance1 (edr1) identified a point mutation in RLP53 that fully suppresses disease resistance and mildew-induced cell death in edr1 mutants. The rlp53 mutants showed enhanced susceptibility to virulent pathogens, including fungi, oomycetes, and bacteria, indicating that RLP53 is important for plant immunity. The ectodomain of RLP53 contains leucine-rich repeat (LRR) motifs. RLP53 constitutively associates with the LRR receptor-like kinase SUPPRESSOR OF BRASSINOSTEROID INSENSITIVE1-ASSOCIATED KINASE (BAK1)-INTERACTING RECEPTOR KINASE1 (SOBIR1) and interacts with the co-receptor BAK1 in a pathogen-induced manner. The double mutation sobir1-12 bak1-5 suppresses edr1-mediated disease resistance, suggesting that EDR1 negatively regulates PTI modulated by the RLP53-SOBIR1-BAK1 complex. Moreover, the glycosylphosphatidylinositol (GPI)-anchored protein LORELEI-LIKE GPI-ANCHORED PROTEIN1 (LLG1) interacts with RLP53 and mediates RLP53 accumulation in the plasma membrane. We thus uncovered the role of a novel RLP and its associated immune complex in plant defense responses and revealed a potential new mechanism underlying regulation of RLP immune function by a GPI-anchored protein.
PMID: 35796320
J Integr Plant Biol , IF:7.061 , 2022 Aug , V64 (8) : P1614-1630 doi: 10.1111/jipb.13322
The divergence of brassinosteroid sensitivity between rice subspecies involves natural variation conferring altered internal auto-binding of OsBSK2.
National Key Facility for Crop Gene Resources and Genetic Improvement, Institute of Crop Sciences, Chinese Academy of Agricultural Sciences, Beijing, 100081, China.; Rice Research Institute of Anhui Academy of Agricultural Sciences, Hefei, 230001, China.; State Key Laboratory of Plant Genomics, Institute of Genetics and Developmental Biology, the Innovative Academy for Seed Design, Chinese Academy of Sciences, Beijing, 100101, China.
Japonica/geng and indica/xian are two major rice (Oryza sativa) subspecies with multiple divergent traits, but how these traits are related and interact within each subspecies remains elusive. Brassinosteroids (BRs) are a class of steroid phytohormones that modulate many important agronomic traits in rice. Here, using different physiological assays, we revealed that japonica rice exhibits an overall lower BR sensitivity than indica. Extensive screening of BR signaling genes led to the identification of a set of genes distributed throughout the primary BR signaling pathway with divergent polymorphisms. Among these, we demonstrate that the C38/T variant in BR Signaling Kinase2 (OsBSK2), causing the amino acid change P13L, plays a central role in mediating differential BR signaling in japonica and indica rice. OsBSK2(L13) in indica plays a greater role in BR signaling than OsBSK2(P13) in japonica by affecting the auto-binding and protein accumulation of OsBSK2. Finally, we determined that OsBSK2 is involved in a number of divergent traits in japonica relative to indica rice, including grain shape, tiller number, cold adaptation, and nitrogen-use efficiency. Our study suggests that the natural variation in OsBSK2 plays a key role in the divergence of BR signaling, which underlies multiple divergent traits between japonica and indica.
PMID: 35766344
J Integr Plant Biol , IF:7.061 , 2022 Aug , V64 (8) : P1560-1574 doi: 10.1111/jipb.13311
OsCPL3 is involved in brassinosteroid signaling by regulating OsGSK2 stability.
State Key Laboratory of Hybrid Rice, Department of Plant Sciences, College of Life Sciences, Wuhan University, Wuhan, 430072, China.; State Key Laboratory of Plant Genomics, Institute of Genetics and Developmental Biology, the Innovative Academy for Seed Design, Chinese Academy of Sciences, Beijing, 100101, China.; Hubei Hongshan Laboratory, Wuhan, 430070, China.
Glycogen synthase kinase 3 (GSK3) proteins play key roles in brassinosteroid (BR) signaling during plant growth and development by phosphorylating various substrates. However, how GSK3 protein stability and activity are themselves modulated is not well understood. Here, we demonstrate in vitro and in vivo that C-TERMINAL DOMAIN PHOSPHATASE-LIKE 3 (OsCPL3), a member of the RNA Pol II CTD phosphatase-like family, physically interacts with OsGSK2 in rice (Oryza sativa). OsCPL3 expression was widely detected in various tissues and organs including roots, leaves and lamina joints, and was induced by exogenous BR treatment. OsCPL3 localized to the nucleus, where it dephosphorylated OsGSK2 at the Ser-222 and Thr-284 residues to modulate its protein turnover and kinase activity, in turn affecting the degradation of BRASSINAZOLE-RESISTANT 1 (BZR1) and BR signaling. Loss of OsCPL3 function resulted in higher OsGSK2 abundance and lower OsBZR1 levels, leading to decreased BR responsiveness and alterations in plant morphology including semi-dwarfism, leaf erectness and grain size, which are of fundamental importance to crop productivity. These results reveal a previously unrecognized role for OsCPL3 and add another layer of complexity to the tightly controlled BR signaling pathway in plants.
PMID: 35665602
Plant J , IF:6.417 , 2022 Aug , V111 (3) : P785-799 doi: 10.1111/tpj.15852
GhBZR3 suppresses cotton fiber elongation by inhibiting very-long-chain fatty acid biosynthesis.
Key Laboratory of Plant Molecular Physiology, Institute of Botany, Chinese Academy of Sciences, Beijing, 100093, China.; College of Life Science, University of Chinese Academy of Sciences, Beijing, 100049, China.; School of Food and Biological Engineering, Shaanxi University of Science and Technology, Xi'an, 710021, China.; School of Ecology and Environment, Northwestern Polytechnical University, Xi'an, 710012, China.; College of Life Sciences, Shaanxi Normal University, Xi'an, 710062, China.
The BRASSINAZOLE-RESISTANT (BZR) transcription factor is a core component of brassinosteroid (BR) signaling and is involved in the development of many plant species. BR is essential for the initiation and elongation of cotton fibers. However, the mechanism of BR-regulating fiber development and the function of BZR is poorly understood in Gossypium hirsutum L. (cotton). Here, we identified a BZR family transcription factor protein referred to as GhBZR3 in cotton. Overexpression of GhBZR3 in Arabidopsis caused shorter root hair length, hypocotyl length, and hypocotyl cell length, indicating that GhBZR3 negatively regulates cell elongation. Pathway enrichment analysis from VIGS-GhBZR3 cotton plants found that fatty acid metabolism and degradation might be the regulatory pathway that is primarily controlled by GhBZR3. Silencing GhBZR3 expression in cotton resulted in taller plant height as well as longer fibers. The very-long-chain fatty acid (VLCFA) content was also significantly increased in silenced GhBZR3 plants compared with the wild type. The GhKCS13 promoter, a key gene for VLCFA biosynthesis, contains two GhBZR3 binding sites. The results of yeast one-hybrid, electrophoretic mobility shift, and luciferase assays revealed that GhBZR3 directly interacted with the GhKCS13 promoter to suppress gene expression. Taken together, these results indicate that GhBZR3 negatively regulates cotton fiber development by reducing VLCFA biosynthesis. This study not only deepens our understanding of GhBZR3 function in cotton fiber development, but also highlights the potential of improving cotton fiber length and plant growth using GhBZR3 and its related genes in future cotton breeding programs.
PMID: 35653239
Int J Mol Sci , IF:5.923 , 2022 Aug , V23 (16) doi: 10.3390/ijms23169500
Expression of a Hydroxycinnamoyl-CoA Shikimate/Quinate Hydroxycinnamoyl Transferase 4 Gene from Zoysia japonica (ZjHCT4) Causes Excessive Elongation and Lignin Composition Changes in Agrostis stolonifera.
School of Grassland Science, Beijing Forestry University, Beijing 100083, China.; School of Biological and Food Engineering, Suzhou University, Suzhou 234000, China.; Inner Mongolia M-Grass Ecology and Environment (Group) Co., Ltd., Hohhot 010000, China.
Hydroxycinnamoyl-CoA shikimate/quinate hydroxycinnamoyl transferase (HCT) is considered to be an essential enzyme for regulating the biosynthesis and composition of lignin. To investigate the properties and function of ZjHCT4, the ZjHCT4 gene was cloned from Zoysia japonica with a completed coding sequence of 1284-bp in length, encoding 428 amino acids. The ZjHCT4 gene promoter has several methyl jasmonate (MeJA) response elements. According to analysis of expression patterns, it was up-regulated by MeJA, GA3 (Gibberellin), and SA (Salicylic acid), and down-regulated by ABA (Abscisic acid). Ectopic ZjHCT4 expression in creeping bentgrass causes excessive plant elongation. In addition, the content of G-lingnin and H-lingnin fell in transgenic plants, whereas the level of S-lingnin increased, resulting in a considerable rise in the S/G unit ratio. Analysis of the expression levels of lignin-related genes revealed that the ectopic expression of ZjHCT4 altered the expression levels of a number of genes involved in the lignin synthesis pathway. Simultaneously, MeJA, SA, GA3, IAA, BR (Brassinosteroid), and other hormones were dramatically enhanced in transgenic plants relative to control plants, whereas ABA concentration was significantly decreased. Expression of ZjHCT4 impacted lignin composition and plant growth via altering the phenylpropionic acid metabolic pathway and hormone response, as revealed by transcriptome analysis. HCTs may influence plant lignin composition and plant development by altering hormone content. These findings contributed to a deeper comprehension of the lignin synthesis pathway and set the stage for further investigation and application of the HCTs gene.
PMID: 36012757
Int J Mol Sci , IF:5.923 , 2022 Jul , V23 (14) doi: 10.3390/ijms23147915
Impact of Exogenous Application of Potato Virus Y-Specific dsRNA on RNA Interference, Pattern-Triggered Immunity and Poly(ADP-ribose) Metabolism.
Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry of the Russian Academy of Sciences, 117997 Moscow, Russia.; Doka-Gene Technologies Ltd., 141880 Rogachevo, Russia.; The James Hutton Institute, Invergowrie, Dundee DD2 5DA, UK.; Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, 119991 Moscow, Russia.
In this work we developed and exploited a spray-induced gene silencing (SIGS)-based approach to deliver double-stranded RNA (dsRNA), which was found to protect potato against potato virus Y (PVY) infection. Given that dsRNA can act as a defence-inducing signal that can trigger sequence-specific RNA interference (RNAi) and non-specific pattern-triggered immunity (PTI), we suspected that these two pathways may be invoked via exogeneous application of dsRNA, which may account for the alterations in PVY susceptibility in dsRNA-treated potato plants. Therefore, we tested the impact of exogenously applied PVY-derived dsRNA on both these layers of defence (RNAi and PTI) and explored its effect on accumulation of a homologous virus (PVY) and an unrelated virus (potato virus X, PVX). Here, we show that application of PVY dsRNA in potato plants induced accumulation of both small interfering RNAs (siRNAs), a hallmark of RNAi, and some PTI-related gene transcripts such as WRKY29 (WRKY transcription factor 29; molecular marker of PTI), RbohD (respiratory burst oxidase homolog D), EDS5 (enhanced disease susceptibility 5), SERK3 (somatic embryogenesis receptor kinase 3) encoding brassinosteroid-insensitive 1-associated receptor kinase 1 (BAK1), and PR-1b (pathogenesis-related gene 1b). With respect to virus infections, PVY dsRNA suppressed only PVY replication but did not exhibit any effect on PVX infection in spite of the induction of PTI-like effects in the presence of PVX. Given that RNAi-mediated antiviral immunity acts as the major virus resistance mechanism in plants, it can be suggested that dsRNA-based PTI alone may not be strong enough to suppress virus infection. In addition to RNAi- and PTI-inducing activities, we also showed that PVY-specific dsRNA is able to upregulate production of a key enzyme involved in poly(ADP-ribose) metabolism, namely poly(ADP-ribose) glycohydrolase (PARG), which is regarded as a positive regulator of biotic stress responses. These findings offer insights for future development of innovative approaches which could integrate dsRNA-induced RNAi, PTI and modulation of poly(ADP-ribose) metabolism in a co-ordinated manner, to ensure a high level of crop protection.
PMID: 35887257
Front Plant Sci , IF:5.753 , 2022 , V13 : P945379 doi: 10.3389/fpls.2022.945379
Integrative analysis of transcriptome and miRNAome reveals molecular mechanisms regulating pericarp thickness in sweet corn during kernel development.
Guangdong Provincial Key Laboratory of Plant Molecular Breeding, College of Agriculture, South China Agricultural University, Guangzhou, China.
Pericarp thickness affects the edible quality of sweet corn (Zea mays L. saccharata Sturt.). Therefore, breeding varieties with a thin pericarp is important for the quality breeding of sweet corn. However, the molecular mechanisms underlying the pericarp development remain largely unclear. We performed an integrative analysis of mRNA and miRNA sequencing to elucidate the genetic mechanism regulating pericarp thickness during kernel development (at 15 days, 19 days, and 23 days after pollination) of two sweet corn inbred lines with different pericarp thicknesses (M03, with a thinner pericarp and M08, with a thicker pericarp). A total of 2,443 and 1,409 differentially expressed genes (DEGs) were identified in M03 and M08, respectively. Our results indicate that phytohormone-mediated programmed cell death (PCD) may play a critical role in determining pericarp thickness in sweet corn. Auxin (AUX), gibberellin (GA), and brassinosteroid (BR) signal transduction may indirectly mediate PCD to regulate pericarp thickness in M03 (the thin pericarp variety). In contrast, abscisic acid (ABA), cytokinin (CK), and ethylene (ETH) signaling may be the key regulators of pericarp PCD in M08 (the thick pericarp variety). Furthermore, 110 differentially expressed microRNAs (DEMIs) and 478 differentially expressed target genes were identified. miRNA164-, miRNA167-, and miRNA156-mediated miRNA-mRNA pairs may participate in regulating pericarp thickness. The expression results of DEGs were validated by quantitative real-time PCR. These findings provide insights into the molecular mechanisms regulating pericarp thickness and propose the objective of breeding sweet corn varieties with a thin pericarp.
PMID: 35958194
Front Plant Sci , IF:5.753 , 2022 , V13 : P938339 doi: 10.3389/fpls.2022.938339
Quantitative Trait Loci Mapping Analysis for Cold Tolerance Under Cold Stress and Brassinosteroid-Combined Cold Treatment at Germination and Bud Burst Stages in Rice.
Key Laboratory of Agricultural Biotechnology of Liaoning Province, College of Biosciences and Biotechnology, Shenyang Agricultural University, Shenyang, China.; Rice Research Institute, College of Agronomy, Shenyang Agricultural University, Shenyang, China.; Rice Research Institute, Jiangxi Academy of Agricultural Sciences, Nanchang, China.; Department of Agronomy, College of Agriculture, Purdue University, West Lafayette, IN, United States.
Low temperature is one of the major abiotic stresses limiting seed germination and early seedling growth in rice. Brassinosteroid (BR) application can improve cold tolerance in rice. However, the regulatory relationship between cold tolerance and BR in rice remains undefined. Here, we constructed a population of 140 backcross recombinant inbred lines (BRILs) derived from a cross between a wild rice (Dongxiang wild rice, DXWR) and a super rice (SN265). The low-temperature germination rate (LTG), survival rate (SR), plant height (PH), and first leaf length (FLL) were used as indices for assessing cold tolerance under cold stress and BR-combined cold treatment at seed germination and bud burst stages. A high-resolution SNP genetic map, covering 1,145 bin markers with a distance of 3188.33 cM onto 12 chromosomes, was constructed using the GBS technique. A total of 73 QTLs were detected, of which 49 QTLs were identified under cold stress and 24 QTLs under BR-combined cold treatment. Among these, intervals of 30 QTLs were pairwise coincident under cold stress and BR-combined cold treatment, as well as different traits including SR and FLL, and PH and FLL, respectively. A total of 14 candidate genes related to cold tolerance or the BR signaling pathway, such as CBF/DREB (LOC_Os08g43200), bHLH (LOC_Os07g08440 and LOC_Os07g08440), WRKY (LOC_Os06g30860), MYB (LOC_Os01g62410 and LOC_Os05g51160), and BRI1-associated receptor kinase 1 precursor (LOC_Os06g16300), were located. Among these, the transcript levels of 10 candidate genes were identified under cold stress and BR-combined cold treatment by qRT-PCR. These findings provided an important basis for further mining the genes related to cold tolerance or the BR signaling pathway and understanding the molecular mechanisms of cold tolerance in rice.
PMID: 35923884
Front Plant Sci , IF:5.753 , 2022 , V13 : P930805 doi: 10.3389/fpls.2022.930805
SlCESTA Is a Brassinosteroid-Regulated bHLH Transcription Factor of Tomato That Promotes Chilling Tolerance and Fruit Growth When Over-Expressed.
Biotechnology of Horticultural Crops, TUM School of Life Sciences, Technical University of Munich, Freising, Germany.; Institute of Plant Biology, Technical University of Braunschweig, Braunschweig, Germany.; Plant Growth Regulation, TUM School of Life Sciences, Technical University of Munich, Freising, Germany.
Brassinosteroids (BRs) are required for various aspects of plant growth and development, but also participate in stress responses. The hormones convey their activity through transcriptional regulation and posttranslational modification of transcription factors and one class are basic helix-loop-helix (bHLH) proteins of the BR Enhanced Expression (BEE) subfamily, which in Arabidopsis thaliana include BEE1-3 and CESTA (CES). CES and the BEEs promote the expression of different BR-responsive genes, including genes encoding gibberellin (GA) biosynthetic and catabolizing enzymes, as well as cold-responsive genes. Interestingly, in terms of an application, CES could promote both fruit growth and cold stress tolerance when over-expressed in A. thaliana and here it was investigated, if this function is conserved in the fruit crop Solanum lycopersicum (cultivated tomato). Based on amino acid sequence similarity and the presence of regulatory motifs, a CES orthologue of S. lycopersicum, SlCES, was identified and the effects of its over-expression were analysed in tomato. This showed that SlCES, like AtCES, was re-localized to nuclear bodies in response to BR signaling activation and that it effected GA homeostasis, with related phenotypes, when over-expressed. In addition, over-expression lines showed an increased chilling tolerance and had altered fruit characteristics. The possibilities and potential limitations of a gain of SlCES function as a breeding strategy for tomato are discussed.
PMID: 35909777
Front Plant Sci , IF:5.753 , 2022 , V13 : P939487 doi: 10.3389/fpls.2022.939487
Glycogen synthase kinases in model and crop plants - From negative regulators of brassinosteroid signaling to multifaceted hubs of various signaling pathways and modulators of plant reproduction and yield.
Faculty of Natural Sciences, Institute of Biology, Biotechnology and Environmental Protection, University of Silesia, Katowice, Poland.
Glycogen synthase kinases, also known as SHAGGY-like Kinases (GSKs/SKs), are highly conserved serine/threonine protein kinases present both in animals and plants. Plant genomes contain multiple homologs of the GSK3 genes which participate in various biological processes. Plant GSKs/SKs, and their best known representative in Arabidopsis thaliana - Brassinosteroid Insentisive2 (BIN2/SK21) in particular, were first identified as components of the brassinosteroid (BR) signaling pathway. As phytohormones, BRs regulate a wide range of physiological processes in plants - from germination, cell division, elongation and differentiation to leaf senescence, and response to environmental stresses. The GSKs/SKs proteins belong to a group of several highly conserved components of the BR signaling which evolved early during evolution of this molecular relay. However, recent reports indicated that the GSKs/SKs proteins are also implicated in signaling pathways of other phytohormones and stress-response processes. As a consequence, the GSKs/SKs proteins became hubs of various signaling pathways and modulators of plant development and reproduction. Thus, it is very important to understand molecular mechanisms regulating activity of the GSKs/SKs proteins, but also to get insights into role of the GSKs/SKs proteins in modulation of stability and activity of various substrate proteins which participate in the numerous signaling pathways. Although elucidation of these aspects is still in progress, this review presents a comprehensive and detailed description of these processes and their implications for regulation of development, stress response, and reproduction of model and crop species. The GSKs/SKs proteins and their activity are modulated through phosphorylation and de-phosphorylation reactions which are regulated by various proteins. Importantly, both phosphorylations and de-phosphorylations may have positive and negative effects on the activity of the GSKs/SKs proteins. Additionally, the activity of the GSKs/SKs proteins is positively regulated by reactive oxygen species, whereas it is negatively regulated through ubiquitylation, deacetylation, and nitric oxide-mediated nitrosylation. On the other hand, the GSKs/SKs proteins interact with proteins representing various signaling pathways, and on the basis of the complicated network of interactions the GSKs/SKs proteins differentially regulate various physiological, developmental, stress response, and yield-related processes.
PMID: 35909730
Front Plant Sci , IF:5.753 , 2022 , V13 : P952246 doi: 10.3389/fpls.2022.952246
A Predominant Role of AtEDEM1 in Catalyzing a Rate-Limiting Demannosylation Step of an Arabidopsis Endoplasmic Reticulum-Associated Degradation Process.
State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, South China Agricultural University, Guangzhou, China.; Guangdong Key Laboratory for Innovative Development and Utilization of Forest Plant Germplasm, College of Forestry and Landscape Architecture, South China Agricultural University, Guangzhou, China.; Department of Molecular, Cellular, and Developmental Biology, University of Michigan, Ann Arbor, MI, United States.; University of Chinese Academy of Sciences, Beijing, China.; The Center of Excellence for Molecular Plant Sciences, Chinese Academy of Sciences, Shanghai, China.; Glycomics and Glycan Bioengineering Research Center, College of Food Science and Technology, Nanjing Agricultural University, Nanjing, China.
Endoplasmic reticulum-associated degradation (ERAD) is a key cellular process for degrading misfolded proteins. It was well known that an asparagine (N)-linked glycan containing a free alpha1,6-mannose residue is a critical ERAD signal created by Homologous to alpha-mannosidase 1 (Htm1) in yeast and ER-Degradation Enhancing alpha-Mannosidase-like proteins (EDEMs) in mammals. An earlier study suggested that two Arabidopsis homologs of Htm1/EDEMs function redundantly in generating such a conserved N-glycan signal. Here we report that the Arabidopsis irb1 (reversal of bri1) mutants accumulate brassinosteroid-insensitive 1-5 (bri1-5), an ER-retained mutant variant of the brassinosteroid receptor BRI1 and are defective in one of the Arabidopsis Htm1/EDEM homologs, AtEDEM1. We show that the wild-type AtEDEM1, but not its catalytically inactive mutant, rescues irb1-1. Importantly, an insertional mutation of the Arabidopsis Asparagine-Linked Glycosylation 3 (ALG3), which causes N-linked glycosylation with truncated glycans carrying a different free alpha1,6-mannose residue, completely nullifies the inhibitory effect of irb1-1 on bri1-5 ERAD. Interestingly, an insertional mutation in AtEDEM2, the other Htm1/EDEM homolog, has no detectable effect on bri1-5 ERAD; however, it enhances the inhibitory effect of irb1-1 on bri1-5 degradation. Moreover, AtEDEM2 transgenes rescued the irb1-1 mutation with lower efficacy than AtEDEM1. Simultaneous elimination of AtEDEM1 and AtEDEM2 completely blocks generation of alpha1,6-mannose-exposed N-glycans on bri1-5, while overexpression of either AtEDEM1 or AtEDEM2 stimulates bri1-5 ERAD and enhances the bri1-5 dwarfism. We concluded that, despite its functional redundancy with AtEDEM2, AtEDEM1 plays a predominant role in promoting bri1-5 degradation.
PMID: 35874007
Front Plant Sci , IF:5.753 , 2022 , V13 : P834027 doi: 10.3389/fpls.2022.834027
Identification and Characterization of Long Non-coding RNA in Tomato Roots Under Salt Stress.
Institute of Horticulture Crops, Xinjiang Academy of Agricultural Sciences, Urumqi, China.; Key Laboratory of Horticulture Crop Genomics and Genetic Improvement in Xinjiang, Urumqi, China.; Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Beijing, China.
As one of the most important vegetable crops in the world, the production of tomatoes was restricted by salt stress. Therefore, it is of great interest to analyze the salt stress tolerance genes. As the non-coding RNAs (ncRNAs) with a length of more than 200 nucleotides, long non-coding RNAs (lncRNAs) lack the ability of protein-coding, but they can play crucial roles in plant development and response to abiotic stresses by regulating gene expression. Nevertheless, there are few studies on the roles of salt-induced lncRNAs in tomatoes. Therefore, we selected wild tomato Solanum pennellii (S. pennellii) and cultivated tomato M82 to be materials. By high-throughput sequencing, 1,044 putative lncRNAs were identified here. Among them, 154 and 137 lncRNAs were differentially expressed in M82 and S. pennellii, respectively. Through functional analysis of target genes of differentially expressed lncRNAs (DE-lncRNAs), some genes were found to respond positively to salt stress by participating in abscisic acid (ABA) signaling pathway, brassinosteroid (BR) signaling pathway, ethylene (ETH) signaling pathway, and anti-oxidation process. We also construct a salt-induced lncRNA-mRNA co-expression network to dissect the putative mechanisms of high salt tolerance in S. pennellii. We analyze the function of salt-induced lncRNAs in tomato roots at the genome-wide levels for the first time. These results will contribute to understanding the molecular mechanisms of salt tolerance in tomatoes from the perspective of lncRNAs.
PMID: 35865296
Theor Appl Genet , IF:5.699 , 2022 Aug , V135 (8) : P2907-2923 doi: 10.1007/s00122-022-04158-0
The brassinosteroid biosynthesis gene TaD11-2A controls grain size and its elite haplotype improves wheat grain yields.
Key Laboratory of Molecular Module-Based Breeding of High Yield and Abiotic Resistant Plants in Universities of Shandong, College of Agriculture, Ludong University, Yantai, Shandong, China.; State Key Laboratory of Crop Biology, College of Agronomy, Shandong Agricultural University, Taian, Shandong, China.; Key Laboratory of Molecular Module-Based Breeding of High Yield and Abiotic Resistant Plants in Universities of Shandong, College of Agriculture, Ludong University, Yantai, Shandong, China. sdaucf@126.com.; Key Laboratory of Molecular Module-Based Breeding of High Yield and Abiotic Resistant Plants in Universities of Shandong, College of Agriculture, Ludong University, Yantai, Shandong, China. yongzhenwu1204@163.com.
KEY MESSAGE: TaD11-2A affects grain size and root length and its natural variations are associated with significant differences in yield-related traits in wheat. Brassinosteroids (BRs) control many important agronomic traits and therefore the manipulation of BR components could improve crop productivity and performance. However, the potential effects of BR-related genes on yield-related traits and stress tolerance in wheat (Triticum aestivum L.) remain poorly understood. Here, we identified TaD11 genes in wheat (rice D11 orthologs) that encoded enzymes involved in BR biosynthesis. TaD11 genes were highly expressed in roots (Zadoks scale: Z11) and grains (Z75), while expression was significantly suppressed by exogenous BR (24-epiBL). Ectopic expression of TaD11-2A rescued the abnormal panicle structure and plant height (PH) of the clustered primary branch 1 (cpb1) mutant, and also increased endogenous BR levels, resulting in improved grain yields and grain quality in rice. The tad11-2a-1 mutant displayed dwarfism, smaller grains, sensitivity to 24-epiBL, and reduced endogenous BR contents. Natural variations in TaD11-2A were associated with significant differences in yield-related traits, including PH, grain width, 1000-grain weight, and grain yield per plant, and its favorable haplotype, TaD11-2A-HapI was subjected to positive selection during wheat breeding. Additionally, TaD11-2A influenced root length and salt tolerance in rice and wheat at seedling stages. These results indicated the important role of BR TaD11 biosynthetic genes in controlling grain size and root length, and also highlighted their potential in the molecular biological analysis of wheat.
PMID: 35794218
Front Genet , IF:4.599 , 2022 , V13 : P932166 doi: 10.3389/fgene.2022.932166
Molecular mapping of QTLs for grain dimension traits in Basmati rice.
Division of Genetics, ICAR-Indian Agricultural Research Institute (ICAR-IARI), New Delhi, India.; Amity Institute of Biotechnology, Amity University, Noida, India.; Rice Breeding and Genetics Research Centre, ICAR-IARI, Aduthurai, India.; ICAR-National Institute for Plant Biotechnology, IARI, New Delhi, India.
Basmati rice is known for its extra-long slender grains, exceptional kernel dimensions after cooking, high volume expansion, and strong aroma. Developing high yielding Basmati rice varieties with good cooking quality is a gigantic task. Therefore, identifying the genomic regions governing the grain and cooked kernel dimension traits is of utmost importance for its use in marker-assisted breeding. Although several QTLs governing grain dimension traits have been reported, limited attempts have been made to map QTLs for grain and cooked kernel dimension traits of Basmati rice. In the current study, a population of recombinant inbred lines (RIL) was generated from a cross of Sonasal and Pusa Basmati 1121 (PB1121). In the RIL population, there was a significant positive correlation among the length (RRL: rough rice length, MRL: milled rice length, CKL: cooked kernel length) and breadth (RRB: rough rice breadth, MRB: milled rice breadth and CKB: cooked kernel breadth) of the related traits, while there was significant negative correlation between them. QTL mapping has led to the identification of four major genomic regions governing MRL and CKL. Two QTLs co-localize with the earlier reported major gene GS3 and a QTL qGRL7.1, while the remaining two QTLs viz., qCKL3.2 (qMRL3.2) and qCKL4.1 (qMRL4.1) were novel. The QTL qCKL3.2 has been bracketed to a genomic region of 0.78 Mb between the markers RM15247 and RM15281. Annotation of this region identified 18 gene models, of which the genes predicted to encode pentatricopeptides and brassinosteroid insensitive 1-associated receptor kinase 1 precursor may be the putative candidate genes. Furthermore, we identified a novel QTL qKER2.1 governing kernel elongation ratio (KER) in Basmati rice.
PMID: 35983411
Front Genet , IF:4.599 , 2022 , V13 : P953458 doi: 10.3389/fgene.2022.953458
In-Silico Study of Brassinosteroid Signaling Genes in Rice Provides Insight Into Mechanisms Which Regulate Their Expression.
Institute of Biology, Biotechnology and Environmental Protection, Faculty of Natural Sciences, University of Silesia, Katowice, Poland.
Brassinosteroids (BRs) regulate a diverse spectrum of processes during plant growth and development and modulate plant physiology in response to environmental fluctuations and stress factors. Thus, the BR signaling regulators have the potential to be targeted for gene editing to optimize the architecture of plants and make them more resilient to environmental stress. Our understanding of the BR signaling mechanism in monocot crop species is limited compared to our knowledge of this process accumulated in the model dicot species - Arabidopsis thaliana. A deeper understanding of the BR signaling and response during plant growth and adaptation to continually changing environmental conditions will provide insight into mechanisms that govern the coordinated expression of the BR signaling genes in rice (Oryza sativa) which is a model for cereal crops. Therefore, in this study a comprehensive and detailed in silico analysis of promoter sequences of rice BR signaling genes was performed. Moreover, expression profiles of these genes during various developmental stages and reactions to several stress conditions were analyzed. Additionally, a model of interactions between the encoded proteins was also established. The obtained results revealed that promoters of the 39 BR signaling genes are involved in various regulatory mechanisms and interdependent processes that influence growth, development, and stress response in rice. Different transcription factor-binding sites and cis-regulatory elements in the gene promoters were identified which are involved in regulation of the genes' expression during plant development and reactions to stress conditions. The in-silico analysis of BR signaling genes in O. sativa provides information about mechanisms which regulate the coordinated expression of these genes during rice development and in response to other phytohormones and environmental factors. Since rice is both an important crop and the model species for other cereals, this information may be important for understanding the regulatory mechanisms that modulate the BR signaling in monocot species. It can also provide new ways for the plant genetic engineering technology by providing novel potential targets, either cis-elements or transcriptional factors, to create elite genotypes with desirable traits.
PMID: 35873468
Physiol Plant , IF:4.5 , 2022 Aug : Pe13764 doi: 10.1111/ppl.13764
The putative obtusifoliol 14alpha-demethylase OsCYP51H3 affects multiple aspects of rice growth and development.
Guangdong Provincial Key Laboratory of Applied Botany & Key Laboratory of South China Agricultural Plant Molecular Analysis and Genetic Improvement, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou, China.; Center of Economic Botany, Core Botanical Gardens, Chinese Academy of Sciences, Guangzhou, China.; University of Chinese Academy of Sciences, Beijing, China.
Some members of the CYP51G subfamily has been shown to be obtusifoliol 14alpha-demethylase, key enzyme of the sterol and brassinosteroid (BR) biosynthesis, which mediate plant development and response to stresses. However, little is known about the functions of CYP51H subfamily in rice. Here, OsCYP51H3, an ortholog of rice OsCYP51G1 was identified. Compared with wild type, the mutants oscyp51H3 and OsCYP51H3-RNAi showed dwarf phenotype, late flowering, erected leaves, lower seed-setting rate and smaller and shorter seeds. In contrast, the phenotypic changes of OsCYP51H3-OE plants are not obvious. Metabolomic analysis of oscyp51H3 mutant indicated that OsCYP51H3 may also encode an obtusifoliol 14alpha-demethylase involved in phytosterol and BR biosynthesis, but possibly not that of triterpenes. The RNA-seq results showed that OsCYP51H3 may affect the expression of a lot of genes related to rice development. These findings showed that OsCYP51H3 codes for a putative obtusifoliol 14alpha-demethylase involved in phytosterol and BR biosynthesis, and mediates rice development.
PMID: 35975452
Sci Rep , IF:4.379 , 2022 Jul , V12 (1) : P11294 doi: 10.1038/s41598-022-15284-6
A brassinosteroid functional analogue increases soybean drought resilience.
Plant Breeding, Wageningen University and Research, 6708 PB, Wageningen, The Netherlands.; Instituto de Fisiologia y Recursos Geneticos Vegetales Victorio S. Trippi - Unidad de Estudios Agropecuarios (IFRGV-UDEA, INTA-CONICET), Av. 11 de septiembre 4755, CP X5014MGO, Cordoba, Argentina.; Instituto de Tecnologia Agroindustrial del Noroeste Argentino (ITANOA), Estacion Experimental Agroindustrial Obispo Colombres (EEAOC) /Consejo Nacional de Investigaciones Cientificas Y Tecnicas (CONICET), Las Talitas, Tucuman, Argentina.; Centro de Bioplantas, Universidad de Ciego de Avila "Maximo Gomez Baez", Ciego de Avila, Cuba.; Centro de Estudios de Productos Naturales, Facultad de Quimica, Universidad de La Habana, Havana, Cuba.; Instituto de Tecnologia Agroindustrial del Noroeste Argentino (ITANOA), Estacion Experimental Agroindustrial Obispo Colombres (EEAOC) /Consejo Nacional de Investigaciones Cientificas Y Tecnicas (CONICET), Las Talitas, Tucuman, Argentina. empardokarate@gmail.com.
Drought severely affects soybean productivity, challenging breeding/management strategies to increase crop resilience. Hormone-based biostimulants like brassinosteroids (BRs) modulate growth/defence trade-off, mitigating yield losses; yet, natural molecule's low stability challenges the development of cost-effective and long-lasting analogues. Here, we investigated for the first time the effects of BR functional analogue DI-31 in soybean physiology under drought by assessing changes in growth, photosynthesis, water relations, antioxidant metabolism, nodulation, and nitrogen homeostasis. Moreover, DI-31 application frequencies' effects on crop cycle and commercial cultivar yield stabilisation under drought were assessed. A single foliar application of DI-31 favoured plant drought tolerance, preventing reductions in canopy development and enhancing plant performance and water use since the early stages of stress. The analogue also increased the antioxidant response, favouring nitrogen homeostasis maintenance and attenuating the nodular senescence. Moreover, foliar applications of DI-31 every 21 days enhanced the absolute yield by ~ 9% and reduced drought-induced yield losses by ~ 7% in four commercial cultivars, increasing their drought tolerance efficiency by ~ 12%. These findings demonstrated the practical value of DI-31 as an environmentally friendly alternative for integrative soybean resilience management under drought.
PMID: 35788151
Plant Physiol Biochem , IF:4.27 , 2022 Aug , V185 : P325-335 doi: 10.1016/j.plaphy.2022.06.011
ZmBSK1 positively regulates BR-induced H2O2 production via NADPH oxidase and functions in oxidative stress tolerance in maize.
Provincial Key Laboratory of Agrobiology, Institute of Food Crops, Jiangsu Academy of Agricultural Sciences, Nanjing, 210014, Jiangsu, China.; Provincial Key Laboratory of Agrobiology, Institute of Food Crops, Jiangsu Academy of Agricultural Sciences, Nanjing, 210014, Jiangsu, China; College of Life Sciences, Nanjing Agricultural University, Nanjing, 210095, Jiangsu, China.; Provincial Key Laboratory of Agrobiology, Institute of Food Crops, Jiangsu Academy of Agricultural Sciences, Nanjing, 210014, Jiangsu, China. Electronic address: chenyp@jaas.ac.cn.; Provincial Key Laboratory of Agrobiology, Institute of Food Crops, Jiangsu Academy of Agricultural Sciences, Nanjing, 210014, Jiangsu, China. Electronic address: yuanjh1123@163.com.
Brassinosteroid (BR) has been indicated to induce the production of hydrogen peroxide (H2O2) in plants in response to various environmental stimuli. However, it remains largely unknown how BR induces H2O2 production. In this study, we found that BR treatment significantly raised the kinase activity of maize (Zea mays L.) brassinosteroid-signaling kinase 1 (ZmBSK1) using the immunoprecipitation kinase assay. ZmBSK1 could modulate the gene expressions and activities of nicotinamide adenine dinucleotide phosphate (NADPH) oxidases (EC 1.6.3.1) to modulate BR-induced H2O2 production. BR could enhance the interaction between ZmBSK1 and maize calcium/calmodulin-dependent protein kinase (ZmCCaMK), a previously identified substrate of ZmBSK1. The BR-induced phosphorylation and kinase activity of ZmCCaMK are dependent on ZmBSK1. Moreover, we showed that ZmBSK1 regulated the NADPH oxidase gene expression and activity via directly phosphorylating ZmCCaMK. Genetic analysis suggested that ZmBSK1-ZmCCaMK module strengthened plant tolerance to oxidative stress induced by exogenous application of H2O2 through improving the activities of antioxidant defense enzyme and alleviating the malondialdehyde (MDA) accumulation and electrolyte leakage rate. In conclusion, these findings provide the new insights of ZmBSK1 functioning in BR-induced H2O2 production and the theoretical supports for breeding stress-tolerant crops.
PMID: 35738188
Plant Physiol Biochem , IF:4.27 , 2022 Aug , V185 : P69-79 doi: 10.1016/j.plaphy.2022.05.034
Integrated transcriptomic and gibberellin analyses reveal genes related to branch development in Eucalyptus urophylla.
Guangdong Provincial Key Laboratory of Silviculture, Protection and Utilization/Guangdong Academy of Forestry, Guangzhou, 510520, China.; Guangdong Provincial Key Laboratory of Silviculture, Protection and Utilization/Guangdong Academy of Forestry, Guangzhou, 510520, China. Electronic address: panwen@sinogaf.cn.; Guangdong Provincial Key Laboratory of Silviculture, Protection and Utilization/Guangdong Academy of Forestry, Guangzhou, 510520, China. Electronic address: xiaohuiyang@sinogaf.cn.
Tree branches affect the planting density and basal scab, which act as important attributes in the yield and quality of trees. Eucalyptus urophylla is an important pioneer tree with characteristics of strong adaptability, fast growth, short rotation period, and low disease and pest pressures. In this study, we collected ZQUC14 and LDUD26 clones and compared their transcriptomes and metabolomes from mature xylem, phloem, and developing tissues to identify factors that may influence branch development. In total, 32,809 differentially expressed genes (DEGs) and 18 gibberellin (GA) hormones were detected in the five sampled tissues. Searches of the kyoto Encyclopedia of Genes and Genomes pathways identified mainly genes related to diterpenoid biosynthesis, plant MAPK signaling pathways, plant hormone signal transduction, glycerolipid metabolism, peroxisome, phenylpropanoid biosynthesis, ABC transporters, and brassinosteroid biosynthesis. Furthermore, gene expression trend analysis and weighted gene co-expression network analysis revealed 13 genes likely involved in diterpenoid biosynthesis, including five members of the 2OG-Fe(II) oxygenase superfamily, four cytochrome P450 genes, and four novel genes. In GA signal transduction pathways, 24 DEGs were found to positively regulate branch formation. These results provide a comprehensive analysis of branch development based on the transcriptome and metabolome, and help clarify the molecular mechanisms of E. urophylla.
PMID: 35661587
BMC Plant Biol , IF:4.215 , 2022 Jul , V22 (1) : P319 doi: 10.1186/s12870-022-03701-x
Integrated transcriptome and hormonal analysis of naphthalene acetic acid-induced adventitious root formation of tea cuttings (Camellia sinensis).
Key Laboratory of Tea Biology and Resources Utilization, Ministry of Agriculture, National Center for Tea Improvement, Tea Research Institute Chinese Academy of Agricultural Sciences (TRICAAS), Hangzhou, 310008, China.; Tea Research Institute, Yunnan Academy of Agricultural Sciences, Menghai, 666201, China.; Tea Research Institute of Enshi Academy of Agricultural Sciences, Enshi, 445000, China.; Tea Research Institute of Enshi Academy of Agricultural Sciences, Enshi, 445000, China. hbeshsz@yahoo.com.cn.; Key Laboratory of Tea Biology and Resources Utilization, Ministry of Agriculture, National Center for Tea Improvement, Tea Research Institute Chinese Academy of Agricultural Sciences (TRICAAS), Hangzhou, 310008, China. wangly@tricaas.com.; Key Laboratory of Tea Biology and Resources Utilization, Ministry of Agriculture, National Center for Tea Improvement, Tea Research Institute Chinese Academy of Agricultural Sciences (TRICAAS), Hangzhou, 310008, China. weikang@tricaas.com.
BACKGROUND: Tea plant breeding or cultivation mainly involves propagation via cuttings, which not only ensures the inheritance of the excellent characteristics of the mother plant but also facilitates mechanized management. The formation of adventitious root (AR) determines the success of cutting-based propagation, and auxin is an essential factor involved in this process. To understand the molecular mechanism underlying AR formation in nodal tea cuttings, transcriptome and endogenous hormone analysis was performed on the stem bases of red (mature)- and green (immature)-stem cuttings of 'Echa 1 hao' tea plant as affected by a pulse treatment with naphthalene acetic acid (NAA). RESULTS: In this study, NAA significantly promoted AR formation in both red- and green-stem cuttings but slightly reduced callus formation. External application of NAA reduced the levels of endogenous indole-3-acetic acid (IAA) and cytokinin (TZR, trans-zeatin riboside). The number of DEGs (NAA vs. CK) identified in the green-stem cuttings was significantly higher than that in the red-stem cuttings, which corresponded to a higher rooting rate of green-stem cuttings under the NAA treatment. A total of 82 common DEGs were identified as being hormone-related and involved in the auxin, cytokinin, abscisic acid, ethylene, salicylic acid, brassinosteroid, and jasmonic acid pathways. The negative regulation of NAA-induced IAA and GH3 genes may explain the decrease of endogenous IAA. NAA reduced endogenous cytokinin levels and further downregulated the expression of cytokinin signalling-related genes. By the use of weighted gene co-expression network analysis (WGCNA), several hub genes, including three [cellulose synthase (CSLD2), SHAVEN3-like 1 (SVL1), SMALL AUXIN UP RNA (SAUR21)] that are highly related to root development in other crops, were identified that might play important roles in AR formation in tea cuttings. CONCLUSIONS: NAA promotes the formation of AR of tea cuttings in coordination with endogenous hormones. The most important endogenous AR inductor, IAA, was reduced in response to NAA. DEGs potentially involved in NAA-mediated AR formation of tea plant stem cuttings were identified via comparative transcriptome analysis. Several hub genes, such as CSLD2, SVL1 and SAUR21, were identified that might play important roles in AR formation in tea cuttings.
PMID: 35787241
Planta , IF:4.116 , 2022 Jul , V256 (2) : P27 doi: 10.1007/s00425-022-03939-7
Natural variation of the BRD2 allele affects plant height and grain size in rice.
School of Life Sciences, Xiamen University, Xiamen, China.; Quanzhou Agricultural Science Institute, Quanzhou, 362212, China.; Key Laboratory of Ministry of Education for Genetic Improvement and Comprehensive Utilization of Crops, Fujian Provincial Key Laboratory of Crop Breeding by Design, College of Agriculture, Fujian Agriculture and Forestry University, Fuzhou, China.; School of Life Sciences, Xiamen University, Xiamen, China. huangrongyu@xmu.edu.cn.
MAIN CONCLUSION: The zqdm1 identified from a rice mutant is a novel allele of BRD2 and is responsible for regulating rice plant height, grain size and appearance, which has possibilities on improving rice quality. Plant height is an important agronomic trait related to rice yield, and grain size directly determines grain yield in rice (Oryza sativa L.). With the development of molecular biotechnology and genome sequencing technology, more and more key genes associated with plant height and grain size have been cloned and identified in recent years. This study identified the zqdm1 gene from a mutant with reduced plant height and grain size. The zqdm1 gene was revealed to be a new allele of BRASSINOSTEROID DEFICIENT DWARF 2 (BRD2), encoding a FAD-linked oxidoreductase protein involved in the brassinosteroid (BR) biosynthesis pathway, and regulates plant height by reducing cell number of longitudinal sections of the internode and regulates grain size by altering cell expansion. A 369-bp DNA fragment was found inserted at the first exon, resulting in protein-coding termination. This mutation has not been discovered in previous studies. Complementation tests have confirmed that 369-bp insertion in BRD2 was responsible for the plant height and grain size changing in the zqdm1 mutant. Over-expression of BRD2 driven by different promoters into indica rice variety Jiafuzhan (JFZ) results in slender grains, suggesting its function on regulating grain shape. In summary, the current study has identified a new BRD2 allele, which facilitated the further research on the molecular mechanism of this gene on regulating growth and development.
PMID: 35780402
BMC Genomics , IF:3.969 , 2022 Aug , V23 (1) : P568 doi: 10.1186/s12864-022-08810-3
Evolutionary analysis and functional characterization of BZR1 gene family in celery revealed their conserved roles in brassinosteroid signaling.
College of Life Sciences, North China University of Science and Technology, Tangshan, 063210, Hebei, China.; College of Life Sciences, North China University of Science and Technology, Tangshan, 063210, Hebei, China. yuanmin308@163.com.
BACKGROUND: Brassinosteroids (BRs) are a group of essential steroid hormones involved in diverse developmental and physiological processes in plants. The Brassinazole-resistant 1 (BZR1) transcription factors are key components of BR signaling and integrate a wide range of internal and environmental signals to coordinate plant development, growth, and resistance to abiotic and biotic stresses. Although the BZR1 family has been fully studied in Arabidopsis, celery BZR1 family genes remain largely unknown. RESULTS: Nine BZR1 genes were identified in the celery genome, and categorized into four classes based on phylogenetic and gene structure analyses. All the BZR1 proteins shared a typical bHLH (basic helix-loop-helix) domain that is highly conserved across the whole family in Arabidopsis, grape, lettuce, ginseng, and three Apiaceae species. Both duplications and losses of the BZR1 gene family were detected during the shaping of the celery genome. Whole-genome duplication (WGD) or segmental duplication contributed 55.56% of the BZR1 genes expansion, and the gamma as well as celery-omega polyploidization events made a considerable contribution to the production of the BZR1 paralogs in celery. Four AgBZR1 members (AgBZR1.1, AgBZR1.3, AgBZR1.5, and AgBZR1.9), which were localized both in the nucleus and cytoplasm, exhibit transcription activation activity in yeast. AgBZR1.5 overexpression transgenic plants in Arabidopsis showed curled leaves with bent, long petioles and constitutive BR-responsive phenotypes. Furthermore, the AgBZR1 genes possessed divergent expression patterns with some overlaps in roots, petioles, and leaves, suggesting an extensive involvement of AgBZR1s in the developmental processes in celery with both functional redundancy and divergence. CONCLUSIONS: Our results not only demonstrated that AgBZR1 played a conserved role in BR signaling but also suggested that AgBZR1 might be extensively involved in plant developmental processes in celery. The findings lay the foundation for further study on the molecular mechanism of the AgBZR1s in regulating the agronomic traits and environmental adaptation of celery, and provide insights for future BR-related genetic breeding of celery and other Apiaceae crops.
PMID: 35941544
Biomed Res Int , IF:3.411 , 2022 , V2022 : P8445484 doi: 10.1155/2022/8445484
Transcriptomic Insight into Viviparous Growth in Water Lily.
Flower Research Institute of Guangxi Academy of Agricultural Sciences, Nanning Guangxi 530007, China.; Flower Research Institute of Yunnan Academy of Agricultural Sciences, Kunming Yunnan 650200, China.; National Engineering Research Center for Ornamental Horticulture, Kunming Yunnan 650200, China.
Water lily is an important ornamental flower plant which is capable of viviparous plantlet development. But no study has been reported on the molecular basis of viviparity in water lily. Hence, we performed a comparative transcriptome study between viviparous water lily Nymphaea micrantha and a nonviviparous species Nymphaea colorata at four developmental stages. The higher expression of highly conserved AUX/IAA, ARF, GH3, and SAUR gene families in N. micrantha compared to N. colorata is predicted to have a major impact on the development and evolution of viviparity in water lily. Likewise, differential regulation of hormone signaling, brassinosteroid, photosynthesis, and energy-related pathways in the two species provide clues of their involvement in viviparity phenomenon. This study revealed the complex mechanism of viviparity trait in water lily. The transcriptomic signatures identified are important basis for future breeding and research of viviparity in water lily and other plant species.
PMID: 35845943
J Struct Biol , IF:2.867 , 2022 Aug , V214 (3) : P107885 doi: 10.1016/j.jsb.2022.107885
Structure of maize BZR1-type beta-amylase BAM8 provides new insights into its noncatalytic adaptation.
Department of Plant Biology, College of Biological Sciences, University of California, Davis, CA 95616, USA.; Department of Plant Biology, College of Biological Sciences, University of California, Davis, CA 95616, USA. Electronic address: nshabek@ucdavis.edu.
Plant beta-amylase (BAM) proteins play an essential role in growth, development, stress response, and hormone regulation. Despite their typical (beta/alpha)8 barrel structure as active catalysts in starch breakdown, catalytically inactive BAMs are implicated in diverse yet elusive functions in plants. The noncatalytic BAM7/8 contain N-terminal BZR1 domains and were shown to be involved in the regulation of brassinosteroid signaling and possibly serve as sensors of yet an uncharacterized metabolic signal. While the structures of several catalytically active BAMs have been reported, structural characterization of the catalytically inactive BZR1-type BAMs remain unknown. Here, we determine the crystal structure of beta-amylase domain of Zea mays BAM8/BES1/BZR1-5 and provide comprehensive insights into its noncatalytic adaptation. Using structural-guided comparison combined with biochemical analysis and molecular dynamics simulations, we revealed conformational changes in multiple distinct highly conserved regions resulting in rearrangement of the binding pocket. Altogether, this study adds a new layer of understanding to starch breakdown mechanism and elucidates the acquired adjustments of noncatalytic BZR1-type BAMs as putative regulatory domains and/or metabolic sensors in plants.
PMID: 35961473
Biosci Biotechnol Biochem , IF:2.043 , 2022 Jul , V86 (8) : P1004-1012 doi: 10.1093/bbb/zbac074
Structure modification of nonsteroidal brassinolide-like compound, NSBR1.
Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University, Kyoto, Japan.; Central Pharmaceutical Research Institute, Japan Tobacco Inc., 1-1 Murasaki-cho, Takatsuki, Osaka, Japan.; Graduate School of Biostudies, Kyoto University, Kyoto, Japan.
Brassinolide (BL) is a possible plant growth regulator in agriculture, but the presence of a steroid skeleton hampers the field application of BL in agriculture because of its high synthetic cost. We discovered NSBR1 as the first nonsteroidal BL-like compound using in silico technology. Searching for more potent BL-like compounds, we modified the structure of NSBR1 with respect to 2 benzene rings and the piperazine ring. The activity of synthesized compounds was measured in Arabidopsis hypocotyl elongation. The propyl group of butyryl moiety of NSBR1 was changed to various alkyl groups, such as straight, branched, and cyclic alkyl chains. Another substituent, F, at the ortho position of the B ring toward the piperazine ring was changed to other substituents. A methyl group was introduced to the piperazine ring. Most of the newly synthesized compounds with the 3,4-(OH)2 group at the A ring significantly elongated the hypocotyl of Arabidopsis.
PMID: 35687006
Biosci Biotechnol Biochem , IF:2.043 , 2022 Jul , V86 (8) : P1041-1048 doi: 10.1093/bbb/zbac071
BRZ-INSENSITIVE-PALE GREEN 1 is encoded by chlorophyll biosynthesis enzyme gene that functions in the downstream of brassinosteroid signaling.
Graduate School of Biostudies, Kyoto University, KItashirakawa-Oiwake-cho, Sakyo-ku, Kyoto, Japan.; Department of Biology, Ochanomizu University, Bunkyo-ku, Tokyo, Japan.; RIKEN, CSRS, Tsurumi-ku, Yokohama, Japan.; The Institute of Oncology, Riga Stradins University, 16 Dzirciema Street, Riga, Latvia.; Organization for the Strategic Coordination of Research and Intellectual Properties, Meiji University, Tama-ku, Kawasaki, Japan.; Institute of Low Temperature Science, Hokkaido University, Kita-ku, Sapporo, Japan.; Department of Applied Biological Chemistry, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Bunkyo-ku, Tokyo, Japan.
Brassinosteroids (BRs), a kind of phytohormone, have various biological activities such as promoting plant growth, increasing stress resistance, and chloroplast development. Though BRs have been known to have physiological effects on chloroplast, the detailed mechanism of chloroplast development and chlorophyll biosynthesis in BR signaling remains unknown. Here we identified a recessive pale green Arabidopsis mutant, Brz-insensitive-pale green1 (bpg1), which was insensitive to promoting of greening by BR biosynthesis-specific inhibitor Brz in the light. BPG1 gene encoded chlorophyll biosynthesis enzyme, 3, 8-divinyl protochlorophyllide a 8-vinyl reductase (DVR), and bpg1 accumulated divinyl chlorophylls. Chloroplast development was suppressed in bpg1. Brz dramatically increased the expression of chlorophyll biosynthesis enzyme genes, including BPG1. These results suggest that chlorophyll biosynthesis enzymes are regulated by BR signaling in the aspect of gene expression and BPG1 plays an important role in regulating chloroplast development.
PMID: 35583242
Plant Commun , 2022 Aug : P100419 doi: 10.1016/j.xplc.2022.100419
Brassinosteroids promote thermotolerance through releasing BIN2-mediated phosphorylation and suppression of HsfA1 transcription factors in Arabidopsis.
College of Life Science and Technology, Huazhong Agricultural University, Wuhan 430070, China; State Key Laboratory of Crop Stress Adaptation and Improvement, Henan University, Kaifeng 475004, China; Sanya Institute of Henan University, Sanya 572025, China.; State Key Laboratory of Crop Stress Adaptation and Improvement, Henan University, Kaifeng 475004, China.; State Key Laboratory of Crop Stress Adaptation and Improvement, Henan University, Kaifeng 475004, China; Sanya Institute of Henan University, Sanya 572025, China. Electronic address: xueluw@henu.edu.cn.
High temperature adversely affects plant growth and development. The steroid phytohormones, brassinosteroids (BRs), are recognized to play important roles in plant heat stress responses and thermotolerance, while the underlying mechanisms remain obscure. Here, we demonstrate that glycogen synthase kinase 3 (GSK3)-like kinase BRASSINOSTEROID INSENSITIVE2 (BIN2), a negative component in the BR signaling pathway, interacts with the master heat responsive transcription factors CLASS A1 HEAT SHOCK TRANSCRIPTION FACTORS (HsfA1s). Furthermore, BIN2 phosphorylates HsfA1d on T263 and S56 to suppress its nuclear localization and inhibit its DNA binding ability, respectively. BR signaling promotes plant thermotolerance by releasing the BIN2 suppression on HsfA1d to facilitate its nuclear localization and DNA binding. Our study provides insights into the molecular mechanisms of BR promoting plant thermotolerance by largely regulating HsfA1d through BIN2 and suggests potential ways to improve crop yield under extreme high temperatures.
PMID: 35927943
Braz J Biol , 2022 , V82 : Pe260818 doi: 10.1590/1519-6984.260818
Mitigation of the effects of salt stress in cowpea bean through the exogenous aplication of brassinosteroid.
Universidade Federal Rural da Amazonia - UFRA, Instituto de Ciencias Agrarias, Laboratorio de Fisiologia Vegetal, Grupo de Estudos da Biodiversidade em Plantas Superiores, Belem, PA, Brasil.; Universidade Federal Rural da Amazonia - UFRA, Instituto de Ciencias Agrarias, Laboratorio de Fisiologia Vegetal, Grupo de Estudos da Biodiversidade em Plantas Superiores, Parauapebas, PA, Brasil.
Cowpea (Vigna unguiculata (L.) Walp.) is a legume widely cultivated by small, medium and large producers in several Brazilian regions. However, one of the concerns for the production of cowpea in Brazil in recent years is the low rainfall activity in these regions, which generates the accumulation of salts on the surface. The objective of this work was to evaluate the effects of salt stress on growth parameters and enzyme activity in cowpea plants at different concentrations of brassinosteroids. Experiment was developed in a greenhouse using a completely randomized experimental design in a 3 x 3 factorial scheme. The treatments consisted of three levels of brassinosteroids (0, 3 and 6 microM EBL) and three levels of salt stress (0, 50 and 100 mM NaCl). Growth factors (height, diameter and number of leaves) decreased in the saline condition. With the presence of brassinosteroid the height did not increase, but the number of leaves did, mainly in the saline dosage of 100 mM NaCl. In the variable membrane integrity, brassinosteroid was efficient in both salinity dosages, the same not happening with the relative water content, where the saline condition did not affect the amount of water in the vegetable, with the application of brassino it remained high, decreasing only at dosage 100 mM NaCl. The nitrate reductase enzyme was greatly affected in the root system even with the application of increasing doses of brassino. Therefore, brassinosteroids as a promoter of saline tolerance in cowpea seedlings was positive. The concentration of 3microM of EBL provided the most satisfactory effect in tolerating the deleterious effects of the saline condition. The same cannot be concluded for the concentration of 6microM of EBL that did not promote tolerance to some variables.
PMID: 35857948
Plant Commun , 2022 Jul , V3 (4) : P100317 doi: 10.1016/j.xplc.2022.100317
A reference-guided TILLING by amplicon-sequencing platform supports forward and reverse genetics in barley.
Institute of Crop Sciences, Chinese Academy of Agricultural Sciences, Beijing, China.; Institute of Crop Sciences, Chinese Academy of Agricultural Sciences, Beijing, China; College of Agronomy, Sichuan Agricultural University, Chengdu, China.; Leibniz Institute of Plant Genetics and Crop Plant Research (IPK), Seeland, Germany.; Institute of Botany, Chinese Academy of Sciences, Beijing, China.; Plant Genome and Systems Biology (PGSB), Helmholtz Center Munich, German Research Center for Environmental Health, Neuherberg, Germany.; College of Agronomy, Sichuan Agricultural University, Chengdu, China.; Leibniz Institute of Plant Genetics and Crop Plant Research (IPK), Seeland, Germany. Electronic address: mascher@ipk-gatersleben.de.; Institute of Crop Sciences, Chinese Academy of Agricultural Sciences, Beijing, China. Electronic address: yangping@caas.cn.
Barley is a diploid species with a genome smaller than those of other members of the Triticeae tribe, making it an attractive model for genetic studies in Triticeae crops. The recent development of barley genomics has created a need for a high-throughput platform to identify genetically uniform mutants for gene function investigations. In this study, we report an ethyl methanesulfonate (EMS)-mutagenized population consisting of 8525 M3 lines in the barley landrace "Hatiexi" (HTX), which we complement with a high-quality de novo assembly of a reference genome for this genotype. The mutation rate within the population ranged from 1.51 to 4.09 mutations per megabase, depending on the treatment dosage of EMS and the mutation discrimination platform used for genotype analysis. We implemented a three-dimensional DNA pooling strategy combined with multiplexed amplicon sequencing to create a highly efficient and cost-effective TILLING (targeting induced locus lesion in genomes) platform in barley. Mutations were successfully identified from 72 mixed amplicons within a DNA pool containing 64 individual mutants and from 56 mixed amplicons within a pool containing 144 individuals. We discovered abundant allelic mutants for dozens of genes, including the barley Green Revolution contributor gene Brassinosteroid insensitive 1 (BRI1). As a proof of concept, we rapidly determined the causal gene responsible for a chlorotic mutant by following the MutMap strategy, demonstrating the value of this resource to support forward and reverse genetic studies in barley.
PMID: 35605197