Nat Biotechnol , IF:54.908 , 2023 Mar doi: 10.1038/s41587-023-01707-w
Tuning plant phenotypes by precise, graded downregulation of gene expression.
State Key Laboratory of Plant Cell and Chromosome Engineering, Center for Genome Editing, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, China.; College of Advanced Agricultural Sciences, University of Chinese Academy of Sciences, Beijing, China.; Qi Biodesign, Beijing, China.; State Key Laboratory of Plant Cell and Chromosome Engineering, Center for Genome Editing, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, China. cxgao@genetics.ac.cn.; College of Advanced Agricultural Sciences, University of Chinese Academy of Sciences, Beijing, China. cxgao@genetics.ac.cn.
The ability to control gene expression and generate quantitative phenotypic changes is essential for breeding new and desired traits into crops. Here we report an efficient, facile method for downregulating gene expression to predictable, desired levels by engineering upstream open reading frames (uORFs). We used base editing or prime editing to generate de novo uORFs or to extend existing uORFs by mutating their stop codons. By combining these approaches, we generated a suite of uORFs that incrementally downregulate the translation of primary open reading frames (pORFs) to 2.5-84.9% of the wild-type level. By editing the 5' untranslated region of OsDLT, which encodes a member of the GRAS family and is involved in the brassinosteroid transduction pathway, we obtained, as predicted, a series of rice plants with varied plant heights and tiller numbers. These methods offer an efficient way to obtain genome-edited plants with graded expression of traits.
PMID: 36894598
Trends Plant Sci , IF:18.313 , 2023 Apr , V28 (4) : P399-414 doi: 10.1016/j.tplants.2022.12.006
Mass spectrometric exploration of phytohormone profiles and signaling networks.
State Key Laboratory of Plant Physiology and Biochemistry, College of Biological Sciences, China Agricultural University, 100193, Beijing, China. Electronic address: chenym@cau.edu.cn.; State Key Laboratory of Wheat and Maize Crop Science, College of Resources and Environment, Henan Agricultural University, 450002, Zhengzhou, China.; State Key Laboratory of Plant Physiology and Biochemistry, College of Biological Sciences, China Agricultural University, 100193, Beijing, China.; Center of Plant Systems Biology and Biotechnology, 4000 Plovdiv, Bulgaria; Max-Planck-Institute of Molecular Plant Physiology, 14476 Potsdam-Golm, Germany.
Phytohormones have crucial roles in plant growth, development, and acclimation to environmental stress; however, measuring phytohormone levels and unraveling their complex signaling networks and interactions remains challenging. Mass spectrometry (MS) has revolutionized the study of complex biological systems, enabling the comprehensive identification and quantification of phytohormones and their related targets. Here, we review recent advances in MS technologies and highlight studies that have used MS to discover and analyze phytohormone-mediated molecular events. In particular, we focus on the application of MS for profiling phytohormones, elucidating phosphorylation signaling, and mapping protein interactions in plants.
PMID: 36585336
Autophagy , IF:16.016 , 2023 Apr , V19 (4) : P1293-1310 doi: 10.1080/15548627.2022.2124501
Brassinosteroids modulate autophagy through phosphorylation of RAPTOR1B by the GSK3-like kinase BIN2 in Arabidopsis.
Department of Genetics, Development and Cell Biology, Iowa State University, Ames, IA, USA.; Department of Plant Pathology and Microbiology, Iowa State University, Ames, IA, USA.
Macroautophagy/autophagy is a conserved recycling process that maintains cellular homeostasis during environmental stress. Autophagy is negatively regulated by TOR (target of rapamycin), a nutrient-regulated protein kinase that in plants is activated by several phytohormones, leading to increased growth. However, the detailed molecular mechanisms by which TOR integrates autophagy and hormone signaling are poorly understood. Here, we show that TOR modulates brassinosteroid (BR)-regulated plant growth and stress-response pathways. Active TOR was required for full BR-mediated growth in Arabidopsis thaliana. Autophagy was constitutively up-regulated upon blocking BR biosynthesis or signaling, and down-regulated by increasing the activity of the BR pathway. BIN2 (brassinosteroid-insensitive 2) kinase, a GSK3-like kinase functioning as a negative regulator in BR signaling, directly phosphorylated RAPTOR1B (regulatory-associated protein of TOR 1B), a substrate-recruiting subunit in the TOR complex, at a conserved serine residue within a typical BIN2 phosphorylation motif. Mutation of RAPTOR1B serine 916 to alanine, to block phosphorylation by BIN2, repressed autophagy and increased phosphorylation of the TOR substrate ATG13a (autophagy-related protein 13a). By contrast, this mutation had only a limited effect on growth. We present a model in which RAPTOR1B is phosphorylated and inhibited by BIN2 when BRs are absent, activating the autophagy pathway. When BRs signal and inhibit BIN2, RAPTOR1B is thus less inhibited by BIN2 phosphorylation. This leads to increased TOR activity and ATG13a phosphorylation, and decreased autophagy activity. Our studies define a new mechanism by which coordination between BR and TOR signaling pathways helps to maintain the balance between plant growth and stress responses.
PMID: 36151786
EMBO J , IF:11.598 , 2023 Feb , V42 (4) : Pe111883 doi: 10.15252/embj.2022111883
Brassinosteroid signals cooperate with katanin-mediated microtubule severing to control stamen filament elongation.
State Key Laboratory of Plant Genomics, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China.; University of Chinese Academy of Sciences, Beijing, China.; Houji Laboratory of Shanxi Province, Academy of Agronomy, Shanxi Agricultural University, Taiyuan, China.; Institute of Feed Research, Chinese Academy of Agricultural Sciences, Beijing, China.; Guangdong Provincial Key Laboratory of Plant Adaptation and Molecular Design, School of Life Sciences, Guangzhou University, Guangzhou, China.; State Key Laboratory of Plant Cell and Chromosome Engineering, Institute of Genetics and Developmental Biology, Innovative Academy of Seed Design, Chinese Academy of Sciences, Beijing, China.
Proper stamen filament elongation is essential for pollination and plant reproduction. Plant hormones are extensively involved in every stage of stamen development; however, the cellular mechanisms by which phytohormone signals couple with microtubule dynamics to control filament elongation remain unclear. Here, we screened a series of Arabidopsis thaliana mutants showing different microtubule defects and revealed that only those unable to sever microtubules, lue1 and ktn80.1234, displayed differential floral organ elongation with less elongated stamen filaments. Prompted by short stamen filaments and severe decrease in KTN1 and KTN80s expression in qui-2 lacking five BZR1-family transcription factors (BFTFs), we investigated the crosstalk between microtubule severing and brassinosteroid (BR) signaling. The BFTFs transcriptionally activate katanin-encoding genes, and the microtubule-severing frequency was severely reduced in qui-2. Taken together, our findings reveal how BRs can regulate cytoskeletal dynamics to coordinate the proper development of reproductive organs.
PMID: 36546550
Plant Cell , IF:11.277 , 2023 Mar doi: 10.1093/plcell/koad060
Brassinosteroids regulate cotton fiber elongation by modulating very-long-chain fatty acid biosynthesis.
Zhengzhou Research Base, State Key Laboratory of Cotton Biology, School of Agricultural Sciences, Zhengzhou University, Zhengzhou, 450001, Henan, China.; State Key Laboratory of Cotton Biology, Institute of Cotton Research, Chinese Academy of Agricultural Sciences, Anyang, 455000, Henan, China.; Western Agricultural Research Center, Chinese Academy of Agricultural Sciences, Changji 831100, Xinjiang, China.
Brassinosteroid (BR), a growth-promoting phytohormone, regulates many plant growth processes including cell development. However, the mechanism by which BR regulates fiber growth is poorly understood. Cotton (Gossypium hirsutum) fibers are an ideal single-cell model in which to study cell elongation due to their length. Here we report that BR controls cotton fiber elongation by modulating very-long-chain fatty acid (VLCFA) biosynthesis. BR deficiency reduces the expression of 3-ketoacyl-CoA synthases (GhKCSs), the rate-limiting enzymes involved in VLCFA biosynthesis, leading to lower saturated VLCFAs contents in pagoda1 (pag1) mutant fibers. In vitro ovule culture experiments show that BR acts upstream of VLCFAs. Silencing of BRI1-EMS-SUPPRESOR 1.4 (GhBES1.4), encoding a master transcription factor (TF) of the BR signaling pathway, significantly reduces fiber length, whereas GhBES1.4 over-expression produces longer fibers. GhBES1.4 regulates endogenous VLCFA contents and directly binds to BR RESPONSE ELEMENTS (BRREs) in the GhKCS10_At promoter region, which in turn regulates GhKCS10_At expression to increase endogenous VLCFA contents. GhKCS10_At overexpression promotes cotton fiber elongation, whereas GhKCS10_At silencing inhibits cotton fiber growth, supporting a positive regulatory role for GhKCS10_At in fiber elongation. Overall, these results uncover a mechanism of fiber elongation through crosstalk between BR and VLCFAs at the single-cell level.
PMID: 36861340
Plant Cell , IF:11.277 , 2023 Feb doi: 10.1093/plcell/koad040
Don't be blue: Pure green light spurs brassinosteroid signaling.
Assistant Features Editor, The Plant Cell, American Society of Plant Biologists, USA.; Department of Botany and Plant Sciences, University of California Riverside, CA.
PMID: 36808293
Plant Cell , IF:11.277 , 2023 Feb doi: 10.1093/plcell/koad032
Signaling by the EPFL-ERECTA family coordinates female germline specification through the BZR1 family in Arabidopsis.
College of Life Sciences, Fujian Provincial Key Laboratory of Haixia Applied Plant Systems Biology, State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops, Fujian Agriculture and Forestry University, Fuzhou 350002, China.; Cell Biology and Plant Biochemistry, University of Regensburg, 93053 Regensburg, Germany.; Tea Research Institute, Guangdong Academy of Agricultural Sciences & Guangdong Provincial Key Laboratory of Tea Plant Resources Innovation and Utilization, Dafeng Road 6, Tianhe District, Guangzhou 510640.; State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, Guangxi Key Lab of Sugarcane Biology, College of Agriculture, Guangxi University, Nanning 530004, China.
In most flowering plants, the female germline is initiated in the subepidermal L2 layer of ovule primordia forming a single megaspore mother cell (MMC). How signaling from the L1 (epidermal) layer could contribute to the gene regulatory network restricting MMC formation to a single cell is unclear. We show that EPIDERMAL PATTERNING FACTOR-like (EPFL) peptide ligands are expressed in the L1 layer, together with their ERECTA family (ERf) receptor kinases, to control female germline specification in Arabidopsis thaliana. EPFL-ERf dependent signaling restricts multiple subepidermal cells from acquiring MMC-like cell identity by activating the expression of the major brassinosteroid (BR) receptor kinase BRASSINOSTEROID INSENSITIVE 1 (BRI1) and the BR-responsive transcription factor BRASSINOZOLE RESISTANT 1 (BZR1). Additionally, BZR1 coordinates female germline specification by directly activating the expression of a nucleolar GTP-binding protein, NUCLEOSTEMIN-LIKE 1 (NSN1), which is expressed in early-stage ovules excluding the MMC. Mutants defective in this gene regulatory network form multiple MMCs resulting in a strong reduction of seed set. In conclusion, we uncovered a ligand/receptor-like kinase-mediated signaling pathway acting upstream and coordinating BR signaling via NSN1 to restrict MMC differentiation to a single subepidermal cell.
PMID: 36748257
Plant Cell , IF:11.277 , 2023 Feb doi: 10.1093/plcell/koad022
Green means go: Green light promotes hypocotyl elongation via brassinosteroid signaling.
National Key Laboratory of Plant Molecular Genetics, CAS Center for Excellence in Molecular Plant Sciences, Institute of Plant Physiology and Ecology, Chinese Academy of Sciences, 200031 Shanghai, P. R.China.; University of Chinese Academy of Sciences, Shanghai 200031, P. R.China.; Department of Light Source and Illuminating Engineering, Fudan University, 2005 Songhu Rd, Shanghai 200433, P. R.China.
Although many studies have elucidated the mechanisms by which different wavelengths of light (blue, red, far-red or ultraviolet-B [UV-B]) regulate plant development, whether and how green light regulates plant development remains largely unknown. Previous studies reported that green light participates in regulating growth and development in land plants, but these studies have reported conflicting results, likely due to technical problems. For example, commercial green LED light sources emit a little blue or red light. Here, using a pure green light source, we determined that unlike blue, red, far-red or UV-B light, which inhibit hypocotyl elongation, green light promotes hypocotyl elongation in Arabidopsis thaliana and several other plants during first the 2-3 days after planting. Phytochromes, cryptochromes, and other known photoreceptors do not mediate green light-promoted hypocotyl elongation, but the brassinosteroid signaling pathway is involved in this process. Green light promotes the DNA binding activity of BRI1-EMS-SUPPRESSOR 1 (BES1), a master transcription factor of the brassinosteroid pathway, thus regulating gene transcription to promote hypocotyl elongation. Our results indicate that pure green light promotes elongation via brassinosteroid signaling and acts as a shade signal to enable plants to adapt their development to a green-light-dominant environment under a canopy.
PMID: 36724050
Plant Cell , IF:11.277 , 2023 Mar , V35 (3) : P975-993 doi: 10.1093/plcell/koad013
Mapping the signaling network of BIN2 kinase using TurboID-mediated biotin labeling and phosphoproteomics.
Department of Plant Biology, Carnegie Institution for Science, Stanford, California 94305, USA.; Department of Life Science, Hanyang University, Seoul 04763, South Korea.; Research Institute for Convergence of Basic Science, Hanyang University, Seoul 04763, South Korea.; Institute of Plant and Microbial Biology, Academia Sinica, Taipei 11529, Taiwan.; Departments of Genetics, Biology, and Chemistry, Stanford University, Stanford, California 94305, USA.; Department of Biology, Stanford University, Stanford, California 94305, USA.; Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA.; Department of Pharmaceutical Chemistry, University of California, San Francisco, California 94158, USA.; Department of Cell & Systems Biology/Centre for the Analysis of Genome Evolution and Function, University of Toronto, Toronto, Ontario M5S 3B2, Canada.; Chan Zuckerberg Biohub, San Francisco, California, USA.
Elucidating enzyme-substrate relationships in posttranslational modification (PTM) networks is crucial for understanding signal transduction pathways but is technically difficult because enzyme-substrate interactions tend to be transient. Here, we demonstrate that TurboID-based proximity labeling (TbPL) effectively and specifically captures the substrates of kinases and phosphatases. TbPL-mass spectrometry (TbPL-MS) identified over 400 proximal proteins of Arabidopsis thaliana BRASSINOSTEROID-INSENSITIVE2 (BIN2), a member of the GLYCOGEN SYNTHASE KINASE 3 (GSK3) family that integrates signaling pathways controlling diverse developmental and acclimation processes. A large portion of the BIN2-proximal proteins showed BIN2-dependent phosphorylation in vivo or in vitro, suggesting that these are BIN2 substrates. Protein-protein interaction network analysis showed that the BIN2-proximal proteins include interactors of BIN2 substrates, revealing a high level of interactions among the BIN2-proximal proteins. Our proteomic analysis establishes the BIN2 signaling network and uncovers BIN2 functions in regulating key cellular processes such as transcription, RNA processing, translation initiation, vesicle trafficking, and cytoskeleton organization. We further discovered significant overlap between the GSK3 phosphorylome and the O-GlcNAcylome, suggesting an evolutionarily ancient relationship between GSK3 and the nutrient-sensing O-glycosylation pathway. Our work presents a powerful method for mapping PTM networks, a large dataset of GSK3 kinase substrates, and important insights into the signaling network that controls key cellular functions underlying plant growth and acclimation.
PMID: 36660928
Plant Cell , IF:11.277 , 2023 Mar , V35 (4) : P1241-1258 doi: 10.1093/plcell/koad007
Spatiotemporal formation of the large vacuole regulated by the BIN2-VLG module is required for female gametophyte development in Arabidopsis.
School of Life Sciences and Biotechnology, The Joint International Research Laboratory of Metabolic and Developmental Sciences, Shanghai Jiao Tong University, Shanghai 200240, China.; Shanghai Collaborative Innovation Center of Agri-Seeds/Joint Center for Single Cell Biology, Shanghai Jiao Tong University, Shanghai 200240, China.; School of Agriculture and Biology, Joint Center for Single Cell Biology, Shanghai Jiao Tong University, Shanghai 200240, China.; State Key Laboratory of Genetic Engineering and Ministry of Education Key Laboratory of Biodiversity Science and Ecological Engineering and Institute of Biodiversity Sciences, Institute of Plant Biology, Center for Evolutionary Biology, School of Life Sciences, Fudan University, Shanghai 200240, China.
In Arabidopsis thaliana, female gametophyte (FG) development is accompanied by the formation and expansion of the large vacuole in the FG; this is essential for FG expansion, nuclear polar localization, and cell fate determination. Arabidopsis VACUOLELESS GAMETOPHYTES (VLG) facilitates vesicular fusion to form large vacuole in the FG, but the regulation of VLG remains largely unknown. Here, we found that gain-of-function mutation of BRASSINOSTEROID INSENSITIVE2 (BIN2) (bin2-1) increases VLG abundance to induce the vacuole formation at stage FG1, and leads to abortion of FG. Loss-of-function mutation of BIN2 and its homologs (bin2-3 bil1 bil2) reduced VLG abundance and mimicked vlg/VLG phenotypes. Knocking down VLG in bin2-1 decreased the ratio of aberrant vacuole formation at stage FG1, whereas FG1-specific overexpression of VLG mimicked the bin2-1 phenotype. VLG partially rescued the bin2-3 bil1 bil2 phenotype, demonstrating that VLG acts downstream of BIN2. Mutation of VLG residues that are phosphorylated by BIN2 altered VLG stability and a phosphorylation mimic of VLG causes similar defects as did bin2-1. Therefore, BIN2 may function by interacting with and phosphorylating VLG in the FG to enhance its stability and abundance, thus facilitating vacuole formation. Our findings provide mechanistic insight into how the BIN2-VLG module regulates the spatiotemporal formation of the large vacuole in FG development.
PMID: 36648110
Plant Cell , IF:11.277 , 2023 Mar , V35 (3) : P1076-1091 doi: 10.1093/plcell/koac364
An endoplasmic reticulum-associated degradation-related E2-E3 enzyme pair controls grain size and weight through the brassinosteroid signaling pathway in rice.
College of Life Science, University of Chinese Academy of Sciences, Beijing 100049, China.; State Key Laboratory of Plant Cell and Chromosome Engineering, CAS Centre for Excellence in Molecular Plant Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China.; Key Laboratory of Plant Molecular Physiology, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China.; Hainan Yazhou Bay Seed Laboratory, Sanya Nanfan Research Institute of Hainan University, Sanya 572025, China.; College of Tropical Crops Hainan University, Hainan University, Haikou 570288, China.; The Innovative of Seed Design, Chinese Academy of Sciences, Sanya 572025, China.
Grain size is an important agronomic trait, but our knowledge about grain size determination in crops is still limited. Endoplasmic reticulum (ER)-associated degradation (ERAD) is a special ubiquitin proteasome system that is involved in degrading misfolded or incompletely folded proteins in the ER. Here, we report that SMALL GRAIN 3 (SMG3) and DECREASED GRAIN SIZE 1 (DGS1), an ERAD-related E2-E3 enzyme pair, regulate grain size and weight through the brassinosteroid (BR) signaling pathway in rice (Oryza sativa). SMG3 encodes a homolog of Arabidopsis (Arabidopsis thaliana) UBIQUITIN CONJUGATING ENZYME 32, which is a conserved ERAD-associated E2 ubiquitin conjugating enzyme. SMG3 interacts with another grain size regulator, DGS1. Loss of function of SMG3 or DGS1 results in small grains, while overexpression of SMG3 or DGS1 leads to long grains. Further analyses showed that DGS1 is an active E3 ubiquitin ligase and colocates with SMG3 in the ER. SMG3 and DGS1 are involved in BR signaling. DGS1 ubiquitinates the BR receptor BRASSINOSTEROID INSENSITIVE 1 (BRI1) and affects its accumulation. Genetic analysis suggests that SMG3, DGS1, and BRI1 act together to regulate grain size and weight. In summary, our findings identify an ERAD-related E2-E3 pair that regulates grain size and weight, which gives insight into the function of ERAD in grain size control and BR signaling.
PMID: 36519262
Curr Biol , IF:10.834 , 2023 Feb , V33 (4) : P697-710.e6 doi: 10.1016/j.cub.2023.01.013
Hydathode immunity protects the Arabidopsis leaf vasculature against colonization by bacterial pathogens.
Molecular Plant Pathology, Swammerdam Institute for Life Sciences (SILS), University of Amsterdam, Science Park 904, 1098 XH Amsterdam, The Netherlands.; Wageningen Electron Microscopy Centre, Department of Plant Sciences, Wageningen University & Research, Droevendaalsesteeg 4, 6708 PB Wageningen, The Netherlands.; Molecular Plant Pathology, Swammerdam Institute for Life Sciences (SILS), University of Amsterdam, Science Park 904, 1098 XH Amsterdam, The Netherlands. Electronic address: h.a.vandenburg@uva.nl.
Plants prevent disease by passively and actively protecting potential entry routes against invading microbes. For example, the plant immune system actively guards roots, wounds, and stomata. How plants prevent vascular disease upon bacterial entry via guttation fluids excreted from specialized glands at the leaf margin remains largely unknown. These so-called hydathodes release xylem sap when root pressure is too high. By studying hydathode colonization by both hydathode-adapted (Xanthomonas campestris pv. campestris) and non-adapted pathogenic bacteria (Pseudomonas syringae pv. tomato) in immunocompromised Arabidopsis mutants, we show that the immune hubs BAK1 and EDS1-PAD4-ADR1 restrict bacterial multiplication in hydathodes. Both immune hubs effectively confine bacterial pathogens to hydathodes and lower the number of successful escape events of an hydathode-adapted pathogen toward the xylem. A second layer of defense, which is dependent on the plant hormones' pipecolic acid and to a lesser extent on salicylic acid, reduces the vascular spread of the pathogen. Thus, besides glands, hydathodes represent a potent first line of defense against leaf-invading microbes.
PMID: 36731466
Cell Rep , IF:9.423 , 2023 Mar , V42 (4) : P112301 doi: 10.1016/j.celrep.2023.112301
A conserved brassinosteroid-mediated BES1-CERP-EXPA3 signaling cascade controls plant cell elongation.
College of Life Sciences, Shaanxi Normal University, Xi'an 710062, China.; College of Life Sciences, Shaanxi Normal University, Xi'an 710062, China. Electronic address: guanghuix@snnu.edu.cn.
Continuous plant growth is achieved by cell division and cell elongation. Brassinosteroids control cell elongation and differentiation throughout plant life. However, signaling cascades underlying BR-mediated cell elongation are unknown. In this study, we introduce cotton fiber, one of the most representative single-celled tissues, to decipher cell-specific BR signaling. We find that gain of function of GhBES1, a key transcriptional activator in BR signaling, enhances fiber elongation. The chromatin immunoprecipitation sequencing analysis identifies a cell-elongation-related protein, GhCERP, whose transcription is directly activated by GhBES1. GhCERP, a downstream target of GhBES1, transmits the GhBES1-mediated BR signaling to its target gene, GhEXPA3-1. Ultimately, GhEXPA3-1 promotes fiber cell elongation. In addition, inter-species functional analysis of the BR-mediated BES1-CERP-EXPA3 signaling cascade also promotes Arabidopsis root and hypocotyl growth. We propose that the BES1-CERP-EXPA3 module may be a broad-spectrum pathway that is universally exploited by diverse plant species to regulate BR-promoted cell elongation.
PMID: 36952343
Cell Rep , IF:9.423 , 2023 Mar , V42 (3) : P112187 doi: 10.1016/j.celrep.2023.112187
Control of grain size in rice by TGW3 phosphorylation of OsIAA10 through potentiation of OsIAA10-OsARF4-mediated auxin signaling.
Key Laboratory of Plant Molecular Physiology, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China; College of Advanced Agricultural Sciences, University of Chinese Academy of Sciences, Beijing 100049, China.; National Key Laboratory of Rice Biology, China National Rice Research Institute, Hangzhou 310006, China.; Key Laboratory of Plant Molecular Physiology, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China; College of Advanced Agricultural Sciences, University of Chinese Academy of Sciences, Beijing 100049, China; The Innovative Academy of Seed Design, Chinese Academy of Sciences, Beijing 100101, China. Electronic address: songxj@ibcas.ac.cn.
Grain size is a key component of grain yield and quality in crops. Several core players of auxin signaling have been revealed to modulate grain size; however, to date, few genetically defined pathways have been reported, and whether phosphorylation could boost degradation of Aux/IAA proteins is uncertain. Here, we show that TGW3 (also called OsGSK5) interacts with and phosphorylates OsIAA10. Phosphorylation of OsIAA10 facilitates its interaction with OsTIR1 and subsequent destabilization, but this modification hinders its interaction with OsARF4. Our genetic and molecular evidence identifies an OsTIR1-OsIAA10-OsARF4 axis as key for grain size control. In addition, physiological and molecular studies suggest that TGW3 mediates the brassinosteroid response, the effect of which can be relayed through the regulatory axis. Collectively, these findings define a auxin signaling pathway to regulate grain size, in which phosphorylation of OsIAA10 enhances its proteolysis and potentiates OsIAA10-OsARF4-mediated auxin signaling.
PMID: 36871218
Plant Physiol , IF:8.34 , 2023 Feb doi: 10.1093/plphys/kiad117
Armadillo Repeat Only protein GS10 negatively regulates brassinosteroid signaling to control rice grain size.
National Center for Gene Research, CAS Center for Excellence in Molecular Plant Sciences, Institute of Plant Physiology and Ecology, Chinese Academy of Sciences, Shanghai, 200233, China.; School of Life Sciences, Division of Life Sciences and Medicine, University of Science and Technology of China, Chinese Academy of Sciences, Hefei, 230027, China.; State Key Laboratory of Crop Gene Exploration and Utilization in Southwest China, Rice Research Institute, Sichuan Agricultural University at Wenjiang, Chengdu, 611130, China.; College of Life Sciences, Anhui Normal University, Wuhu, Anhui, 241000, China.; School of Life Science and Technology, Shanghai Tech University, Shanghai, 201210, China.; College of Life Sciences, Shanghai Normal University, Shanghai, 200234, China.
Grain yield and grain quality are major determinants in modern breeding controlled by many quantitative traits loci (QTLs) in rice (Oryza sativa). However, the mechanisms underlying grain shape and quality are poorly understood. Here, we characterize a QTL for grain size and grain quality via map-based cloning from wild rice (W1943), GS10 (Grain Size on Chromosome 10), which encodes a protein with six tandem armadillo (ARM) repeats. The null mutant gs10 shows slender and narrow grains with altered cell size, which has a pleiotropic effect on other agronomical traits. Functional analysis reveals that GS10 interacts with TUD1 (Taihu Dwarf1) and is epistatic to OsGSK2 (glycogen synthase kinase 2) through regulating grain shape and lamina joint inclination, indicating it is negatively involved in brassinosteroid (BR) signaling. Pyramiding gs10 and the grain size gene GW5 into cultivar GLA4 substantially improved grain shape and appearance quality. Natural variation analysis revealed that gs10 from the wild rice Oryza rufipogon W1943 is a rare allele across the rice population. Collectively, these findings advance our understanding of the underlying mechanism of grain shape and provide the beneficial allele of gs10 for future rice breeding and genetic improvement.
PMID: 36822628
Plant Physiol , IF:8.34 , 2023 Feb doi: 10.1093/plphys/kiad082
Another tool in the receptor endocytosis kit: Ligand-insensitive BRASSINOSTEROID INSENSITIVE1.
Department of Plant Biology, Carnegie Institution for Science, Stanford, CA 94305.
PMID: 36782385
Plant Physiol , IF:8.34 , 2023 Mar , V191 (3) : P1985-2000 doi: 10.1093/plphys/kiac590
A brassinosteroid transcriptional regulatory network participates in regulating fiber elongation in cotton.
State Key Laboratory of Cotton Biology, Institute of Cotton Research, Chinese Academy of Agricultural Sciences, Anyang 455000, Henan, China.; National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan 430070, Hubei, China.; Zhengzhou Research Base, State Key Laboratory of Cotton Biology, School of Agricultural Sciences, Zhengzhou University, Zhengzhou 450001, Henan, China.; Department of Plant Sciences and Plant Pathology, Montana State University, Bozeman, MT 59717, USA.; Western Agricultural Research Center, Chinese Academy of Agricultural Sciences, Changji 831100, Xinjiang, China.
Brassinosteroids (BRs) participate in the regulation of plant growth and development through BRI1-EMS-SUPPRESSOR1 (BES1)/BRASSINAZOLE-RESISTANT1 (BZR1) family transcription factors. Cotton (Gossypium hirsutum) fibers are highly elongated single cells, and BRs play a vital role in the regulation of fiber elongation. However, the mode of action on how BR is involved in the regulation of cotton fiber elongation remains unexplored. Here, we generated GhBES1.4 over expression lines and found that overexpression of GhBES1.4 promoted fiber elongation, whereas silencing of GhBES1.4 reduced fiber length. DNA affinity purification and sequencing (DAP-seq) identified 1,531 target genes of GhBES1.4, and five recognition motifs of GhBES1.4 were identified by enrichment analysis. Combined analysis of DAP-seq and RNA-seq data of GhBES1.4-OE/RNAi provided mechanistic insights into GhBES1.4-mediated regulation of cotton fiber development. Further, with the integrated approach of GWAS, RNA-seq, and DAP-seq, we identified seven genes related to fiber elongation that were directly regulated by GhBES1.4. Of them, we showed Cytochrome P450 84A1 (GhCYP84A1) and 3-hydroxy-3-methylglutaryl-coenzyme A reductase 1 (GhHMG1) promote cotton fiber elongation. Overall, the present study established the role of GhBES1.4-mediated gene regulation and laid the foundation for further understanding the mechanism of BR participation in regulating fiber development.
PMID: 36542688
Plant Physiol , IF:8.34 , 2023 Feb , V191 (2) : P1167-1185 doi: 10.1093/plphys/kiac568
Kinase regulators evolved into two families by gain and loss of ability to bind plant steroid receptors.
College of Life Sciences, Shaanxi Normal University, Xi'an 710119, Shaanxi Province, P.R. China.
All biological functions evolve by fixing beneficial mutations and removing deleterious ones. Therefore, continuously fixing and removing the same essential function to separately diverge monophyletic gene families sounds improbable. Yet, here we report that brassinosteroid insensitive1 kinase inhibitor1 (BKI1)/membrane-associated kinase regulators (MAKRs) regulating a diverse function evolved into BKI1 and MAKR families from a common ancestor by respectively enhancing and losing ability to bind brassinosteroid receptor brassinosteroid insensitive1 (BRI1). The BKI1 family includes BKI1, MAKR1/BKI1-like (BKL) 1, and BKL2, while the MAKR family contains MAKR2-6. Seedless plants contain only BKL2. In seed plants, MAKR1/BKL1 and MAKR3, duplicates of BKL2, gained and lost the ability to bind BRI1, respectively. In angiosperms, BKL2 lost the ability to bind BRI1 to generate MAKR2, while BKI1 and MAKR6 were duplicates of MAKR1/BKL1 and MAKR3, respectively. In dicots, MAKR4 and MAKR5 were duplicates of MAKR3 and MAKR2, respectively. Importantly, BKI1 localized in the plasma membrane, but BKL2 localized to the nuclei while MAKR1/BKL1 localized throughout the whole cell. Importantly, BKI1 strongly and MAKR1/BKL1 weakly inhibited plant growth, but BKL2 and the MAKR family did not inhibit plant growth. Functional study of the chimeras of their N- and C-termini showed that only the BKI1 family was partially reconstructable, supporting stepwise evolution by a seesaw mechanism between their C- and N-termini to alternately gain an ability to bind and inhibit BRI1, respectively. Nevertheless, the C-terminal BRI1-interacting motif best defines the divergence of BKI1/MAKRs. Therefore, BKI1 and MAKR families evolved by gradually gaining and losing the same function, respectively, extremizing divergent evolution and adding insights into gene (BKI1/MAKR) duplication and divergence.
PMID: 36494097
Plant Cell Environ , IF:7.228 , 2023 Apr , V46 (4) : P1249-1263 doi: 10.1111/pce.14502
Red-light receptor phytochrome B inhibits BZR1-NAC028-CAD8B signaling to negatively regulate rice resistance to sheath blight.
Department of Plant Pathology, College of Plant Protection, Shenyang Agricultural University, Shenyang, China.; Laboratory of Rice Disease Research, Institution of Plant Protection, Liaoning Academy of Agricultural Sciences, Shenyang, China.; Rice Research Institute, College of Agronomy, Shenyang Agricultural University, Shenyang, China.; Department of Plant Protection, Rice Research Institute, Sichuan Agricultural University, Chengdu, China.; Department of Biological Science, College of Life Science, Yan'an University, Yan'an, Shaanxi, China.; Liaoning Province Shiyan High School, Shenyang, China.; College of Biology and Food Engineering, Chongqing Three Gorges University, Chongqing, China.
Phytochrome (Phy)-regulated light signalling plays important roles in plant growth, development, and stress responses. However, its function in rice defence against sheath blight disease (ShB) remains unclear. Here, we found that PhyB mutation or shade treatment promoted rice resistance to ShB, while resistance was reduced by PhyB overexpression. Further analysis showed that PhyB interacts with phytochrome-interacting factor-like 15 (PIL15), brassinazole resistant 1 (BZR1), and vascular plant one-zinc-finger 2 (VOZ2). Plants overexpressing PIL15 were more susceptible to ShB in contrast to bzr1-D-overexpressing plants compared with the wild-type, suggesting that PhyB may inhibit BZR1 to negatively regulate rice resistance to ShB. Although BZR1 is known to regulate brassinosteroid (BR) signalling, the observation that BR signalling negatively regulated resistance to ShB indicated an independent role for BZR1 in controlling rice resistance. It was also found that the BZR1 ligand NAC028 positively regulated resistance to ShB. RNA sequencing showed that cinnamyl alcohol dehydrogenase 8B (CAD8B), involved in lignin biosynthesis was upregulated in both bzr1-D- and NAC028-overexpressing plants compared with the wild-type. Yeast-one hybrid, ChIP, and transactivation assays demonstrated that BZR1 and NAC028 activate CAD8B directly. Taken together, the analyses demonstrated that PhyB-mediated light signalling inhibits the BZR1-NAC028-CAD8B pathway to regulate rice resistance to ShB.
PMID: 36457051
Microbiol Spectr , IF:7.171 , 2023 Feb , V11 (1) : Pe0362122 doi: 10.1128/spectrum.03621-22
Duplicated Flagellins in Pseudomonas Divergently Contribute to Motility and Plant Immune Elicitation.
Key Laboratory of Microbial Resources Collection and Preservation, Ministry of Agriculture and Rural Affairs, Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing, China.; Department of Plant Pathology, China Agricultural University, Beijing, China.
Flagellins are the main constituents of the flagellar filaments that provide bacterial motility, chemotactic ability, and host immune elicitation ability. Although the functions of flagellins have been extensively studied in bacteria with a single flagellin-encoding gene, the function of multiple flagellin-encoding genes in a single bacterial species is largely unknown. Here, the model plant-growth-promoting bacterium Pseudomonas kilonensis F113 was used to decipher the divergent functions of duplicated flagellins. We demonstrate that the two flagellins (FliC-1 and FliC-2) in 12 Pseudomonas strains, including F113, are evolutionarily distinct. Only the fliC-1 gene but not the fliC-2 gene in strain F113 is responsible for flagellar biogenesis, motility, and plant immune elicitation. The transcriptional expression of fliC-2 was significantly lower than that of fliC-1 in medium and in planta, most likely due to variations in promoter activity. In silico prediction revealed that all fliC-2 genes in the 12 Pseudomonas strains have a poorly conserved promoter motif. Compared to the Flg22-2 epitope (relative to FliC-2), Flg22-1 (relative to FliC-1) induced stronger FLAGELLIN SENSING 2 (FLS2)-mediated microbe-associated molecular pattern-triggered immunity and significantly inhibited plant root growth. A change in the 19th amino acid in Flg22-2 reduced its binding affinity to the FLS2/brassinosteroid insensitive 1-associated kinase 1 complex. Also, Flg22-2 epitopes in the other 11 Pseudomonas strains were presumed to have low binding affinity due to the same change in the 19th amino acid. These findings suggest that Pseudomonas has evolved duplicate flagellins, with only FliC-1 contributing to motility and plant immune elicitation. IMPORTANCE Flagellins have emerged as important microbial patterns. This work focuses on flagellin duplication in some plant-associated Pseudomonas. Our findings on the divergence of duplicated flagellins provide a conceptual framework for better understanding the functional determinant flagellin and its peptide in multiple-flagellin plant-growth-promoting rhizobacteria.
PMID: 36629446
Plant J , IF:6.417 , 2023 Mar doi: 10.1111/tpj.16203
Brassinosteroid transcription factor BES1 modulates nitrate deficiency by promoting NRT2.1 and NRT2.2 transcription in Arabidopsis.
State Key Laboratory of Crop Stress Biology for Arid Areas, College of Natural Resources and Environment, Northwest A&F University, Yangling, Shaanxi, 712100, People's Republic of China.; High Latitude Crops Institute of Shanxi Agriculture University, Datong, Shanxi, 037008, People's Republic of China.; College of Life Sciences, Northwest A&F University, Yangling, Shaanxi, 712100, People's Republic of China.
Nitrogen (N) is one of the most essential mineral elements for plants. Brassinosteroids (BRs) play key roles in plant growth and development. Emerging evidence indicates that BRs participate in the responses to nitrate deficiency. However, the precise molecular mechanism underlying the BR signaling pathway in regulating nitrate deficiency remains largely unknown. The transcription factor BES1 regulates the expression of many genes in response to BRs. Root length, nitrate uptake, and N concentration of bes1-D mutants were higher than those of wild type under nitrate deficiency. BES1 levels strongly increased under low nitrate conditions, especially in the non-phosphorylated (active) form. Furthermore, BES1 directly bound to the promoters of NRT2.1 and NRT2.2 to promote their expression under nitrate deficiency. Taken together, BES1 is a key mediator that links BR signaling under nitrate deficiency by modulating high affinity nitrate transporters in plants.
PMID: 36948884
Plant J , IF:6.417 , 2023 Feb , V113 (3) : P460-477 doi: 10.1111/tpj.16058
Altered expression levels of long non-coding natural antisense transcripts overlapping the UGT73C6 gene affect rosette size in Arabidopsis thaliana.
Department of Molecular Signal Processing, Leibniz Institute of Plant Biochemistry, Halle/Saale, D-06120, Germany.; Section Microbial Biotechnology, Institute of Biochemistry and Biotechnology, Martin Luther University Halle-Wittenberg, Halle/Saale, D-06120, Germany.
Natural antisense long non-coding RNAs (lncNATs) are involved in the regulation of gene expression in plants, modulating different relevant developmental processes and responses to various stimuli. We have identified and characterized two lncNATs (NAT1(UGT73C6) and NAT2(UGT73C6) , collectively NATs(UGT73C6) ) from Arabidopsis thaliana that are transcribed from a gene fully overlapping UGT73C6, a member of the UGT73C subfamily of genes encoding UDP-glycosyltransferases (UGTs). Expression of both NATs(UGT73C6) is developmentally controlled and occurs independently of the transcription of UGT73C6 in cis. Downregulation of NATs(UGT73C6) levels through artificial microRNAs results in a reduction of the rosette area, while constitutive overexpression of NAT1(UGT73C6) or NAT2(UGT73C6) leads to the opposite phenotype, an increase in rosette size. This activity of NATs(UGT73C6) relies on its RNA sequence and, although modulation of UGT73C6 in cis cannot be excluded, the observed phenotypes are not a consequence of the regulation of UGT73C6 in trans. The NATs(UGT73C6) levels were shown to affect cell proliferation and thus individual leaf size. Consistent with this concept, our data suggest that the NATs(UGT73C6) influence the expression levels of key transcription factors involved in regulating leaf growth by modulating cell proliferation. These findings thus reveal an additional regulatory layer on the process of leaf growth. In this work, we characterized at the molecular level two long non-coding RNAs (NATs(UGT73C6) ) that are transcribed in the opposite direction to UGT73C6, a gene encoding a glucosyltransferase involved in brassinosteroid homeostasis in A. thaliana. Our results indicate that NATs(UGT73C6) expression influences leaf growth by acting in trans and by modulating the levels of transcription factors that are involved in the regulation of cell proliferation.
PMID: 36495314
Ecotoxicol Environ Saf , IF:6.291 , 2023 Feb , V251 : P114534 doi: 10.1016/j.ecoenv.2023.114534
Exogenous brassinosteroid alleviates calcium deficiency induced tip-burn by regulating calcium transport in Brassica rapa L. ssp. pekinensis.
College of Horticulture, Gansu Agricultural University, Lanzhou 730070, China.; College of Horticulture, Gansu Agricultural University, Lanzhou 730070, China; State Key Laboratory of Arid-land Crop Science, Gansu Agricultural University, Lanzhou 730070, China. Electronic address: hull@gsau.edu.cn.; College of Horticulture, Gansu Agricultural University, Lanzhou 730070, China; State Key Laboratory of Arid-land Crop Science, Gansu Agricultural University, Lanzhou 730070, China. Electronic address: yujihuagg@163.com.
Mini Chinese cabbage (Brassica rapa L. ssp. Pekinensis) plays an important role in the supply of summer vegetables on the plateau in western China. In recent years, tip-burn has seriously affected the yield, quality and commodity value of mini Chinese cabbage. Calcium (Ca(2+)) deficiency is a key inducer of tip-burn. As a new type plant hormone, brassinolide (BR) is involved in regulating a variety of biotic and abiotic stresses. To explore the alleviation role of BR in tip-burn caused by Ca(2+) deficiency, a hydroponic experiment was conducted to study the relationship between BR and Ca(2+) absorption and transport. The results showed that foliar spraying with 0.5 microM BR significantly reduced tip-burn incidence rate and disease index of mini Chinese cabbage caused by Ca(2+) deficiency. Moreover, the dynamic monitoring results of tip-burn incidence rate showed that the value reached the highest on the ninth day after treatment. BR promoted the Ca(2+) transport from roots to shoots and from outer leaves to inner leaves by increasing the activities of Ca(2+)-ATPase and H(+)-ATPase as well as the total ATP content, which provided power for Ca(2+) transport. In addition, exogenous BR upregulated the relative expression levels of BrACA4, BrACA11, BrECA1, BrECA3, BrECA4, BrCAX1, BrCAS and BrCRT2, whereas Ca(2+) deficiency induced down-regulation. In conclusion, exogenous BR can alleviate the Ca(2+)-deficiency induced tip-burn of mini Chinese cabbage by promoting the transport and distribution of Ca(2+).
PMID: 36646009
Sci China Life Sci , IF:6.038 , 2023 Mar doi: 10.1007/s11427-022-2319-0
Crosstalk between brassinosteroid signaling and variable nutrient environments.
Guangdong Laboratory for Lingnan Modern Agriculture, State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, College of Agriculture, South China Agricultural University, Guangzhou, 510642, China.; State Key Laboratory of Plant Genomics, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, 100101, China.; Key Laboratory for Enhancing Resource Use Efficiency of Crops in South China, Ministry of Agriculture and Rural Affairs, South China Agricultural University, Guangzhou, 510642, China.; National Key Facility for Crop Gene Resources and Genetic Improvement, Institute of Crop Sciences, Chinese Academy of Agricultural Sciences, Beijing, 100081, China. tonghongning@caas.cn.; Guangdong Laboratory for Lingnan Modern Agriculture, State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, College of Agriculture, South China Agricultural University, Guangzhou, 510642, China. ccchu@scau.edu.cn.; State Key Laboratory of Plant Genomics, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, 100101, China. ccchu@scau.edu.cn.; Key Laboratory for Enhancing Resource Use Efficiency of Crops in South China, Ministry of Agriculture and Rural Affairs, South China Agricultural University, Guangzhou, 510642, China. ccchu@scau.edu.cn.
Brassinosteroid (BR) represents a group of steroid hormones that regulate plant growth and development as well as environmental adaptation. The fluctuation of external nutrient elements is a situation that plants frequently face in the natural environment, in which nitrogen (N) and phosphorus (P) are two of the most critical nutrients restraint of the early growth of plants. As the macronutrients, N and P are highly required by plants, but their availability or solubility in the soil is relatively low. Since iron (Fe) and P always modulate each other's content and function in plants mutually antagonistically, the regulatory mechanisms of Fe and P are inextricably linked. Recently, BR has emerged as a critical regulator in nutrient acquisition and phenotypic plasticity in response to the variable nutrient levels in Arabidopsis and rice. Here, we review the current understanding of the crosstalk between BR and the three major nutrients (N, P, and Fe), highlighting how nutrient signaling regulates BR synthesis and signaling to accommodate plant growth and development in Arabidopsis and rice.
PMID: 36907968
Int J Mol Sci , IF:5.923 , 2023 Feb , V24 (5) doi: 10.3390/ijms24054614
Epi-Brassinolide Regulates ZmC4 NADP-ME Expression through the Transcription Factors ZmbHLH157 and ZmNF-YC2.
College of Life Science, Sichuan Agricultural University, Ya'an 625000, China.; State Key Laboratory of Crop Gene Exploration and Utilization in Southwest China, Sichuan Agricultural University, Chengdu 611130, China.; Maize Research Institute, Sichuan Agricultural University, Chengdu 611130, China.
Maize is a main food and feed crop with great production potential and high economic benefits. Improving its photosynthesis efficiency is crucial for increasing yield. Maize photosynthesis occurs mainly through the C4 pathway, and NADP-ME (NADP-malic enzyme) is a key enzyme in the photosynthetic carbon assimilation pathway of C4 plants. ZmC4-NADP-ME catalyzes the release of CO(2) from oxaloacetate into the Calvin cycle in the maize bundle sheath. Brassinosteroid (BL) can improve photosynthesis; however, its molecular mechanism of action remains unclear. In this study, transcriptome sequencing of maize seedlings treated with epi-brassinolide (EBL) showed that differentially expressed genes (DEGs) were significantly enriched in photosynthetic antenna proteins, porphyrin and chlorophyll metabolism, and photosynthesis pathways. The DEGs of C4-NADP-ME and pyruvate phosphate dikinase in the C4 pathway were significantly enriched in EBL treatment. Co-expression analysis showed that the transcription level of ZmNF-YC2 and ZmbHLH157 transcription factors was increased under EBL treatment and moderately positively correlated with ZmC4-NADP-ME. Transient overexpression of protoplasts revealed that ZmNF-YC2 and ZmbHLH157 activate C4-NADP-ME promoters. Further experiments showed ZmNF-YC2 and ZmbHLH157 transcription factor binding sites on the -1616 bp and -1118 bp ZmC4 NADP-ME promoter. ZmNF-YC2 and ZmbHLH157 were screened as candidate transcription factors mediating brassinosteroid hormone regulation of the ZmC4 NADP-ME gene. The results provide a theoretical basis for improving maize yield using BR hormones.
PMID: 36902048
Int J Mol Sci , IF:5.923 , 2023 Feb , V24 (4) doi: 10.3390/ijms24043631
Insights on Phytohormonal Crosstalk in Plant Response to Nitrogen Stress: A Focus on Plant Root Growth and Development.
State Key Laboratory of Conservation and Utilization of Subtropical Agro-Bioresources, Guangxi Key Laboratory of Sugarcane Biology, Guangxi University, Nanning 530004, China.; Department of Horticulture, Institute of Vegetable Science, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou 310058, China.; National Demonstration Center for Experimental Plant Science Education, College of Agriculture, Guangxi University, Nanning 530004, China.
Nitrogen (N) is a vital mineral component that can restrict the growth and development of plants if supplied inappropriately. In order to benefit their growth and development, plants have complex physiological and structural responses to changes in their nitrogen supply. As higher plants have multiple organs with varying functions and nutritional requirements, they coordinate their responses at the whole-plant level based on local and long-distance signaling pathways. It has been suggested that phytohormones are signaling substances in such pathways. The nitrogen signaling pathway is closely associated with phytohormones such as auxin (AUX), abscisic acid (ABA), cytokinins (CKs), ethylene (ETH), brassinosteroid (BR), strigolactones (SLs), jasmonic acid (JA), and salicylic acid (SA). Recent research has shed light on how nitrogen and phytohormones interact to modulate physiology and morphology. This review provides a summary of the research on how phytohormone signaling affects root system architecture (RSA) in response to nitrogen availability. Overall, this review contributes to identifying recent developments in the interaction between phytohormones and N, as well as serving as a foundation for further study.
PMID: 36835044
Int J Mol Sci , IF:5.923 , 2023 Feb , V24 (3) doi: 10.3390/ijms24032819
A Revised View of the LSU Gene Family: New Functions in Plant Stress Responses and Phytohormone Signaling.
Instituto de Bioquimica y Microbiologia, Facultad de Ciencias, Universidad Austral de Chile, Valdivia 5110566, Chile.; ANID-Millennium Science Initiative Program-Millennium Institute for Integrative Biology (iBio), Santiago 8331150, Chile.; Centro de Biotecnologia y Genomica de Plantas, INIA-CSIC-Universidad Politecnica de Madrid, 28223 Madrid, Spain.; Centro de Genomica y Bioinformatica, Facultad de Ciencias, Universidad Mayor, Santiago 8580745, Chile.; Escuela de Biotecnologia, Facultad de Ciencias, Universidad Mayor, Santiago 8580745, Chile.
LSUs (RESPONSE TO LOW SULFUR) are plant-specific proteins of unknown function that were initially identified during transcriptomic studies of the sulfur deficiency response in Arabidopsis. Recent functional studies have shown that LSUs are important hubs of protein interaction networks with potential roles in plant stress responses. In particular, LSU proteins have been reported to interact with members of the brassinosteroid, jasmonate signaling, and ethylene biosynthetic pathways, suggesting that LSUs may be involved in response to plant stress through modulation of phytohormones. Furthermore, in silico analysis of the promoter regions of LSU genes in Arabidopsis has revealed the presence of cis-regulatory elements that are potentially responsive to phytohormones such as ABA, auxin, and jasmonic acid, suggesting crosstalk between LSU proteins and phytohormones. In this review, we summarize current knowledge about the LSU gene family in plants and its potential role in phytohormone responses.
PMID: 36769138
Front Plant Sci , IF:5.753 , 2023 , V14 : P1104036 doi: 10.3389/fpls.2023.1104036
Proteome and phosphoproteome analysis of 2,4-epibrassinolide-mediated cold stress response in cucumber seedlings.
State Key Laboratory of Vegetable Biobreeding, Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Beijing, China.; Beijing Key Laboratory of Growth and Developmental Regulation for Protected Vegetable Tablecrops, China Agricultural University, Beijing, China.; College of Horticulture, Sichuan Agricultural University, Chengdu, China.; College of Horticulture, Zhejiang A & F University, Hangzhou, China.; College of Life Science, Gannan Normal University, Ganzhou, China.
The 2, 4-epibrassinolide (EBR) significantly increased plants cold tolerance. However, mechanisms of EBR in regulating cold tolerance in phosphoproteome and proteome levels have not been reported. The mechanism of EBR regulating cold response in cucumber was studied by multiple omics analysis. In this study, phosphoproteome analysis showed that cucumber responded to cold stress through multi-site serine phosphorylation, while EBR further upregulated single-site phosphorylation for most of cold-responsive phosphoproteins. Association analysis of the proteome and phosphoproteome revealed that EBR reprogrammed proteins in response to cold stress by negatively regulating protein phosphorylation and protein content, and phosphorylation negatively regulated protein content in cucumber. Further functional enrichment analysis of proteome and phosphoproteome showed that cucumber mainly upregulated phosphoproteins related to spliceosome, nucleotide binding and photosynthetic pathways in response to cold stress. However, different from the EBR regulation in omics level, hypergeometric analysis showed that EBR further upregulated 16 cold-up-responsive phosphoproteins participated photosynthetic and nucleotide binding pathways in response to cold stress, suggested their important function in cold tolerance. Analysis of cold-responsive transcription factors (TFs) by correlation between proteome and phosphoproteome showed that cucumber regulated eight class TFs may through protein phosphorylation under cold stress. Further combined with cold-related transcriptome found that cucumber phosphorylated eight class TFs, and mainly through targeting major hormone signal genes by bZIP TFs in response to cold stress, while EBR further increased these bZIP TFs (CsABI5.2 and CsABI5.5) phosphorylation level. In conclusion, the EBR mediated schematic of molecule response mechanisms in cucumber under cold stress was proposed.
PMID: 36895878
Theor Appl Genet , IF:5.699 , 2023 Mar , V136 (3) : P29 doi: 10.1007/s00122-023-04325-x
BnaC01.BIN2, a GSK3-like kinase, modulates plant height and yield potential in Brassica napus.
Crop Research Institute, Hunan Academy of Agricultural Sciences, Changsha, 410125, China.; Hunan Hybrid Rapeseed Engineering and Technology Research Center, Changsha, 410125, China.; Crop Research Institute, Hunan Academy of Agricultural Sciences, Changsha, 410125, China. limei1230@126.com.; Hunan Hybrid Rapeseed Engineering and Technology Research Center, Changsha, 410125, China. limei1230@126.com.; Crop Research Institute, Hunan Academy of Agricultural Sciences, Changsha, 410125, China. wangtonghua2014@163.com.; Hunan Hybrid Rapeseed Engineering and Technology Research Center, Changsha, 410125, China. wangtonghua2014@163.com.
Using map-based cloning and transgenic transformation, we revealed that glycogen kinase synthase 3-like kinase, BnaC01.BIN2, modulates plant height and yield in rapeseed. The modification of plant height is one of the most important goals in rapeseed breeding. Although several genes that regulate rapeseed plant height have been identified, the genetics mechanisms underlying rapeseed plant height regulation remain poorly understood, and desirable genetic resources for rapeseed ideotype breeding are scarce. Here, we map-based cloned and functionally verified that the rapeseed semi-dominant gene, BnDF4, greatly affects rapeseed plant height. Specifically, BnDF4 encodes brassinosteroid (BR)-insensitive 2, a glycogen synthase kinase 3 primarily expressed in the lower internodes to modulate rapeseed plant height by blocking basal internode-cell elongation. Transcriptome data showed that several cell expansion-related genes involving auxin and BRs pathways were significantly downregulated in the semi-dwarf mutant. Heterozygosity in the BnDF4 allele results in small stature with no marked differences in other agronomic traits. Using BnDF4 in the heterozygous condition, the hybrid displayed strong yield heterosis through optimum intermediate plant height. Our results provide a desirable genetic resource for breeding semi-dwarf rapeseed phenotypes and support an effective strategy for breeding rapeseed hybrid varieties with strong yield heterosis.
PMID: 36867248
Plant Sci , IF:4.729 , 2023 Mar , V331 : P111673 doi: 10.1016/j.plantsci.2023.111673
The receptor-like kinase EMS1 and BRI1 coordinately regulate stamen elongation via the transcription factors BES1/BZR1 in Arabidopsis.
College of Life Sciences, Shaanxi Normal University, Xi'an 710119, China.; College of Life Sciences, Shaanxi Normal University, Xi'an 710119, China. Electronic address: zhengbowen365@163.com.
Plants possess a large family of receptor kinase proteins to mediate cell-to-cell and cell-to-environment communication, and these regulations are essential for plant growth and development as well as resistance to biotic or abiotic stresses. EMS1 is a receptor kinase which involved in tapetum cell fate determination during anther development, while brassinosteroid (BR) receptor, BRI1, controls most aspects of plant growth and development. Although EMS1 and BRI1 are known to regulate independent biological processes, they interact with identical components of the downstream signaling pathways. However, the biological processes other than the tapetum development controlled by the EMS1 signal are not clear. Here, we report that EMS1 signaling-related mutants exhibited an insufficient stamen elongation phenotype, similar to BR signaling mutants. Transgenic expression of BRI1 restored the short filament phenotype of ems1. Conversely, co-expression of EMS1 and TPD1 also restored the short filaments of BRI1 mutants, bri1. Genetic experiments confirmed that EMS1 and BRI1 regulate filament elongation through their downstream transcription factors BES1/BZR1. Molecular analysis suggested that the decrease in BR signaling output in filaments of the ems1 mutant caused deficient filament development. Moreover, in vitro and in vivo experiments proved BES1 interacts with filament-specific transcription factor MYB21. Together, we found that the two receptor-like kinases (RLKs) EMS1 and BRI1 are cooperatively involved in the regulation of filament elongation via the transcription factors BES1/BZR1. These results indicated that the biological processes regulated by EMS1 and BRI1 in plants are both independent and interactive, which provides us with insights into multidimensional molecular control of the RLK pathway.
PMID: 36931564
Plant Cell Rep , IF:4.57 , 2023 Mar , V42 (3) : P587-598 doi: 10.1007/s00299-023-02981-3
Propiconazole-induced brassinosteroid deficiency reduces female fertility by inhibiting female gametophyte development in woodland strawberry.
Yokohama City University, Kihara Institute for Biological Research, Maioka 641-12, Totsuka, Yokohama, Kanagawa, 244-0813, Japan.; Advanced Instrumental Analysis Center, Teikyo University, 1-1 Toyosatodai, Utsunomiya, Tochigi, 321-8505, Japan.; Faculty of Agriculture, Utsunomiya University, 350 Mine, Utsunomiya, Tochigi, 321-8505, Japan.; Department of Biosciences, Teikyo University, 1-1 Toyosatodai, Utsunomiya, Tochigi, 320-8551, Japan.; Yokohama City University, Kihara Institute for Biological Research, Maioka 641-12, Totsuka, Yokohama, Kanagawa, 244-0813, Japan. aynakamu@yokohama-cu.ac.jp.
In woodland strawberry, a brassinosteroid biosynthesis inhibitor propiconazole induced typical brassinosteroid-deficient phenotypes and decreased female fertility due to attenuated female gametophyte development. Brassinosteroids (BRs) play roles in various aspects of plant development. We investigated the physiological roles of BRs in the woodland strawberry, Fragaria vesca. BR-level-dependent phenotypes were observed using a BR biosynthetic inhibitor, propiconazole (PCZ), and the most active natural BR, brassinolide (BL). Endogenous BL and castasterone, the active BRs, were below detectable levels in PCZ-treated woodland strawberry. The plants were typical BR-deficient phenotypes, and all phenotypes were restored by treatment with BL. These observations indicate that PCZ is an effective inhibitor of BR in woodland strawberry. Only one gene for each major step of BR biosynthesis in Arabidopsis is encoded in the woodland strawberry genome. BR biosynthetic genes are highly expressed during the early stage of fruit development. Emasculated flowers treated with BL failed to develop fruit, implying that BR is not involved in parthenocarpic fruit development. Similar to BR-deficient and BR-insensitive Arabidopsis mutants, female fertility was lower in PCZ-treated plants than in mock-treated plants due to failed attraction of the pollen tube to the ovule. In PCZ-treated plants, expression of FveMYB98, the homologous gene for Arabidopsis MYB98 (a marker for synergid cells), was downregulated. Ovules were smaller in PCZ-treated plants than in mock-treated plants, and histological analysis implied that the development of more than half of female gametophytes was arrested at the early stage in PCZ-treated plants. Our findings explain how BRs function during female gametophyte development in woodland strawberry.
PMID: 36629883
Physiol Plant , IF:4.5 , 2023 Feb : Pe13875 doi: 10.1111/ppl.13875
Transcriptome analysis of drought-responsive and drought-tolerant mechanisms in maize leaves under drought stress.
Jilin Engineering Research Center for Crop Biotechnology Breeding, College of Plant Science, Jilin University, Changchun, China.
Maize is a major crop essential for food and feed, but its production is threatened by various biotic and abiotic stresses. Drought is one of the most common abiotic stresses, causing severe crop yield reduction. Although several studies have been devoted to selecting drought-tolerant maize lines and detecting the drought-responsive mechanism of maize, the transcriptomic differences between drought-tolerant and drought-susceptible maize lines are still largely unknown. In our study, RNA-seq was performed on leaves of the drought-tolerant line W9706 and the drought-susceptible line B73 after drought treatment. We identified 3147 differentially expressed genes (DEGs) between these two lines. The up-regulated DEGs in W9706 were enriched in specific processes, including ABA signaling, wax biosynthesis, CHO metabolism, signal transduction and brassinosteroid biosynthesis-related processes, while the downregulated DEGs were enriched in specific processes, such as stomatal movement. Altogether, transcriptomic analysis suggests that the different drought resistances were correlated with the differential expression of genes, while the drought tolerance of W9706 is due to the more rapid response to stimulus, higher water retention capacity and stable cellular environment under water deficit conditions. This article is protected by copyright. All rights reserved.
PMID: 36775906
Plant Physiol Biochem , IF:4.27 , 2023 Feb , V196 : P993-1001 doi: 10.1016/j.plaphy.2023.02.052
Grape cytochrome P450 CYP90D1 regulates brassinosteroid biosynthesis and increases vegetative growth.
Laboratory of Fruit Genetic Engineering, The Institute of Enology and Viticulture, University of Yamanashi, 1-13-1 Kofu, Yamanashi, 400-0005, Japan. Electronic address: senoki@yamanashi.ac.jp.; NODAI Genome Research Center, Tokyo University of Agriculture, 1-1-1 Setagaya, Tokyo, 156-8502, Japan.; Laboratory of Fruit Genetic Engineering, The Institute of Enology and Viticulture, University of Yamanashi, 1-13-1 Kofu, Yamanashi, 400-0005, Japan.
Vine vigor or vegetative growth is an important factor related to berry quality and vinicultural training management, but brassinosteroid (BR)-induced molecular mechanisms underlying vine growth remain unclear. In this study, the hypothesis that the Vitis vinifera CYP90D1 gene VvCYP90D1, one of the genes for BR biosynthesis, plays a critical role in shoot elongation was tested. RNA sequencing analysis of shoots collected from the vigorous cultivar Koshu (KO) and the reference cultivar Pinot Noir (PN) 7 days after bud break showed higher expression levels of various genes in the BR biosynthesis pathway in KO than in PN. The VvCYP90D1 expression level in KO was highest in meristems, followed by internodes and leaves. Cluster analysis of amino acid sequences including those in other plant species showed that the isolated gene belonged to the CYP90D1 group. The vegetative growth and the endogenous BR (brassinolide; BL) content were significantly higher in VvCYP90D1-overexpressing Arabidopsis than in wild type. VvCYP90D1-overexpressing Arabidopsis treated with brassinazole (Brz), a BR biosynthesis inhibitor, showed recovery of vegetative growth. These results indicate that VvCYP90D1 in grapevine has a vegetative growth promoting effect via BR biosynthesis. Our findings on the mechanism of BR-induced grape shoot growth will contribute to the development of new shoot control techniques for grapevine.
PMID: 36898216
Plant Physiol Biochem , IF:4.27 , 2023 Jan , V196 : P281-290 doi: 10.1016/j.plaphy.2023.01.056
Cadmium treatment induces endoplasmic reticulum stress and unfolded protein response in Arabidopsisthaliana.
Institute of Sciences of Food Production, C.N.R., Unit of Lecce, Lecce, Italy.; Laboratory of General and Inorganic Chemistry, Di.S.Te.B.A. (Dipartimento di Scienze e Technologie Biologic e Ambientali), University of Salento, Lecce, Italy.; Institute of Agricultural Biology and Biotechnology, C.N.R., Unit of Milan, Milano, Italy; Leicester Institute of Structural and Chemical Biology, Department of Molecular and Cell Biology, University of Leicester, Leicester, UK.; Institute of Sciences of Food Production, C.N.R., Unit of Lecce, Lecce, Italy. Electronic address: angelo.santino@ispa.cnr.it.
We report about the response of Arabidopsis thaliana to chronic and temporary Cd(2+) stress, and the Cd(2+) induced activation of ER stress and unfolded protein response (UPR). Cd(2+)-induced UPR proceeds mainly through the bZIP60 arm, which in turn activates relevant ER stress marker genes such as BiP3, CNX, PDI5 and ERdj3B in a concentration- (chronic stress) or time- (temporary stress) dependent manner. A more severe Cd-stress triggers programmed cell death (PCD) through the activation of the NAC089 transcription factor. Toxic effects of Cd(2+) exposure are reduced in the Atbzip28/bzip60 double mutant in terms of primary root length and fresh shoot weight, likely due to reduced UPR and PCD activation. We also hypothesised that the enhanced Cd(2+) tolerance of the Atbzip28/bzip60 double mutant is due to an increase in brassinosteroids signaling, since the amount of the brassinosteroid insensitive1 receptor (BRI1) protein decreases under Cd(2+) stress only in Wt plants. These data highlight the complexity of the UPR pathway, since the ER stress response is strictly related to the type of the treatment applied and the multifaceted connections of ER signaling. The reduced sensing of Cd(2+) stress in plants with UPR defects can be used as a novel strategy for phytoremediation.
PMID: 36736010
Plant Physiol Biochem , IF:4.27 , 2023 Feb , V195 : P163-169 doi: 10.1016/j.plaphy.2023.01.007
Light induction of somatic embryogenesis in Arabidopsis is regulated by PHYTOCHROME E.
Department of Plant Science, University of Manitoba, Winnipeg, R3T2N2, Canada.; Department of Plant Science, University of Manitoba, Winnipeg, R3T2N2, Canada. Electronic address: Claudio.stasolla@umanitoba.ca.
The requirement of light on somatic embryogenesis (SE) has been documented in many species; however, no mechanism of action has been elucidated. Using Arabidopsis SE as a model, the effect of red light (660 nm) during the induction phase corresponding to the formation of the embryogenic tissue was examined. Analyses of several phytochrome mutants revealed that red light signaling, conducive to SE, was mediated by PHYTOCHROME E (PHYE). Both phyE and darkness were sufficient to repress the formation of somatic embryos and reduced the expression of CONSTITUTIVE PHOTOMORPHIC DWARF 3 (CPD3), a rate limiting step in brassinosteroid (BR) biosynthesis, as well as AGAMOUS LIKE 15 (AGL15), a key inducer of many SE genes. We further integrated BR signaling and nitric oxide (NO) with PHYE by demonstrating that applications of both compounds to phyE explants and WT explants cultured in the dark partially restored AGL15 expression. These results demonstrate that SE induction by red light operates via PHYE through BR signaling and NO required to induce AGL15.
PMID: 36640683
BMC Plant Biol , IF:4.215 , 2023 Feb , V23 (1) : P64 doi: 10.1186/s12870-023-04050-z
Transcriptome analysis reveals the key pathways and candidate genes involved in salt stress responses in Cymbidium ensifolium leaves.
The First Affiliated Hospital of Yunnan University of Traditional Chinese Medicine, 650021, Kunming, China.; Key Laboratory for Forest Resources Conservation and Utilization in the Southwest Mountains of China, Ministry of Education, Southwest Forestry University, 650224, Kunming, China.; Yunnan Key Laboratory of Plateau Wetland Conservation, Restoration and Ecological Services, Southwest Forestry University, 650224, Kunming, China.; Department of Life Technology Teaching and Research, School of Life Science, Southwest Forestry University, 650224, Kunming, China.; Faculty of Mathematics and Physics, Southwest Forestry University, 650224, Kunming, China.; CIRAD, UMR AGAP Institute, F-34398, Montpellier, France.; The First Affiliated Hospital of Yunnan University of Traditional Chinese Medicine, 650021, Kunming, China. 1820059756@qq.com.; Key Laboratory for Forest Resources Conservation and Utilization in the Southwest Mountains of China, Ministry of Education, Southwest Forestry University, 650224, Kunming, China. 1820059756@qq.com.
BACKGROUND: Cymbidium ensifolium L. is known for its ornamental value and is frequently used in cosmetics. Information about the salt stress response of C. ensifolium is scarce. In this study, we reported the physiological and transcriptomic responses of C. ensifolium leaves under the influence of 100 mM NaCl stress for 48 (T48) and 96 (T96) hours. RESULTS: Leaf Na(+) content, activities of the antioxidant enzymes i.e., superoxide dismutase, glutathione S-transferase, and ascorbate peroxidase, and malondialdehyde content were increased in salt-stressed leaves of C. ensifolium. Transcriptome analysis revealed that a relatively high number of genes were differentially expressed in CKvsT48 (17,249) compared to CKvsT96 (5,376). Several genes related to salt stress sensing (calcium signaling, stomata closure, cell-wall remodeling, and ROS scavenging), ion balance (Na(+) and H(+)), ion homeostasis (Na(+)/K(+) ratios), and phytohormone signaling (abscisic acid and brassinosteroid) were differentially expressed in CKvsT48, CKvsT96, and T48vsT96. In general, the expression of genes enriched in these pathways was increased in T48 compared to CK while reduced in T96 compared to T48. Transcription factors (TFs) belonging to more than 70 families were differentially expressed; the major families of differentially expressed TFs included bHLH, NAC, MYB, WRKY, MYB-related, and C3H. A Myb-like gene (CenREV3) was further characterized by overexpressing it in Arabidopsis thaliana. CenREV3's expression was decreased with the prolongation of salt stress. As a result, the CenREV3-overexpression lines showed reduced root length, germination %, and survival % suggesting that this TF is a negative regulator of salt stress tolerance. CONCLUSION: These results provide the basis for future studies to explore the salt stress response-related pathways in C. ensifolium.
PMID: 36721093
Tree Physiol , IF:4.196 , 2023 Feb doi: 10.1093/treephys/tpad022
Transcriptional reprogramming during recovery from drought stress in Eucalyptus grandis.
Department of Biochemistry, Genetics and Microbiology, Forestry and Agricultural Biotechnology Institute (FABI), University of Pretoria, Pretoria, South Africa.; Department of Agriculture, University of Zululand, KwaDlangezwa, South Africa.; Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA.
The importance of drought as a constraint to agriculture and forestry is increasing with climate change. Genetic improvement of plants' resilience is one of the mitigation strategies to curb this threat. Although recovery from drought stress is important to long term drought adaptation and has been considered as an indicator of dehydration tolerance in annual crops, this has not been well-explored in forest trees. Thus, we aimed to investigate the physiological and transcriptional changes during drought stress and rewatering in Eucalyptus grandis. We set up a greenhouse experiment where we imposed drought stress on two-year-old seedlings and rewatered the recovery group after 17 days of drought. Our measurement of leaf stomatal conductance (gs) showed that, while gs was reduced by drought stress, it fully recovered after 5 days of rewatering. RNA-seq analysis from stem samples revealed that genes related to known stress responses such as phytohormone and reactive oxygen species signaling were upregulated while genes involved in metabolism and growth were downregulated due to drought stress. We observed reprogramming of signal transduction pathways and metabolic processes at 1 day of rewatering, indicating a quick response to rewatering. Our results suggest that recovery from drought stress may entail alterations in the jasmonic acid, salicylic acid, ethylene, and brassinosteroid signaling pathways. Using co-expression network analysis, we identified hub genes including the putative orthologs of ABI1, ABF2, ABF3, HAI2, BAM1, GolS2, and SIP1 during drought and CAT2, G6PD1, ADG1, and FD-1 during recovery. Taken together, by highlighting the molecular processes and identifying key genes, this study gives an overview of the mechanisms underlying the response of E. grandis to drought stress and recovery that trees may face repeatedly throughout their long-life cycle. This provides a useful reference to the identification and further investigation of signaling pathways and target genes for future tree improvement.
PMID: 36851855
Planta , IF:4.116 , 2023 Feb , V257 (3) : P48 doi: 10.1007/s00425-023-04086-3
Insights on the stem elongation of spur-type bud sport mutant of 'Red Delicious' apple.
College of Horticulture, Gansu Agricultural University, Lanzhou, 730070, China.; College of Bioengineering and Biotechnology, Tianshui Normal University, Tianshui, 741000, China.; College of Horticulture, Gansu Agricultural University, Lanzhou, 730070, China. bhch@gsau.edu.cn.
The decreased capacity of auxin-, CTK-, and BR-mediated cell division and cell enlargement pathways, combined with the enhanced capacity of GA and ETH-, JA-, ABA-, SA-mediated stress-resistant pathways were presumed to be the crucial reasons for the formation of spur-type 'Red Delicious' mutants. Vallee Spur', which exhibit short internodes and compact tree shape, is the fourth generation of the spur-type bud sport mutant of 'Red Delicious'. However, the underlying molecular mechanism of these properties remains unclear. Here, comparative phenotypic, full-length transcriptome and phytohormone analyses were performed between 'Red Delicious' (NSP) and 'Vallee Spur' (SP). The new shoot internode length of NSP was > 1.53-fold higher than that of the SP mutant. Cytological analysis showed that the stem cells of the SP mutant were smaller and more tightly arranged relative to the NSP. By Iso-Seq, a total of 1426 differentially expressed genes (DEGs) were detected, including 808 upregulated and 618 downregulated genes in new shoot apex with 2 leaves of the SP mutant. Gene expressions involved in auxin, cytokinin (CTK), and brassinosteroid (BR) signal transduction were mostly downregulated in the SP mutant, whereas those involved in gibberellin (GA), ethylene (ETH), jasmonate (JA), ABA, and salicylic acid (SA) signal transduction were mostly upregulated. The overall thermogram analysis of hormone levels in the shoot apex carrying two leaves detected by LC-MS/MS absolute quantification showed that the levels of IAA-Asp, IAA, iP7G, OPDA, and 6-deoxyCS were significantly upregulated in the SP mutant, while the remaining 28 hormones were significantly downregulated. It is speculated that the decreased capacity of auxin, CTK, and BR-mediated cell division and cell enlargement pathways is crucial for the formation of the SP mutant. GA and stress-resistant pathways of ETH, JA, ABA, and SA also play vital roles in stem elongation. These results highlight the involvement of phytohormones in the formation of stem elongation occurring in 'Red Delicious' spur-type bud sport mutants and provide information for exploring its biological mechanism.
PMID: 36740622
BMC Genomics , IF:3.969 , 2023 Feb , V24 (1) : P65 doi: 10.1186/s12864-023-09151-5
Transcriptome analysis of Citrus limon infected with Citrus yellow vein clearing virus.
Citrus Research Institute, Southwest University, Beibei, Chongqing, 400712, China.; Citrus Research Institute, Southwest University, Beibei, Chongqing, 400712, China. songzhen@cric.cn.; Citrus Research Institute, Southwest University, Beibei, Chongqing, 400712, China. zhoucy@cric.cn.
BACKGROUND: Citrus yellow vein clearing virus (CYVCV) is the causative agent of citrus yellow vein clearing disease, and poses a serious threat to the lemon industry in Asia. The common symptoms of CYVCV-infected lemon plants are leaf crinkling, leaf chlorotic mottling, and yellow vein clearing. However, the molecular mechanisms underlying CYVCV-citrus interaction that responsible for symptom occurrence is still unclarified. In this study, RNA-seq was performed to analyze the gene expression patterns of 'Eureka' lemon (Citrus limon Burm. f.) plants in response to CYVCV infection. RESULTS: There were 3691 differentially expressed genes (DEGs) identified by comparison between mock and CYVCV-infected lemon plants through RNA-seq. Bioinformatics analyses revealed that these DEGs were components of different pathways involved in phenylpropanoid biosynthesis, brassinosteroid biosynthesis, flavonoid biosynthesis and photosynthesis. Among these, the DEGs related to phytohormone metabolism and photosynthesis pathways were further enriched and analyzed. This study showed that different phytohormone-related genes had different responses toward CYVCV infection, however almost all of the photosynthesis-related DEGs were down-regulated in the CYVCV-infected lemon plants. The obtained RNA-seq data were validated by RT-qPCR using 12 randomly chosen genes, and the results of mRNA expression analysis were consistent with those of RNA-seq. CONCLUSIONS: The phytohormone biosynthesis, signaling and photosynthesis-related genes of lemon plants were probably involved in systemic infection and symptom occurrence of CYVCV. Notably, CYVCV infection had regulatory effects on the biosynthesis and signaling of phytohormone, which likely improve systemic infection of CYVCV. Additionally, CYVCV infection could cause structural changes in chloroplast and inhibition of photosynthesis pathway, which probably contribute to the appearance of leaf chlorotic mottling and yellow vein clearing in CYVCV-infected lemon plants. This study illustrates the dynamic nature of the citrus-CYVCV interaction at the transcriptome level and provides new insights into the molecular mechanism underlying the pathogenesis of CYVCV in lemon plants.
PMID: 36750773
Plants (Basel) , IF:3.935 , 2023 Mar , V12 (6) doi: 10.3390/plants12061290
Integrative Analysis of Transcriptome, Proteome, and Phosphoproteome Reveals Potential Roles of Photosynthesis Antenna Proteins in Response to Brassinosteroids Signaling in Maize.
Institute of Quality Standard and Testing Technology Research, Sichuan Academy of Agricultural Sciences, Chengdu 611130, China.; College of Life Science, Sichuan Agricultural University, Ya'an 625014, China.
Brassinosteroids are a recently discovered group of substances that promote plant growth and productivity. Photosynthesis, which is vital for plant growth and high productivity, is strongly influenced by brassinosteroid signaling. However, the molecular mechanism underlying the photosynthetic response to brassinosteroid signaling in maize remains obscure. Here, we performed integrated transcriptome, proteome, and phosphoproteomic analyses to identify the key photosynthesis pathway that responds to brassinosteroid signaling. Transcriptome analysis suggested that photosynthesis antenna proteins and carotenoid biosynthesis, plant hormone signal transduction, and MAPK signaling in CK VS EBR and CK VS Brz were significantly enriched in the list of differentially expressed genes upon brassinosteroids treatment. Consistently, proteome and phosphoproteomic analyses indicated that photosynthesis antenna and photosynthesis proteins were significantly enriched in the list of differentially expressed proteins. Thus, transcriptome, proteome, and phosphoproteome analyses showed that major genes and proteins related to photosynthesis antenna proteins were upregulated by brassinosteroids treatment in a dose-dependent manner. Meanwhile, 42 and 186 transcription factor (TF) responses to brassinosteroid signals in maize leaves were identified in the CK VS EBR and CK VS Brz groups, respectively. Our study provides valuable information for a better understanding of the molecular mechanism underlying the photosynthetic response to brassinosteroid signaling in maize.
PMID: 36986978
Life (Basel) , IF:3.817 , 2023 Feb , V13 (2) doi: 10.3390/life13020498
Interplay Impact of Exogenous Application of Abscisic Acid (ABA) and Brassinosteroids (BRs) in Rice Growth, Physiology, and Resistance under Sodium Chloride Stress.
State Key Laboratory of Rice Biology, China National Rice Research Institute, Hangzhou 310006, China.; Soil and Water Testing Laboratory, Marketing Division, Pak Arab Fertilizer Limited, Multan 66000, Pakistan.; MS Swaminathan School of Agriculture, Centurion University of Technology and Management, Paralakhemundi 761211, India.; Department of Soil Science, Bahauddin Zakariya University, Multan 60700, Pakistan.; Department of Soil Science, Faculty of Agricultural Sciences, Quid-E-Azam Campus, University of the Punjab, Lahore 54590, Pakistan.; Department of Plant Pathology, Agricultural College, Guizhou University, Guiyang 550001, China.
The hormonal imbalances, including abscisic acid (ABA) and brassinosteroid (BR) levels, caused by salinity constitute a key factor in hindering spikelet development in rice and in reducing rice yield. However, the effects of ABA and BRs on spikelet development in plants subjected to salinity stress have been explored to only a limited extent. In this research, the effect of ABA and BRs on rice growth characteristics and the development of spikelets under different salinity levels were investigated. The rice seedlings were subjected to three different salt stress levels: 0.0875 dS m(-1) (Control, CK), low salt stress (1.878 dS m(-1), LS), and heavy salt stress (4.09 dS m(-1), HS). Additionally, independent (ABA or BR) and combined (ABA+BR) exogenous treatments of ABA (at 0 and 25 muM concentration) and BR (at 0 and 5 muM concentration) onto the rice seedlings were performed. The results showed that the exogenous application of ABA, BRs, and ABA+BRs triggered changes in physiological and agronomic characteristics, including photosynthesis rate (Pn), SPAD value, pollen viability, 1000-grain weight (g), and rice grain yield per plant. In addition, spikelet sterility under different salt stress levels (CK, LS, and HS) was decreased significantly through the use of both the single phytohormone and the cocktail, as compared to the controls. The outcome of this study reveals new insights about rice spikelet development in plants subjected to salt stress and the effects on this of ABA and BR. Additionally, it provides information on the use of plant hormones to improve rice yield under salt stress and on the enhancement of effective utilization of salt-affected soils.
PMID: 36836855
Gene , IF:3.688 , 2023 Feb , V854 : P147059 doi: 10.1016/j.gene.2022.147059
Grape BES1 transcription factor gene VvBES1-3 confers salt tolerance in transgenic Arabidopsis.
College of Horticulture, Gansu Agricultural University, Lanzhou 730070, China.; College of Horticulture, Gansu Agricultural University, Lanzhou 730070, China. Electronic address: bhch@gsau.edu.cn.
BRI1-EMS-Suppressor 1 (BES1) regulates plant growth, development, and stress resistance, and plays a pivotal role in the brassinosteroid (BR) signal transduction pathway. In this study, a total of 12 BES1 genes were identified in the grape (Vitis vinifera) genome. Phylogenetic, structure, and motif sequence analyses of these genes provided insights into their evolutionary characteristics. Hormone-, stress-, and light-responsive and organ-specific cis-acting elements were identified in VvBES1 gene promoters. Microarray data analysis showed that VvBES1 family members exhibit diverse expression patterns in different organs. Quantitative real-time PCR (qRT-PCR) analysis showed that the expression levels of VvBES1 genes differed in response to BR, methyl jasmonate (MeJA), cold (4 degrees C), NaCl, and polyethylene glycol (PEG) treatments. The expression of VvBES1-3 was 29-fold higher under salt stress than control at 12 h. Moreover, VvBES1-3-overexpessing Arabidopsis thaliana plants showed lower malondialdehyde content, higher proline content, enhanced antioxidant enzyme (catalase, superoxide dismutase, peroxidase) activities, and higher salt-responsive gene expression levels than wild-type plants under salt stress, indicating that VvBES1-3 overexpression enhances salt stress tolerance in transgenic Arabidopsis. These results will contribute to further understanding the functions of BES1 transcription factors in the abiotic stress response.
PMID: 36535462
Steroids , IF:2.668 , 2023 Feb , V190 : P109153 doi: 10.1016/j.steroids.2022.109153
Cancer and brassinosteroids: Mechanisms of action, SAR and future perspectives.
Instituto de Quimica y Bioquimica, Facultad de Ciencias, Universidad de Valparaiso, Av. Gran Bretana 1111, Valparaiso 2360102, Chile. Electronic address: marcos.lorcac@alumnos.uv.cl.; Instituto de Quimica y Bioquimica, Facultad de Ciencias, Universidad de Valparaiso, Av. Gran Bretana 1111, Valparaiso 2360102, Chile. Electronic address: david.cabezas@postgrado.uv.cl.; Instituto de Quimica y Bioquimica, Facultad de Ciencias, Universidad de Valparaiso, Av. Gran Bretana 1111, Valparaiso 2360102, Chile. Electronic address: ileana.araque@postgrado.uv.cl.; Instituto de Quimica y Bioquimica, Facultad de Ciencias, Universidad de Valparaiso, Av. Gran Bretana 1111, Valparaiso 2360102, Chile. Electronic address: andres.teran@postgrado.uv.cl.; Instituto de Quimica y Bioquimica, Facultad de Ciencias, Universidad de Valparaiso, Av. Gran Bretana 1111, Valparaiso 2360102, Chile. Electronic address: santiago.hernandez@postgrado.uv.cl.; Instituto de Investigacion y Postgrado, Facultad de Ciencias de la Salud, Universidad Central de Chile, Santiago 8330507, Chile. Electronic address: marco.mellado@ucentral.cl.; Departamento de Quimica, Universidad Tecnica Federico Santa Maria, Av. Espana No. 1680, Valparaiso 2340000, Chile. Electronic address: luis.espinozac@usm.cl.; Instituto de Quimica y Bioquimica, Facultad de Ciencias, Universidad de Valparaiso, Av. Gran Bretana 1111, Valparaiso 2360102, Chile; Centro de Investigacion Farmacopea Chilena (CIFAR), Universidad de Valparaiso, Av. Gran Bretana 1111, Valparaiso 2360102, Chile. Electronic address: jaime.mella@uv.cl.
Brassinosteroids are plant hormones whose main function is to stimulate plant growth. However, they have been studied for their biological applications in humans. Brassinosteroid compounds have displayed an important role in the study of cancer pathology and show potential for developing novel anticancer drugs. In this review we describe the relationship of brassinosteroids with cancer with focus on the last decade, the mechanisms of cytotoxic activity described to date, and a structure-activity relationship based on the available information.
PMID: 36481216
Plant Signal Behav , IF:2.247 , 2023 Dec , V18 (1) : P2163337 doi: 10.1080/15592324.2022.2163337
Arabidopsis clathrin adaptor EPSIN1 but not MODIFIED TRANSPORT TO THE VACOULE1 contributes to effective plant immunity against pathogenic Pseudomonas bacteria.
University of Missouri-Columbia, Division of Biochemistry, Interdisciplinary Plant Group (IPG), Columbia, MO, USA.; Department of Plant Physiology, University of Potsdam, Potsdam, Germany.
In eukaryotes, EPSINs are Epsin N-terminal Homology (ENTH) domain-containing proteins that serve as monomeric clathrin adaptors at the plasma membrane (PM) or the trans-Golgi Network (TGN)/early endosomes (EE). The model plant Arabidopsis thaliana encodes for seven ENTH proteins, of which so far, only AtEPSIN1 (AtEPS1) and MODIFIED TRANSPORT TO THE VACUOLE1 (AtMTV1) localize to the TGN/EE and contribute to cargo trafficking to both the cell surface and the vacuole. However, relatively little is known about role(s) of any plant EPSIN in governing physiological responses. We have recently shown that AtEPS1 is a positive modulator of plant immune signaling and pattern-triggered immunity against flagellated Pseudomonas syringae pv. tomato (Pto) DC3000 bacteria. In eps1 mutants, impaired immune responses correlate with reduced accumulation of the receptor FLAGELLIN SENSING2 (AtFLS2) and the convergent immune co-receptor BRASSINOSTEROID INSENTIVE1-ASSOCIATED RECEPTOR KINASE1 (AtBAK1) in the PM. Here, we report that in contrast to AtEPS1, the TGN/EE-localized AtMTV1 did not contribute significantly to immunity against pathogenic Pto DC3000 bacteria. We also compared the amino acid sequences, peptide motif structures and in silico tertiary structures of the ENTH domains of AtEPS1 and AtMTV1 in more detail. We conclude that despite sharing the classical tertiary alpha helical ENTH-domain structure and clathrin-binding motifs, the overall low amino acid identity and differences in peptide motifs may explain their role(s) in trafficking of some of the same as well as distinct cargo components to their site of function, with the latter potentially contributing to differences in physiological responses.
PMID: 36603596
J Genet Genomics , 2023 Mar doi: 10.1016/j.jgg.2023.03.004
Brassinosteroid signaling and molecular crosstalk with nutrients in plants.
The Key Laboratory of Plant Development and Environmental Adaptation Biology, Ministry of Education, School of Life Sciences, Shandong University, Qingdao, Shandong 266237, China.; The Key Laboratory of Plant Development and Environmental Adaptation Biology, Ministry of Education, School of Life Sciences, Shandong University, Qingdao, Shandong 266237, China. Electronic address: baimingyi@sdu.edu.cn.
As sessile organisms, plants have evolved sophisticated mechanisms to optimize their growth and development in response to fluctuating nutrient levels. Brassinosteroids (BRs) are a group of plant steroid hormones that play critical roles in plant growth and developmental processes as well as plant responses to environmental stimuli. Recently, multiple molecular mechanisms have been proposed to explain the integration of BRs with different nutrient signaling processes to coordinate gene expression, metabolism, growth, and survival. Here, we review recent advances in understanding the molecular regulatory mechanisms of the BR signaling pathway and the multifaceted roles of BR in the intertwined sensing, signaling, and metabolic processes of sugar, nitrogen, phosphorus, and iron. Further understanding and exploring these BR-related processes and mechanisms will facilitate advances in crop breeding for higher resource efficiency.
PMID: 36914050
Plant Commun , 2023 Mar , V4 (2) : P100450 doi: 10.1016/j.xplc.2022.100450
The U-box ubiquitin ligase TUD1 promotes brassinosteroid-induced GSK2 degradation in rice.
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, Institute of Genetics and Developmental Biology, The Innovative Academy for Seed Design, Chinese Academy of Sciences, Beijing 100101, China.; National Key Facility for Crop Gene Resources and Genetic Improvement, Institute of Crop Sciences, Chinese Academy of Agricultural Sciences, Beijing 100081, China; National Nanfan Research Institute, Chinese Academy of Agricultural Sciences, Sanya 572024, China. Electronic address: tonghongning@caas.cn.
Brassinosteroids (BRs) are a class of steroid hormones with great potential for use in crop improvement. De-repression is usually one of the key events in hormone signaling. However, how the stability of GSK2, the central negative regulator of BR signaling in rice (Oryza sativa), is regulated by BRs remains elusive. Here, we identify the U-box ubiquitin ligase TUD1 as a GSK2-interacting protein by yeast two-hybrid screening. We show that TUD1 is able to directly interact with GSK2 and ubiquitinate the protein. Phenotypes of the tud1 mutant are highly similar to those of plants with constitutively activated GSK2. Consistent with this finding, GSK2 protein accumulates in the tud1 mutant compared with the wild type. In addition, inhibition of BR synthesis promotes GSK2 accumulation and suppresses TUD1 stability. By contrast, BRs can induce GSK2 degradation but promote TUD1 accumulation. Furthermore, the GSK2 degradation process is largely impaired in tud1 in response to BR. In conclusion, our study demonstrates the role of TUD1 in BR-induced GSK2 degradation, thereby advancing our understanding of a critical step in the BR signaling pathway of rice.
PMID: 36127877