Mol Plant , IF:13.164 , 2022 Feb , V15 (2) : P293-307 doi: 10.1016/j.molp.2021.09.010
A cryptic inhibitor of cytokinin phosphorelay controls rice grain size.
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.; 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.; Biogle Genome Editing Center, Changzhou, Jiangsu Province 213125, China.; Department of Genetics, Development and Cell Biology, Iowa State University, Ames, IA 50011, USA.; 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. Electronic address: ccchu@genetics.ac.cn.; National Key Facility for Crop Gene Resources and Genetic Improvement, Institute of Crop Sciences, Chinese Academy of Agricultural Sciences, Beijing 100081, China. Electronic address: tonghongning@caas.cn.
Plant hormone cytokinin signals through histidine-aspartic acid (H-D) phosphorelay to regulate plant growth and development. While it is well known that the phosphorelay involves histidine kinases, histidine phosphotransfer proteins (HPs), and response regulators (RRs), how this process is regulated by external components remains unknown. Here we demonstrate that protein phosphatase with kelch-like domains (PPKL1), known as a signaling component of steroid hormone brassinosteroid, is actually a cryptic inhibitor of cytokinin phosphorelay in rice (Oryza sativa). Mutation at a specific amino acid D364 of PPKL1 activates cytokinin response and thus enlarges grain size in a semi-dominant mutant named s48. Overexpression of PPKL1 containing D364, either with the deletion of the phosphatase domain or not, rescues the s48 mutant phenotype. PPKL1 interacts with OsAHP2, one of authentic HPs, and D364 resides in a region resembling the receiver domain of RRs. Accordingly, PPKL1 can utilize D364 to suppress OsAHP2-to-RR phosphorelay, whereas mutation of D364 abolishes the effect. This function of PPKL1 is independent of the phosphatase domain that is required for brassinosteroid signaling. Importantly, editing of the D364-residential region produces a diversity of semi-dominant mutations associated with variously increased grain sizes. Further screening of the edited plants enables the identification of two genotypes that confer significantly improved grain yield. Collectively, our study uncovers a noncanonical cytokinin signaling suppressor and provides a robust tool for seed rational design.
PMID: 34562665
Curr Biol , IF:10.834 , 2022 Feb , V32 (3) : P518-531.e6 doi: 10.1016/j.cub.2021.12.043
ROPGAP-dependent interaction between brassinosteroid and ROP2-GTPase signaling controls pavement cell shape in Arabidopsis.
Department of Plant Biotechnology and Bioinformatics, Ghent University, 9052 Ghent, Belgium; Center for Plant Systems Biology, VIB, 9052 Ghent, Belgium.; Developmental Genetics, Centre for Plant Molecular Biology (ZMBP), University of Tubingen, 72076 Tubingen, Germany.; FAFU-UCR Joint Centre for Horticultural Biology and Metabolomics, Haixia Institute of Science and Technology, Fujian Agriculture and Forestry University, Fuzhou 350002, P.R. China.; Developmental Genetics, Centre for Plant Molecular Biology (ZMBP), University of Tubingen, 72076 Tubingen, Germany; Department of Biology, Friedrich-Alexander University Erlangen-Nuremberg, 91054 Erlangen, Germany.; Department of Plant Biotechnology and Bioinformatics, Ghent University, 9052 Ghent, Belgium; Center for Plant Systems Biology, VIB, 9052 Ghent, Belgium. Electronic address: eurus@psb.vib-ugent.be.
The epidermal pavement cell shape in Arabidopsis is driven by chemical and mechanical cues that direct partitioning mechanisms required for the establishment of the lobe- and indentation-defining polar sites. Brassinosteroid (BR) hormones regulate pavement cell morphogenesis, but the underlying mechanism remains unclear. Here, we identified two PLECKSTRIN HOMOLOGY GTPase-ACTIVATING proteins (PHGAPs) as substrates of the GSK3-like kinase BR-INSENSITIVE2 (BIN2). The phgap1phgap2 mutant displayed severe epidermal cell shape phenotypes, and the PHGAPs were markedly enriched in the anticlinal face of the pavement cell indenting regions. BIN2 phosphorylation of PHGAPs was required for their stability and polarization. BIN2 inhibition activated ROP2-GTPase signaling specifically in the lobes because of PHGAP degradation, while the PHGAPs restrained ROP2 activity in the indentations. Hence, we connect BR and ROP2-GTPase signaling pathways via the regulation of PHGAPs and put forward the importance of spatiotemporal control of BR signaling for pavement cell interdigitation.
PMID: 35085499
Curr Biol , IF:10.834 , 2022 Feb , V32 (3) : P671-676.e5 doi: 10.1016/j.cub.2021.11.046
Female self-incompatibility type in heterostylous Primula is determined by the brassinosteroid-inactivating cytochrome P450 CYP734A50.
University of Potsdam, Institute for Biochemistry and Biology, Karl-Liebknecht-Str. 24-25, 14476 Potsdam-Golm, Germany.; Julius Kuhn-Institut (JKI) - Federal Research Centre for Cultivated Plants, Institute for Breeding Research on Horticultural Crops, Erwin-Baur-Str. 27, 06484 Quedlinburg, Germany.; Leibniz Institute of Plant Genetics and Crop Plant Research, OT Gatersleben, Corrensstrasse 3, 06466 Stadt Seeland, Germany.; University of Potsdam, Institute for Biochemistry and Biology, Karl-Liebknecht-Str. 24-25, 14476 Potsdam-Golm, Germany. Electronic address: michael.lenhard@uni-potsdam.de.
Most flowering plants are hermaphrodites, with flowers having both male and female reproductive organs. One widespread adaptation to limit self-fertilization is self-incompatibility (SI), where self-pollen fails to fertilize ovules.(1)(,)(2) In homomorphic SI, many morphologically indistinguishable mating types are found, although in heteromorphic SI, the two or three mating types are associated with different floral morphologies.(3-6) In heterostylous Primula, a hemizygous supergene determines a short-styled S-morph and a long-styled L-morph, corresponding to two different mating types, and full seed set only results from intermorph crosses.(7-9) Style length is controlled by the brassinosteroid (BR)-inactivating cytochrome P450 CYP734A50,(10) yet it remains unclear what defines the male and female incompatibility types. Here, we show that CYP734A50 also determines the female incompatibility type. Inactivating CYP734A50 converts short S-morph styles into long styles with the same incompatibility behavior as L-morph styles, and this effect can be mimicked by exogenous BR treatment. In vitro responses of S- and L-morph pollen grains and pollen tubes to increasing BR levels could only partly explain their different in vivo behavior, suggesting both direct and indirect effects of the different BR levels in S- versus L-morph stigmas and styles in controlling pollen performance. This BR-mediated SI provides a novel mechanism for preventing self-fertilization. The joint control of morphology and SI by CYP734A50 has important implications for the evolutionary buildup of the heterostylous syndrome and provides a straightforward explanation for why essentially all of the derived self-compatible homostylous Primula species are long homostyles.(11).
PMID: 34906354
J Hazard Mater , IF:10.588 , 2022 Feb , V424 (Pt C) : P127518 doi: 10.1016/j.jhazmat.2021.127518
Brassinosteroids and metalloids: Regulation of plant biology.
State Key Laboratory of Subtropical Silviculture, Zhejiang A&F University, Hangzhou 311300, China. Electronic address: anketsharma@gmail.com.; Co-Innovation Center for Sustainable Forestry in Southern China, Nanjing Forestry University, Nanjing 210037, Jiangsu, China; Bamboo Research Institute, Nanjing Forestry University, Nanjing 210037, Jiangsu, China.; Plant Stress Physiology Lab, Department of Botanical and Environment Sciences, Guru Nanak Dev University, Amritsar, Punjab 143005, India.; Department of Agriculture, Food and Environment, University of Pisa, Via del Borghetto 80, I-56124, Pisa, Italy; CIRSEC, Centre for Climatic Change Impact, University of Pisa, Via del Borghetto 80, I-56124, Pisa, Italy.; Department of Horticulture, Kulbhaskar Ashram Post Graduate College, Prayagraj, Uttar Pradesh, India.; State Key Laboratory of Subtropical Silviculture, Zhejiang A&F University, Hangzhou 311300, China. Electronic address: bszheng@zafu.edu.cn.
Metalloid contamination in the environment is one of the serious concerns posing threat to our ecosystems. Excess of metalloid concentrations (including antimony, arsenic, boron, selenium etc.) in soil results in their over accumulation in plant tissues, which ultimately causes phytotoxicity and their bio-magnification. So, it is very important to find some ecofriendly approaches to counter negative impacts of above mentioned metalloids on plant system. Brassinosteroids (BRs) belong to family of plant steroidal hormones, and are considered as one of the ecofriendly way to counter metalloid phytotoxicity. This phytohormone regulates the plant biology in presence of metalloids by modulating various key biological processes like cell signaling, primary and secondary metabolism, bio-molecule crosstalk and redox homeostasis. The present review explains the in-depth mechanisms of BR regulated plant responses in presence of metalloids, and provides some biotechnological aspects towards ecofriendly management of metalloid contamination.
PMID: 34836689
New Phytol , IF:10.151 , 2022 Feb , V233 (3) : P1238-1256 doi: 10.1111/nph.17859
GLUTAMATE RECEPTOR-like gene OsGLR3.4 is required for plant growth and systemic wound signaling in rice (Oryza sativa).
Key Laboratory of Biorheological Science and Technology of Ministry of Education, Bioengineering College of Chongqing University, 174 Shazheng Street, Chongqing, China.
Recent studies have revealed the physiological roles of glutamate receptor-like channels (GLRs) in Arabidopsis; however, the functions of GLRs in rice remain largely unknown. Here, we show that knockout of OsGLR3.4 in rice leads to brassinosteroid (BR)-regulated growth defects and reduced BR sensitivity. Electrophoretic mobility shift assays and transient transactivation assays indicated that OsGLR3.4 is the downstream target of OsBZR1. Further, agonist profile assays showed that multiple amino acids can trigger transient Ca(2+) influx in an OsGLR3.4-dependent manner, indicating that OsGLR3.4 is a Ca(2+) -permeable channel. Meanwhile, the study of internode cells demonstrated that OsGLR3.4-mediated Ca(2+) flux is required for actin filament organization and vesicle trafficking. Following root injury, the triggering of both slow wave potentials (SWPs) in leaves and the jasmonic acid (JA) response are impaired in osglr3.4 mutants, indicating that OsGLR3.4 is required for root-to-shoot systemic wound signaling in rice. Brassinosteroid treatment enhanced SWPs and OsJAZ8 expression in root-wounded plants, suggesting that BR signaling synergistically regulates the OsGLR3.4-mediated systemic wound response. In summary, this article describes a mechanism of OsGLR3.4-mediated cell elongation and long-distance systemic wound signaling in plants and provides new insights into the contribution of GLRs to plant growth and responses to mechanical wounding.
PMID: 34767648
EMBO Rep , IF:8.807 , 2022 Feb : Pe53354 doi: 10.15252/embr.202153354
Deubiquitinating enzymes UBP12 and UBP13 stabilize the brassinosteroid receptor BRI1.
Graduate School of Life Science, Hokkaido University, Sapporo, Japan.; Faculty of Science, Hokkaido University, Sapporo, Japan.; Department of Plant Biotechnology and Bioinformatics, Ghent University, Ghent, Belgium.; Center for Plant Systems Biology, VIB, Ghent, Belgium.; Department of Plant Pathology & Microbiology, Texas A&M University, College Station, TX, USA.; Department of Biochemistry & Biophysics, Texas A&M University, College Station, TX, USA.
Protein ubiquitination is a dynamic and reversible post-translational modification that controls diverse cellular processes in eukaryotes. Ubiquitin-dependent internalization, recycling, and degradation are important mechanisms that regulate the activity and the abundance of plasma membrane (PM)-localized proteins. In plants, although several ubiquitin ligases are implicated in these processes, no deubiquitinating enzymes (DUBs), have been identified that directly remove ubiquitin from membrane proteins and limit their vacuolar degradation. Here, we discover two DUB proteins, UBP12 and UBP13, that directly target the PM-localized brassinosteroid (BR) receptor BR INSENSITIVE1 (BRI1) in Arabidopsis. BRI1 protein abundance is decreased in the ubp12i/ubp13 double mutant that displayed severe growth defects and reduced sensitivity to BRs. UBP13 directly interacts with and effectively removes K63-linked polyubiquitin chains from BRI1, thereby negatively modulating its vacuolar targeting and degradation. Our study reveals that UBP12 and UBP13 play crucial roles in governing BRI1 abundance and BR signaling activity to regulate plant growth.
PMID: 35166439
Plant Physiol , IF:8.34 , 2022 Feb doi: 10.1093/plphys/kiac088
The bHLH/HLH transcription factors GhFP2 and GhACE1 antagonistically regulate fiber elongation in cotton.
Hubei Key Laboratory of Genetic Regulation and Integrative Biology, School of Life Sciences, Central China Normal University, Wuhan 430079, China.
bHLH/HLH transcription factors play important roles in cell elongation in plants. However, little is known about how bHLH/HLH transcription factors antagonistically regulate fiber elongation in cotton (Gossypium hirsutum). In this study, we report that two bHLH/HLH transcription factors, Fiber-Related Protein 2 (GhFP2) and ACTIVATOR FOR CELL ELONGATION 1 (GhACE1), function in fiber development of cotton. GhFP2 is an atypical bHLH protein without the basic region, and its expression is regulated by brassinosteroid (BR)-related BRASSINAZOLE RESISTANT 1 (GhBZR1). Overexpression of GhFP2 in cotton hindered fiber elongation, resulting in shortened fiber length. In contrast, suppression of GhFP2 expression in cotton promoted fiber development, leading to longer fibers compared with the wild type. GhFP2 neither contains a DNA binding domain nor has transcriptional activation activity. Furthermore, we identified GhACE1, a bHLH protein that interacts with GhFP2 and positively regulates fiber elongation. GhACE1 could bind to promoters of plasma membrane intrinsic protein 2;7 (GhPIP2;7) and expansions 8 (GhEXP8) for directly activating their expression, but the interaction between GhFP2 and GhACE1 suppressed transcriptional activation of these target genes by GhACE1. Taken together, our results indicate that GhACE1 promotes fiber elongation by activating expressions of GhPIP2;7 and GhEXP8, but its transcription activation on downstream genes may be obstructed by BR-modulated GhFP2. Thus, our data reveal a key mechanism for fiber cell elongation through a pair of antagonizing HLH/bHLH transcription factors in cotton.
PMID: 35226094
Plant Physiol , IF:8.34 , 2022 Feb doi: 10.1093/plphys/kiac080
Branching out underground: brassinosteroid signaling promotes lateral root development in rice.
Howard Hughes Medical Institute, Cold Spring Harbor Laboratory, Cold Spring Harbor, NY USA.
PMID: 35212723
Plant Physiol , IF:8.34 , 2022 Feb doi: 10.1093/plphys/kiac008
Brassinosteroid-regulated bHLH transcription factor CESTA induces the gibberellin 2-oxidase GA2ox7.
Biotechnology of Horticultural Crops, TUM School of Life Sciences, Technical University of Munich, Freising, Germany.; Sainsbury Laboratory, Cambridge University, Cambridge, UK.; Institute of Plant Biology, Technical University of Braunschweig, Braunschweig, Germany.
Brassinosteroids (BRs) are plant steroids that have growth-promoting capacities, which are partly enabled by an ability to induce biosynthesis of gibberellins (GAs), a second class of plant hormones. In addition, BRs can also activate GA catabolism; here we show that in Arabidopsis (Arabidopsis thaliana) the bHLH transcription factor CESTA (CES) and its homologues BRASSINOSTEROID ENHANCED EXPRESSION (BEE) 1 and 3 contribute to this activity. CES and the BEEs are BR-regulated at the transcriptional and posttranslational level and participate in different physiological processes, including vegetative and reproduction development, shade avoidance, and cold stress responses. We show that CES/BEEs can induce the expression of the class III GA 2-oxidase GA2ox7 and that this activity is increased by BRs. In BR signaling- and CES/BEE-deficient mutants, GA2ox7 expression decreased, yielding reduced levels of GA110, a product of GA2ox7 activity. In plants that over-express CES, GA2ox7 expression is hyper-responsive to BR, GA110 levels are elevated and amounts of bioactive GA are reduced. We provide evidence that CES directly binds to the GA2ox7 promoter and is activated by BRs, but can also act by BRASSINOSTEROID INSENSITIVE 1 (BRI1)-independent means. Based on these results, we propose a model for CES activity in GA catabolism where CES can be recruited for GA2ox7 induction not only by BR, but also by other factors.
PMID: 35148416
Plant Physiol , IF:8.34 , 2022 Feb doi: 10.1093/plphys/kiac043
Brassinosteroids regulate rice seed germination through the BZR1-RAmy3D transcriptional module.
Jiangsu Key Laboratory of Crop Genomics and Molecular Breeding/Jiangsu Key Laboratory of Crop Genetics and Physiology/Sate Key Laboratory of Hybrid Rice, College of Agriculture, Yangzhou University, Yangzhou 225009, Jiangsu, China.; Co-Innovation Center for Modern Production Technology of Grain Crops of Jiangsu Province/Key Laboratory of Plant Functional Genomics of the Ministry of Education, Yangzhou University, Yangzhou 225009, Jiangsu, China.
Seed dormancy and germination, two physiological processes unique to seed-bearing plants, are critical for plant growth and crop production. The phytohormone brassinosteroid (BR) regulates many aspects of plant growth and development, including seed germination. The molecular mechanisms underlying BR control of rice (Oryza sativa) seed germination are mostly unknown. We investigated the molecular regulatory cascade of BR in promoting rice seed germination and post-germination growth. Physiological assays indicated that blocking BR signaling, including introducing defects into the BR insensitive 1 (BRI1) receptor or overexpressing the glycogen synthase kinase 2 (GSK2) kinase, delayed seed germination and suppressed embryo growth. Our results also indicated that brassinazole-resistant 1 (BZR1) is the key downstream transcription factor that mediates BR regulation of seed germination by binding to the alpha-Amylase 3D (RAmy3D) promoter, which affects alpha-amylase expression and activity and the degradation of starch in the endosperm. The BZR1-RAmy3D module functions independently from the established Gibberellin MYB (GAMYB)-alpha-amylase 1A (RAmy1A) module of the gibberellin (GA) pathway. We demonstrate that the BZR1-RAmy3D module also functions in embryo-related tissues. Moreover, RNA-sequencing (RNA-seq) analysis identified more potential BZR1-responsive genes, including those involved in starch and sucrose metabolism. Our study successfully identified the role of the BZR1-RAmy3D transcriptional module in regulating rice seed germination.
PMID: 35139229
Plant Physiol , IF:8.34 , 2022 Feb doi: 10.1093/plphys/kiac046
The CCCH Zinc Finger Protein C3H15 Negatively Regulates Cell Elongation by Inhibiting Brassinosteroid Signaling.
College of Resources and Environment, Qingdao Agricultural University, Qingdao, 266109, China.; Qingdao Institute of BioEnergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao 266101, China.; Academy of Dongying Efficient Agricultural Technology and Industry on Saline and Alkaline Land in Collaboration with Qingdao Agricultural University, Dongying 257000, China.; State Key Laboratory of Wheat and Maize Crop Science and College of Agronomy, Henan Agricultural University, Zhengzhou 450002, China.; College of Agronomy, Qingdao Agricultural University, Qingdao 266109, China.; Key Laboratory of Biology and Genetic Improvement of Oil Crops, Ministry of Agriculture and Rural Affairs, Oil Crops Research Institute of the Chinese Academy of Agricultural Sciences, Wuhan 430062, China.; Key Laboratory of Plant Cell Engineering and Germplasm Innovation, Ministry of Education, School of Life Sciences, Shandong University, Jinan 250100, China.; College of Grassland Science, Qingdao Agricultural University, Qingdao 266109, China.
Plant CCCH proteins participate in the control of multiple developmental and adaptive processes, but the regulatory mechanisms underlying these processes are not well known. In this study, we showed that the Arabidopsis (Arabidopsis thaliana) CCCH protein C3H15 negatively regulates cell elongation by inhibiting brassinosteroid (BR) signaling. Genetic and biochemical evidence showed that C3H15 functions downstream of the receptor BR INSENSITIVE 1 (BRI1) as a negative regulator in the BR pathway. C3H15 is phosphorylated by the GLYCOGEN SYNTHASE KINASE 3 (GSK3)-like kinase BR-INSENSITIVE 2 (BIN2) at Ser111 in the cytoplasm in the absence of BRs. Upon BR perception, C3H15 transcription is enhanced, and the phosphorylation of C3H15 by BIN2 is reduced. The dephosphorylated C3H15 protein accumulates in the nucleus, where C3H15 regulates transcription via G-rich elements (typically GGGAGA). C3H15 and BRASSINAZOLE RESISTANT 1 (BZR1)/BRI1-EMS-SUPPRESSOR 1 (BES1), two central transcriptional regulators of BR signaling, directly suppress each other and share a number of BR-responsive target genes. Moreover, C3H15 antagonizes BZR1 and BES1 to regulate the expression of their shared cell elongation-associated target gene, SMALL AUXIN-UP RNA 15 (SAUR15). This study demonstrates that C3H15-mediated BR signaling may be parallel to, or even attenuate, the dominant BZR1 and BES1 signaling pathways to control cell elongation. This finding expands our understanding of the regulatory mechanisms underlying BR-induced cell elongation in plants.
PMID: 35139225
Int J Mol Sci , IF:5.923 , 2022 Feb , V23 (3) doi: 10.3390/ijms23031817
Heat Stress Resistance Mechanisms of Two Cucumber Varieties from Different Regions.
Key Laboratory of Horticultural Crop Biology and Germplasm Innovation in South China, Ministry of Agriculture, College of Horticulture, South China Agricultural University, Guangzhou 510642, China.; Guangdong Vegetable Engineering and Technology Research Center, South China Agricultural University, Guangzhou 510642, China.
High temperatures affect the yield and quality of vegetable crops. Unlike thermosensitive plants, thermotolerant plants have excellent systems for withstanding heat stress. This study evaluated various heat resistance indexes of the thermotolerant cucumber (TT) and thermosensitive cucumber (TS) plants at the seedling stage. The similarities and differences between the regulatory genes were assessed through transcriptome analysis to understand the mechanisms for heat stress resistance in cucumber. The TT plants exhibited enhanced leaf status, photosystem, root viability, and ROS scavenging under high temperature compared to the TS plants. Additionally, transcriptome analysis showed that the genes involved in photosynthesis, the chlorophyll metabolism, and defense responses were upregulated in TT plants but downregulated in TS plants. Zeatin riboside (ZR), brassinosteroid (BR), and jasmonic acid (JA) levels were higher in TT plants than in TS. The heat stress increased gibberellic acid (GA) and indoleacetic acid (IAA) levels in both plant lines; however, the level of GA was higher in TT. Correlation and interaction analyses revealed that heat cucumber heat resistance is regulated by a few transcription factor family genes and metabolic pathways. Our study revealed different phenotypic and physiological mechanisms of the heat response by the thermotolerant and thermosensitive cucumber plants. The plants were also shown to exhibit different expression profiles and metabolic pathways. The heat resistant pathways and genes of two cucumber varieties were also identified. These results enhance our understanding of the molecular mechanisms of cucumber response to high-temperature stress.
PMID: 35163740
Planta , IF:4.116 , 2022 Feb , V255 (4) : P73 doi: 10.1007/s00425-022-03861-y
The role of N-myristoylation in homeostasis of brassinosteroid signaling kinase 1.
School of Life Sciences, Tsinghua University, Beijing, 10084, China.; School of Life Sciences, Tsinghua University, Beijing, 10084, China. shanxy80@tsinghua.edu.cn.
MAIN CONCLUSION: The N-myristoylation is required for BSK1 proper plasma membrane targeting and protein turnover. Brassinosteroid (BR) signaling kinase 1 (BSK1), with a myristoylation site at its N-terminus to anchor at plasma membrane (PM), is involved in BR-regulated plant growth and flg22-triggered immunity responses. However, little is known about the role of N-myristoylation in BSK1 protein homeostasis. Here, we revealed that N-myristoylation is critical to the PM targeting and protein stability of BSK1. The N-myristoylation-deficient mutant BSK1(G2A) mainly distributed in the cytoplasm and retained in the endoplasmic reticulum. We further found that the BSK1(G2A) proteins were unstable and degraded through ATG8e-labled autophagic pathway. This study provides a new insight into the regulation of plant protein homeostasis.
PMID: 35220507
Phytopathology , IF:4.025 , 2022 Feb , V112 (2) : P219-231 doi: 10.1094/PHYTO-04-21-0159-R
Endophytic Bacillus subtilis TR21 Improves Banana Plant Resistance to Fusarium oxysporum f. sp. cubense and Promotes Root Growth by Upregulating the Jasmonate and Brassinosteroid Biosynthesis Pathways.
Innovative Institute for Plant Health, Zhongkai University of Agriculture and Engineering, Guangzhou 510225, People's Republic of China.; College of Agriculture and Biology, Zhongkai University of Agriculture and Engineering, Guangzhou 510225, People's Republic of China.; Institute of Fruit Tree Research, Guangdong Academy of Agricultural Sciences, Guangzhou 510000, People's Republic of China.; Zhuhai Agricultural Sciences Research Center, Zhuhai 519075, People's Republic of China.; Laboratory & Equipment Management Department, Zhongkai University of Agriculture and Engineering, Guangzhou 510225, People's Republic of China.
The banana (Musa spp.) industry experiences dramatic annual losses from Fusarium wilt of banana disease, which is caused by the fungus Fusarium oxysporum f. sp. cubense (FOC). Pisang Awak banana 'Fenza No. 1' (Musa spp. cultivar Fenza No. 1), a major banana cultivar with high resistance to F. oxysporum f. sp. cubense race 4, is considered to be ideal for growth in problematic areas. However, 'Fenza No. 1' is still affected by F. oxysporum f. sp. cubense race 1 in the field. TR21 is an endophytic Bacillus subtilis strain isolated from orchids (Dendrobium sp.). Axillary spraying of banana plants with TR21 controls Fusarium wilt of banana, decreasing the growth period and increasing yields in the field. In this study, we established that TR21 increases root growth in different monocotyledonous plant species. By axillary inoculation, TR21 induced a similar transcriptomic change as that induced by F. oxysporum f. sp. cubense race 1 but also upregulated the biosynthetic pathways for the phytohormones brassinosteroid and jasmonic acid in 'Fenza No. 1' root tissues, indicating that TR21 increases Fusarium wilt of banana resistance, shortens growth period, and increases yield of banana by inducing specific transcriptional reprogramming and modulating phytohormone levels. These findings will contribute to the identification of candidate genes related to plant resistance against fungi in a nonmodel system and facilitate further study and exploitation of endophytic biocontrol agents.
PMID: 34231376
Plants (Basel) , IF:3.935 , 2022 Feb , V11 (4) doi: 10.3390/plants11040561
Electrophysiological, Morphologic, and Transcriptomic Profiling of the Ogura-CMS, DGMS and Maintainer Broccoli Lines.
Key Laboratory of Biology and Genetic Improvement of Horticultural Crops, Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Ministry of Agriculture, #12 Zhong Guan Cun Nandajie Street, Beijing 100081, China.; China Vegetable Biotechnology (Shouguang) Co., Ltd., Shouguang 262700, China.; Institute of Agricultural Resources and Environment, Jiangsu Academy of Agricultural Sciences, Nanjing 210014, China.
To better serve breeding of broccoli, the electrophysiological, morphological and transcriptomic profiling of the isogenic Ogura-CMS, DGMS and their maintainer fertile lines, were carried out by scanning electron microscopy, investigation of agronomic traits and RNA-sequencing analysis. The agronomic traits of plant height, length of the largest leaf, plant spread angle, single head weight, head width and stem diameter showed stronger performance in Ogura-CMS broccoli than in DGMS line or maintainer fertile line. However, the Ogura-CMS broccoli was poorer in the seed yield and seed germination than in the DGMS line and maintainer fertile line. Additionally, the DGMS broccoli had longer maturation and flowering periods than the Ogura-CMS and maintainer fertile lines. There were obvious differences in the honey gland, happening in the male sterility and fertile lines of broccoli. Additionally, the mechanism regulating Ogura-CMS and DGMS in broccoli was investigated using florets transcriptome analyses of the Ogura-CMS, DGMS and maintainer fertile lines. As a result, a total of 2670 differentially expressed genes (DEGs) were detected, including 1054 up- and 1616 downregulated genes in the Ogura-CMS and DGMS lines compared to the maintainer fertile line. A number of functionally known genes involved in plant hormones (auxin, salicylic acid and brassinosteroid), five Mitochondrial Oxidative Phosphorylation (OXPHOS) genes of atp8, LOC106319879, LOC106324734, LOC106314622 and LOC106298585, and three upregulated genes (Lhcb1, Lhcb3 and Lhcb5) associated with the photosynthesis-antenna protein pathway, were obviously detected to be highly associated with reproductive development including flowering time, maturity and reproductive period in the Ogura-CMS and DGMS broccoli comparing to their maintainer fertile line. Our research would provide a comprehensive foundation for understanding the differences of electrophysiological, morphological and transcriptomic profiles in the Ogura-CMS, DGMS and maintainer broccoli, and as well as being beneficial to exploring the mechanism of male sterility in Brassica crops.
PMID: 35214894
Heliyon , 2022 Feb , V8 (2) : Pe08977 doi: 10.1016/j.heliyon.2022.e08977
Foliar brassinosteroid analogue (DI-31) sprays increase drought tolerance by improving plant growth and photosynthetic efficiency in lulo plants.
Universidad Nacional de Colombia, Sede Bogota, Facultad de Ciencias Agrarias, Departamento de Agronomia, Carrera 30 No. 45-03, Bogota, 111321, Colombia.
The use of agronomic alternatives such as plant hormone sprays has been considered a tool to mitigate drought stress. This research aimed to evaluate the use of foliar brassinosteroid analogue DI-31 (BRs) sprays on plant growth, leaf exchange and chlorophyll a fluorescence parameters, and biochemical variables in lulo (Solanum quitoense L. cv. septentrionale) seedlings grown under drought stress conditions. Seedlings were grown in plastic pots (3 L) using a mix between peat and sand (1:1 v/v) as substrate. Lulo plants were subjected to drought stress by suppressing 100% of the water needs at 30-37 and 73-80 days after transplanting (DAT). Foliar BRs analogue (DI-31) sprays were carried out at four different rates (0, 1, 2, 4, or 8 mL of analogue per liter) at different times (30, 33, 44, 60, 73, and 76 DAT). Drought stress caused a reduction in the Fv/Fm ratio, leaf gas exchange properties, total biomass, and relative water content. Foliar DI-31 sprays enhanced leaf photosynthesis in well-watered (WW) ( approximately 10.7 mumol m(-2) s(-1)) or water-stressed plants (WS) ( approximately 6.1 mumol m(-2) s(-1)) when lulo plants were treated at a dose of 4 and 8 mL.L(-1) compared to their respective controls (0 mL.L(-1) for WW: 8.83 mumol m(-2) s(-1) and WS: 2.01 mumol m(-2) s(-1)). Also, DI-31 sprays enhanced the photochemical efficiency of PSII, and plant growth. They also increased the concentration of photosynthetic pigments (TChl and Cx + c) and reduced lipid peroxidation of membranes (MDA) under drought conditions. The results allow us to suggest that the use of DI-31 at a dose of 4 or 8 mL.L(-1) can be a tool for managing water stress conditions caused by low water availability in the soil in lulo-producing areas to face situations of moderate water deficit at different times of the year.
PMID: 35243095