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Zhu J, Liu X, Huang W, An R, Xu X, Li P. 2,4-epibrassinolide delays leaf senescence in pak choi (Brassica rapa subsp. chinensis) by regulating its chlorophyll metabolic pathway and endogenous hormones content. Gene 2023:147531. [PMID: 37286019 DOI: 10.1016/j.gene.2023.147531] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2023] [Revised: 05/23/2023] [Accepted: 05/31/2023] [Indexed: 06/09/2023]
Affiliation(s)
- Junzhen Zhu
- School of Food and Biological Engineering, Jiangsu University, Zhenjiang, 212013, Jiangsu, PR China
| | - Xuesong Liu
- Institute of Agricultural Facilities and Equipment, Jiangsu Academy of Agricultural Sciences, Nanjing 210014, Jiangsu, PR China; Key Laboratory of Cold Chain Logistics Technology for Agro-Products, Ministry of Agriculture and Rural Affairs, P.R. China
| | - Wen Huang
- Nanjing Institute of Vegetable Science, Nanjing 210042, Jiangsu, PR China
| | - Ronghui An
- Jinan Fruit Research Institute, All China Federation of Supply and Marketing Cooperatives
| | - Xiaoyang Xu
- School of Food and Biological Engineering, Jiangsu University, Zhenjiang, 212013, Jiangsu, PR China
| | - Pengxia Li
- School of Food and Biological Engineering, Jiangsu University, Zhenjiang, 212013, Jiangsu, PR China; Institute of Agricultural Facilities and Equipment, Jiangsu Academy of Agricultural Sciences, Nanjing 210014, Jiangsu, PR China; Jiangsu Key Laboratory for Horticultural Crop Genetic Improvement, Nanjing 210014, Jiangsu, PR China; Key Laboratory of Cold Chain Logistics Technology for Agro-Products, Ministry of Agriculture and Rural Affairs, P.R. China.
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2
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Kruse LH, Fehr B, Chobirko JD, Moghe GD. Phylogenomic analyses across land plants reveals motifs and coexpression patterns useful for functional prediction in the BAHD acyltransferase family. FRONTIERS IN PLANT SCIENCE 2023; 14:1067613. [PMID: 36844084 PMCID: PMC9950517 DOI: 10.3389/fpls.2023.1067613] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/12/2022] [Accepted: 01/12/2023] [Indexed: 06/18/2023]
Abstract
The BAHD acyltransferase family is one of the largest enzyme families in flowering plants, containing dozens to hundreds of genes in individual genomes. Highly prevalent in angiosperm genomes, members of this family contribute to several pathways in primary and specialized metabolism. In this study, we performed a phylogenomic analysis of the family using 52 genomes across the plant kingdom to gain deeper insights into its functional evolution and enable function prediction. We found that BAHD expansion in land plants was associated with significant changes in various gene features. Using pre-defined BAHD clades, we identified clade expansions in different plant groups. In some groups, these expansions coincided with the prominence of metabolite classes such as anthocyanins (flowering plants) and hydroxycinnamic acid amides (monocots). Clade-wise motif-enrichment analysis revealed that some clades have novel motifs fixed on either the acceptor or the donor side, potentially reflecting historical routes of functional evolution. Co-expression analysis in rice and Arabidopsis further identified BAHDs with similar expression patterns, however, most co-expressed BAHDs belonged to different clades. Comparing BAHD paralogs, we found that gene expression diverges rapidly after duplication, suggesting that sub/neo-functionalization of duplicate genes occurs quickly via expression diversification. Analyzing co-expression patterns in Arabidopsis in conjunction with orthology-based substrate class predictions and metabolic pathway models led to the recovery of metabolic processes of most of the already-characterized BAHDs as well as definition of novel functional predictions for some uncharacterized BAHDs. Overall, this study provides new insights into the evolution of BAHD acyltransferases and sets up a foundation for their functional characterization.
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Affiliation(s)
- Lars H. Kruse
- Plant Biology Section, School of Integrative Plant Science, Cornell University, Ithaca, NY, United States
- Michael Smith Laboratories, University of British Columbia, Vancouver, BC, Canada
| | - Benjamin Fehr
- Computational Biology Department, Cornell University, Ithaca, NY, United States
| | - Jason D. Chobirko
- Molecular Biology and Genetics Department, Cornell University, Ithaca, NY, United States
| | - Gaurav D. Moghe
- Plant Biology Section, School of Integrative Plant Science, Cornell University, Ithaca, NY, United States
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3
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Mottiar Y, Smith RA, Karlen SD, Ralph J, Mansfield SD. Evolution of p-coumaroylated lignin in eudicots provides new tools for cell wall engineering. THE NEW PHYTOLOGIST 2023; 237:251-264. [PMID: 36196006 PMCID: PMC10099755 DOI: 10.1111/nph.18518] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/30/2022] [Accepted: 09/21/2022] [Indexed: 06/16/2023]
Abstract
Ester-linked p-coumarate (pCA) is a hallmark feature of the secondary cell walls in commelinid monocot plants. It has been shown that pCA groups arise during lignin polymerisation from the participation of monolignol conjugates assembled by p-coumaroyl-CoA:monolignol transferase (PMT) enzymes, members of the BAHD superfamily of acyltransferases. Herein, we report that a eudicot species, kenaf (Hibiscus cannabinus), naturally contains p-coumaroylated lignin in the core tissues of the stems but not in the bast fibres. Moreover, we identified a novel acyltransferase, HcPMT, that shares <30% amino acid identity with known monocot PMT sequences. Recombinant HcPMT showed a preference in enzyme assays for p-coumaroyl-CoA and benzoyl-CoA as acyl donor substrates and sinapyl alcohol as an acyl acceptor. Heterologous expression of HcPMT in hybrid poplar trees led to the incorporation of pCA in lignin, but no improvement in the saccharification potential of the wood. This work illustrates the value in mining diverse plant taxa for new monolignol acyltransferases. Furthermore, the occurrence of pCA outside monocot lineages may represent another example of convergent evolution in lignin structure. This discovery expands textbook views on cell wall biochemistry and provides a new molecular tool for engineering the lignin of biomass feedstock plants.
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Affiliation(s)
- Yaseen Mottiar
- Department of Wood ScienceUniversity of British Columbia2424 Main MallVancouverBCV6T 1Z4Canada
- Department of Energy Great Lakes Bioenergy Research CenterUniversity of Wisconsin1552 University AvenueMadisonWI53726USA
| | - Rebecca A. Smith
- Department of Energy Great Lakes Bioenergy Research CenterUniversity of Wisconsin1552 University AvenueMadisonWI53726USA
- Department of BiochemistryUniversity of Wisconsin433 Babcock DriveMadisonWI53706USA
| | - Steven D. Karlen
- Department of Energy Great Lakes Bioenergy Research CenterUniversity of Wisconsin1552 University AvenueMadisonWI53726USA
- Department of BiochemistryUniversity of Wisconsin433 Babcock DriveMadisonWI53706USA
| | - John Ralph
- Department of Energy Great Lakes Bioenergy Research CenterUniversity of Wisconsin1552 University AvenueMadisonWI53726USA
- Department of BiochemistryUniversity of Wisconsin433 Babcock DriveMadisonWI53706USA
| | - Shawn D. Mansfield
- Department of Wood ScienceUniversity of British Columbia2424 Main MallVancouverBCV6T 1Z4Canada
- Department of Energy Great Lakes Bioenergy Research CenterUniversity of Wisconsin1552 University AvenueMadisonWI53726USA
- Department of BotanyUniversity of British Columbia6270 University BoulevardVancouverBCV6T 1Z4Canada
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4
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Huang P, Li Z, Guo H. New Advances in the Regulation of Leaf Senescence by Classical and Peptide Hormones. FRONTIERS IN PLANT SCIENCE 2022; 13:923136. [PMID: 35837465 PMCID: PMC9274171 DOI: 10.3389/fpls.2022.923136] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/19/2022] [Accepted: 06/02/2022] [Indexed: 06/15/2023]
Abstract
Leaf senescence is the last stage of leaf development, manifested by leaf yellowing due to the loss of chlorophyll, along with the degradation of macromolecules and facilitates nutrient translocation from the sink to the source tissues, which is essential for the plants' fitness. Leaf senescence is controlled by a sophisticated genetic network that has been revealed through the study of the molecular mechanisms of hundreds of senescence-associated genes (SAGs), which are involved in multiple layers of regulation. Leaf senescence is primarily regulated by plant age, but also influenced by a variety of factors, including phytohormones and environmental stimuli. Phytohormones, as important signaling molecules in plant, contribute to the onset and progression of leaf senescence. Recently, peptide hormones have been reported to be involved in the regulation of leaf senescence, enriching the significance of signaling molecules in controlling leaf senescence. This review summarizes recent advances in the regulation of leaf senescence by classical and peptide hormones, aiming to better understand the coordinated network of different pathways during leaf senescence.
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Affiliation(s)
- Peixin Huang
- Beijing Advanced Innovation Center for Tree Breeding by Molecular Design, National Engineering Research Center for Tree Breeding and Ecological Restoration, College of Biological Sciences and Technology, Beijing Forestry University, Beijing, China
| | - Zhonghai Li
- Beijing Advanced Innovation Center for Tree Breeding by Molecular Design, National Engineering Research Center for Tree Breeding and Ecological Restoration, College of Biological Sciences and Technology, Beijing Forestry University, Beijing, China
| | - Hongwei Guo
- Beijing Advanced Innovation Center for Tree Breeding by Molecular Design, National Engineering Research Center for Tree Breeding and Ecological Restoration, College of Biological Sciences and Technology, Beijing Forestry University, Beijing, China
- Key Laboratory of Molecular Design for Plant Cell Factory of Guangdong Higher Education Institutes, Department of Biology, Southern University of Science and Technology, Shenzhen, China
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5
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Xu R, Guo Y, Peng S, Liu J, Li P, Jia W, Zhao J. Molecular Targets and Biological Functions of cAMP Signaling in Arabidopsis. Biomolecules 2021; 11:biom11050688. [PMID: 34063698 PMCID: PMC8147800 DOI: 10.3390/biom11050688] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2021] [Revised: 04/29/2021] [Accepted: 04/30/2021] [Indexed: 01/11/2023] Open
Abstract
Cyclic AMP (cAMP) is a pivotal signaling molecule existing in almost all living organisms. However, the mechanism of cAMP signaling in plants remains very poorly understood. Here, we employ the engineered activity of soluble adenylate cyclase to induce cellular cAMP elevation in Arabidopsis thaliana plants and identify 427 cAMP-responsive genes (CRGs) through RNA-seq analysis. Induction of cellular cAMP elevation inhibits seed germination, disturbs phytohormone contents, promotes leaf senescence, impairs ethylene response, and compromises salt stress tolerance and pathogen resistance. A set of 62 transcription factors are among the CRGs, supporting a prominent role of cAMP in transcriptional regulation. The CRGs are significantly overrepresented in the pathways of plant hormone signal transduction, MAPK signaling, and diterpenoid biosynthesis, but they are also implicated in lipid, sugar, K+, nitrate signaling, and beyond. Our results provide a basic framework of cAMP signaling for the community to explore. The regulatory roles of cAMP signaling in plant plasticity are discussed.
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Affiliation(s)
- Ruqiang Xu
- School of Agricultural Sciences, Zhengzhou University, Zhengzhou 450001, China; (Y.G.); (S.P.); (J.L.); (P.L.); (W.J.); (J.Z.)
- Zhengzhou Research Base, State Key Laboratory of Cotton Biology, Zhengzhou University, Zhengzhou 450001, China
- Correspondence: ; Tel.: +86-0371-6778-5095
| | - Yanhui Guo
- School of Agricultural Sciences, Zhengzhou University, Zhengzhou 450001, China; (Y.G.); (S.P.); (J.L.); (P.L.); (W.J.); (J.Z.)
| | - Song Peng
- School of Agricultural Sciences, Zhengzhou University, Zhengzhou 450001, China; (Y.G.); (S.P.); (J.L.); (P.L.); (W.J.); (J.Z.)
| | - Jinrui Liu
- School of Agricultural Sciences, Zhengzhou University, Zhengzhou 450001, China; (Y.G.); (S.P.); (J.L.); (P.L.); (W.J.); (J.Z.)
| | - Panyu Li
- School of Agricultural Sciences, Zhengzhou University, Zhengzhou 450001, China; (Y.G.); (S.P.); (J.L.); (P.L.); (W.J.); (J.Z.)
| | - Wenjing Jia
- School of Agricultural Sciences, Zhengzhou University, Zhengzhou 450001, China; (Y.G.); (S.P.); (J.L.); (P.L.); (W.J.); (J.Z.)
| | - Junheng Zhao
- School of Agricultural Sciences, Zhengzhou University, Zhengzhou 450001, China; (Y.G.); (S.P.); (J.L.); (P.L.); (W.J.); (J.Z.)
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6
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Bai Y, Fernández-Calvo P, Ritter A, Huang AC, Morales-Herrera S, Bicalho KU, Karady M, Pauwels L, Buyst D, Njo M, Ljung K, Martins JC, Vanneste S, Beeckman T, Osbourn A, Goossens A, Pollier J. Modulation of Arabidopsis root growth by specialized triterpenes. THE NEW PHYTOLOGIST 2021; 230:228-243. [PMID: 33616937 DOI: 10.1111/nph.17144] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/22/2020] [Accepted: 12/01/2020] [Indexed: 05/21/2023]
Abstract
Plant roots are specialized belowground organs that spatiotemporally shape their development in function of varying soil conditions. This root plasticity relies on intricate molecular networks driven by phytohormones, such as auxin and jasmonate (JA). Loss-of-function of the NOVEL INTERACTOR OF JAZ (NINJA), a core component of the JA signaling pathway, leads to enhanced triterpene biosynthesis, in particular of the thalianol gene cluster, in Arabidopsis thaliana roots. We have investigated the biological role of thalianol and its derivatives by focusing on Thalianol Synthase (THAS) and Thalianol Acyltransferase 2 (THAA2), two thalianol cluster genes that are upregulated in the roots of ninja mutant plants. THAS and THAA2 activity was investigated in yeast, and metabolite and phenotype profiling of thas and thaa2 loss-of-function plants was carried out. THAA2 was shown to be responsible for the acetylation of thalianol and its derivatives, both in yeast and in planta. In addition, THAS and THAA2 activity was shown to modulate root development. Our results indicate that the thalianol pathway is not only controlled by phytohormonal cues, but also may modulate phytohormonal action itself, thereby affecting root development and interaction with the environment.
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Affiliation(s)
- Yuechen Bai
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Technologiepark 71, Ghent, 9052, Belgium
- VIB Center for Plant Systems Biology, Technologiepark 71, Ghent, 9052, Belgium
| | - Patricia Fernández-Calvo
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Technologiepark 71, Ghent, 9052, Belgium
- VIB Center for Plant Systems Biology, Technologiepark 71, Ghent, 9052, Belgium
| | - Andrés Ritter
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Technologiepark 71, Ghent, 9052, Belgium
- VIB Center for Plant Systems Biology, Technologiepark 71, Ghent, 9052, Belgium
| | - Ancheng C Huang
- Department of Metabolic Biology, John Innes Centre, Norwich Research Park, Colney Lane, Norwich,, NR4 7UH, UK
| | - Stefania Morales-Herrera
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Technologiepark 71, Ghent, 9052, Belgium
- VIB Center for Plant Systems Biology, Technologiepark 71, Ghent, 9052, Belgium
- Laboratory of Molecular Cell Biology, KU Leuven, Kasteelpark Arenberg 31, Leuven, 3000, Belgium
- VIB Center for Microbiology, Kasteelpark Arenberg 31, Leuven, 3000, Belgium
| | - Keylla U Bicalho
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Technologiepark 71, Ghent, 9052, Belgium
- VIB Center for Plant Systems Biology, Technologiepark 71, Ghent, 9052, Belgium
- Department of Organic Chemistry, Institute of Chemistry, São Paulo State University (UNESP), Araraquara, São Paulo, 14800-060, Brazil
| | - Michal Karady
- Laboratory of Growth Regulators, Institute of Experimental Botany of the Czech Academy of Sciences and Faculty of Science of Palacký University, Šlechtitelů 27, Olomouc, CZ-78371, Czech Republic
| | - Laurens Pauwels
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Technologiepark 71, Ghent, 9052, Belgium
- VIB Center for Plant Systems Biology, Technologiepark 71, Ghent, 9052, Belgium
| | - Dieter Buyst
- Department of Organic Chemistry, Ghent University, Ghent, 9000, Belgium
| | - Maria Njo
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Technologiepark 71, Ghent, 9052, Belgium
- VIB Center for Plant Systems Biology, Technologiepark 71, Ghent, 9052, Belgium
| | - Karen Ljung
- Department of Forest Genetics and Plant Physiology, Umeå Plant Science Centre, Swedish University of Agricultural Sciences, Umeå, SE-901 83, Sweden
| | - José C Martins
- Department of Organic Chemistry, Ghent University, Ghent, 9000, Belgium
| | - Steffen Vanneste
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Technologiepark 71, Ghent, 9052, Belgium
- VIB Center for Plant Systems Biology, Technologiepark 71, Ghent, 9052, Belgium
- Lab of Plant Growth Analysis, Ghent University Global Campus, Incheon, 21985, Korea
| | - Tom Beeckman
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Technologiepark 71, Ghent, 9052, Belgium
- VIB Center for Plant Systems Biology, Technologiepark 71, Ghent, 9052, Belgium
| | - Anne Osbourn
- Department of Metabolic Biology, John Innes Centre, Norwich Research Park, Colney Lane, Norwich,, NR4 7UH, UK
| | - Alain Goossens
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Technologiepark 71, Ghent, 9052, Belgium
- VIB Center for Plant Systems Biology, Technologiepark 71, Ghent, 9052, Belgium
| | - Jacob Pollier
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Technologiepark 71, Ghent, 9052, Belgium
- VIB Center for Plant Systems Biology, Technologiepark 71, Ghent, 9052, Belgium
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7
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Li T, Kang X, Lei W, Yao X, Zou L, Zhang D, Lin H. SHY2 as a node in the regulation of root meristem development by auxin, brassinosteroids, and cytokinin. JOURNAL OF INTEGRATIVE PLANT BIOLOGY 2020; 62:1500-1517. [PMID: 32239656 DOI: 10.1111/jipb.12931] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/16/2019] [Accepted: 03/25/2020] [Indexed: 05/27/2023]
Abstract
In multicellular organisms, the balance between cell division and differentiation determines organ size, and represents a central unknown in developmental biology. In Arabidopsis roots, this balance is mediated between cytokinin and auxin through a regulatory circuit converging on the IAA3/SHORT HYPOCOTYL 2 (SHY2) gene. Here, we show that crosstalk between brassinosteroids (BRs) and auxin occurs in the vascular transition zone to promote root meristem development. We found that BR increases root meristem size by up-regulating expression of the PINFORMED 7 (PIN7) gene and down-regulating expression of the SHY2 gene. In addition, BES1 could directly bind to the promoter regions of both PIN7 and SHY2, indicating that PIN7 and SHY2 mediate the BR-induced growth of the root meristem by serving as direct targets of BES1. Moreover, the PIN7 overexpression and loss-of-function SHY2 mutant were sensitive to the effects of BR and could partially suppress the short-root phenotypes associated with deficient BR signaling. Interestingly, BRs could inhibit the accumulation of SHY2 protein in response to cytokinin. Taken together, these findings suggest that a complex equilibrium model exists in which regulatory interactions among BRs, auxin, and cytokinin regulate optimal root growth.
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Affiliation(s)
- Taotao Li
- Ministry of Education Key Laboratory for Bio-Resource and Eco-Environment, College of Life Science, State Key Laboratory of Hydraulics and Mountain River Engineering, Sichuan University, Chengdu, 610064, China
- School of Life Science and Engineering, Henan University of Urban Construction, Pingdingshan, 467044, China
| | - Xinke Kang
- Ministry of Education Key Laboratory for Bio-Resource and Eco-Environment, College of Life Science, State Key Laboratory of Hydraulics and Mountain River Engineering, Sichuan University, Chengdu, 610064, China
| | - Wei Lei
- Ministry of Education Key Laboratory for Bio-Resource and Eco-Environment, College of Life Science, State Key Laboratory of Hydraulics and Mountain River Engineering, Sichuan University, Chengdu, 610064, China
| | - Xiuhong Yao
- Ministry of Education Key Laboratory for Bio-Resource and Eco-Environment, College of Life Science, State Key Laboratory of Hydraulics and Mountain River Engineering, Sichuan University, Chengdu, 610064, China
| | - Lijuan Zou
- Ecological Security and Protection Key Laboratory of Sichuan Province, Mianyang Normal University, Mianyang, 621000, China
| | - Dawei Zhang
- Ministry of Education Key Laboratory for Bio-Resource and Eco-Environment, College of Life Science, State Key Laboratory of Hydraulics and Mountain River Engineering, Sichuan University, Chengdu, 610064, China
| | - Honghui Lin
- Ministry of Education Key Laboratory for Bio-Resource and Eco-Environment, College of Life Science, State Key Laboratory of Hydraulics and Mountain River Engineering, Sichuan University, Chengdu, 610064, China
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8
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Re-activation of Stem Cell Pathways for Pattern Restoration in Plant Wound Healing. Cell 2020; 177:957-969.e13. [PMID: 31051107 PMCID: PMC6506278 DOI: 10.1016/j.cell.2019.04.015] [Citation(s) in RCA: 69] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2018] [Revised: 11/18/2018] [Accepted: 04/07/2019] [Indexed: 11/23/2022]
Abstract
Patterning in plants relies on oriented cell divisions and acquisition of specific cell identities. Plants regularly endure wounds caused by abiotic or biotic environmental stimuli and have developed extraordinary abilities to restore their tissues after injuries. Here, we provide insight into a mechanism of restorative patterning that repairs tissues after wounding. Laser-assisted elimination of different cells in Arabidopsis root combined with live-imaging tracking during vertical growth allowed analysis of the regeneration processes in vivo. Specifically, the cells adjacent to the inner side of the injury re-activated their stem cell transcriptional programs. They accelerated their progression through cell cycle, coordinately changed the cell division orientation, and ultimately acquired de novo the correct cell fates to replace missing cells. These observations highlight existence of unknown intercellular positional signaling and demonstrate the capability of specified cells to re-acquire stem cell programs as a crucial part of the plant-specific mechanism of wound healing.
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Peng H, Neff MM. CIRCADIAN CLOCK ASSOCIATED 1 and ATAF2 differentially suppress cytochrome P450-mediated brassinosteroid inactivation. JOURNAL OF EXPERIMENTAL BOTANY 2020; 71:970-985. [PMID: 31639820 PMCID: PMC6977193 DOI: 10.1093/jxb/erz468] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/01/2018] [Accepted: 10/15/2019] [Indexed: 05/20/2023]
Abstract
Brassinosteroids (BRs) are a group of steroid hormones regulating plant growth and development. Since BRs do not undergo transport among plant tissues, their metabolism is tightly regulated by transcription factors (TFs) and feedback loops. BAS1 (CYP734A1, formerly CYP72B1) and SOB7 (CYP72C1) are two BR-inactivating cytochrome P450s identified in Arabidopsis thaliana. We previously found that a TF ATAF2 (ANAC081) suppresses BAS1 and SOB7 expression by binding to the Evening Element (EE) and CIRCADIAN CLOCK ASSOCIATED 1 (CCA1)-binding site (CBS) on their promoters. Both the EE and CBS are known binding targets of the circadian regulatory protein CCA1. Here, we confirm that CCA1 binds the EE and CBS motifs on BAS1 and SOB7 promoters, respectively. Elevated accumulations of BAS1 and SOB7 transcripts in the CCA1 null mutant cca1-1 indicate that CCA1 is a repressor of their expression. When compared with either cca1-1 or the ATAF2 null mutant ataf2-2, the cca1-1 ataf2-2 double mutant shows higher SOB7 transcript accumulations and a stronger BR-insensitive phenotype of hypocotyl elongation in white light. CCA1 interacts with ATAF2 at both DNA-protein and protein-protein levels. ATAF2, BAS1, and SOB7 are all circadian regulated with distinct expression patterns. These results demonstrate that CCA1 and ATAF2 differentially suppress BAS1- and SOB7-mediated BR inactivation.
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Affiliation(s)
- Hao Peng
- Department of Crop and Soil Sciences, Washington State University, Pullman, WA, USA
| | - Michael M Neff
- Department of Crop and Soil Sciences, Washington State University, Pullman, WA, USA
- Correspondence:
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10
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Wei Z, Li J. Regulation of Brassinosteroid Homeostasis in Higher Plants. FRONTIERS IN PLANT SCIENCE 2020; 11:583622. [PMID: 33133120 PMCID: PMC7550685 DOI: 10.3389/fpls.2020.583622] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/15/2020] [Accepted: 09/09/2020] [Indexed: 05/03/2023]
Abstract
Brassinosteroids (BRs) are known as one of the major classes of phytohormones essential for various processes during normal plant growth, development, and adaptations to biotic and abiotic stresses. Significant progress has been achieved on revealing mechanisms regulating BR biosynthesis, catabolism, and signaling in many crops and in model plant Arabidopsis. It is known that BRs control plant growth and development in a dosage-dependent manner. Maintenance of BR homeostasis is therefore critical for optimal functions of BRs. In this review, updated discoveries on mechanisms controlling BR homeostasis in higher plants in response to internal and external cues are discussed.
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11
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Rozhon W, Akter S, Fernandez A, Poppenberger B. Inhibitors of Brassinosteroid Biosynthesis and Signal Transduction. Molecules 2019; 24:E4372. [PMID: 31795392 PMCID: PMC6930552 DOI: 10.3390/molecules24234372] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2019] [Revised: 11/25/2019] [Accepted: 11/26/2019] [Indexed: 12/19/2022] Open
Abstract
Chemical inhibitors are invaluable tools for investigating protein function in reverse genetic approaches. Their application bears many advantages over mutant generation and characterization. Inhibitors can overcome functional redundancy, their application is not limited to species for which tools of molecular genetics are available and they can be applied to specific tissues or developmental stages, making them highly convenient for addressing biological questions. The use of inhibitors has helped to elucidate hormone biosynthesis and signaling pathways and here we review compounds that were developed for the plant hormones brassinosteroids (BRs). BRs are steroids that have strong growth-promoting capacities, are crucial for all stages of plant development and participate in adaptive growth processes and stress response reactions. In the last two decades, impressive progress has been made in BR inhibitor development and application, which has been instrumental for studying BR modes of activity and identifying and characterizing key players. Both, inhibitors that target biosynthesis, such as brassinazole, and inhibitors that target signaling, such as bikinin, exist and in a comprehensive overview we summarize knowledge and methodology that enabled their design and key findings of their use. In addition, the potential of BR inhibitors for commercial application in plant production is discussed.
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Affiliation(s)
- Wilfried Rozhon
- Biotechnology of Horticultural Crops, TUM School of Life Sciences Weihenstephan, Technical University of Munich, Liesel-Beckmann-Straße 1, 85354 Freising, Germany
| | | | | | - Brigitte Poppenberger
- Biotechnology of Horticultural Crops, TUM School of Life Sciences Weihenstephan, Technical University of Munich, Liesel-Beckmann-Straße 1, 85354 Freising, Germany
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12
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Ruan Y, Halat LS, Khan D, Jancowski S, Ambrose C, Belmonte MF, Wasteneys GO. The Microtubule-Associated Protein CLASP Sustains Cell Proliferation through a Brassinosteroid Signaling Negative Feedback Loop. Curr Biol 2018; 28:2718-2729.e5. [DOI: 10.1016/j.cub.2018.06.048] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2018] [Revised: 04/19/2018] [Accepted: 06/20/2018] [Indexed: 12/18/2022]
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Zhang Z, Xu L. Arabidopsis BRASSINOSTEROID INACTIVATOR2 is a typical BAHD acyltransferase involved in brassinosteroid homeostasis. JOURNAL OF EXPERIMENTAL BOTANY 2018; 69:1925-1941. [PMID: 29462426 DOI: 10.1093/jxb/ery057] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/24/2017] [Accepted: 02/03/2018] [Indexed: 06/08/2023]
Abstract
Brassinosteroids (BRs) are plant-specific steroidal hormones; BR homeostasis is crucial for various aspects of plant growth and development. However, to date, the BR inactivation process has not been thoroughly elucidated. In this study, we identified and characterized a novel BAHD family acyltransferase gene, BRASSINOSTEROID INACTIVATOR2 (BIA2), involved in BR inactivation. BIA2-overexpressing (OE-BIA2) plants displayed typical BR-deficient phenotypes, which were rescued by exogenous BR treatment. Real-time qRT-PCR and transcriptome analyses showed that expression levels of virtually all of the BR biosynthetic genes were increased, whereas the expression of many BR inactivation genes was reduced in OE-BIA2 plants. Root inhibition assays showed that the root growth of OE-BIA2 plants was inhibited. We obtained plants with an intermediate phenotype by crossing the OE-BIA2 plants with BRASSINOSTEROID-INSENSITIVE1 (BRI1)-overexpressing plants. The null BIA2 mutants had longer hypocotyls in the dark. BIA2 was predominantly expressed in roots, and its expression was induced by 24-epibrassinolide or dark treatment, but it exhibited a differential expression pattern compared with its homologue, BIA1. Furthermore, genetic transformation with point-mutant and deleted-BIA2 constructs confirmed that the HXXXD motif is essential for the function of BIA2. Taken together, these findings indicate that BIA2 is a typical BAHD acyltransferase that is involved in BR homeostasis and may inactivate bioactive BRs by esterification, particularly in roots and hypocotyls under dark conditions.
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Affiliation(s)
- Zhiqiang Zhang
- National Key Laboratory of Crop Genetic Improvement, National Center of Rapeseed Improvement, Huazhong Agricultural University, Wuhan, China
| | - Liping Xu
- National Key Laboratory of Wheat and Maize Crops Science, Collaborative Innovation Center of Henan Grain Crops, College of Agronomy, Henan Agricultural University, Zhengzhou, China
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Lv B, Tian H, Zhang F, Liu J, Lu S, Bai M, Li C, Ding Z. Brassinosteroids regulate root growth by controlling reactive oxygen species homeostasis and dual effect on ethylene synthesis in Arabidopsis. PLoS Genet 2018; 14:e1007144. [PMID: 29324765 PMCID: PMC5783399 DOI: 10.1371/journal.pgen.1007144] [Citation(s) in RCA: 101] [Impact Index Per Article: 16.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2017] [Revised: 01/24/2018] [Accepted: 12/04/2017] [Indexed: 02/07/2023] Open
Abstract
The brassinosteroids (BRs) represent a class of phytohormones, which regulate numerous aspects of growth and development. Here, a det2-9 mutant defective in BR synthesis was identified from an EMS mutant screening for defects in root length, and was used to investigate the role of BR in root development in Arabidopsis. The det2-9 mutant displays a short-root phenotype, which is result from the reduced cell number in root meristem and decreased cell size in root maturation zone. Ethylene synthesis is highly increased in the det2-9 mutant compared with the wild type, resulting in the hyper-accumulation of ethylene and the consequent inhibition of root growth. The short-root phenotype of det2-9 was partially recovered in the det2-9/acs9 double mutant and det2-9/ein3/eil1-1 triple mutant which have defects either in ethylene synthesis or ethylene signaling, respectively. Exogenous application of BR showed that BRs either positively or negatively regulate ethylene biosynthesis in a concentration-dependent manner. Different from the BR induced ethylene biosynthesis through stabilizing ACSs stability, we found that the BR signaling transcription factors BES1 and BZR1 directly interacted with the promoters of ACS7, ACS9 and ACS11 to repress their expression, indicating a native regulation mechanism under physiological levels of BR. In addition, the det2-9 mutant displayed over accumulated superoxide anions (O2-) compared with the wild-type control, and the increased O2- level was shown to contribute to the inhibition of root growth. The BR-modulated control over the accumulation of O2- acted via the peroxidase pathway rather than via the NADPH oxidase pathway. This study reveals an important mechanism by which the hormone cross-regulation between BRs and ethylene or/and ROS is involved in controlling root growth and development in Arabidopsis.
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Affiliation(s)
- Bingsheng Lv
- The Key Laboratory of Plant Cell Engineering and Germplasm Innovation, Ministry of Education, College of Life Science, Shandong University, Jinan, People’s Republic of China
| | - Huiyu Tian
- The Key Laboratory of Plant Cell Engineering and Germplasm Innovation, Ministry of Education, College of Life Science, Shandong University, Jinan, People’s Republic of China
| | - Feng Zhang
- The Key Laboratory of Plant Cell Engineering and Germplasm Innovation, Ministry of Education, College of Life Science, Shandong University, Jinan, People’s Republic of China
| | - Jiajia Liu
- The Key Laboratory of Plant Cell Engineering and Germplasm Innovation, Ministry of Education, College of Life Science, Shandong University, Jinan, People’s Republic of China
| | - Songchong Lu
- The Key Laboratory of Plant Cell Engineering and Germplasm Innovation, Ministry of Education, College of Life Science, Shandong University, Jinan, People’s Republic of China
| | - Mingyi Bai
- The Key Laboratory of Plant Cell Engineering and Germplasm Innovation, Ministry of Education, College of Life Science, Shandong University, Jinan, People’s Republic of China
| | - Chuanyou Li
- State Key Laboratory of Plant Genomics, National Centre for Plant Gene Research (Beijing), Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, People’s Republic of China
| | - Zhaojun Ding
- The Key Laboratory of Plant Cell Engineering and Germplasm Innovation, Ministry of Education, College of Life Science, Shandong University, Jinan, People’s Republic of China
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Han YJ, Kim YS, Hwang OJ, Roh J, Ganguly K, Kim SK, Hwang I, Kim JI. Overexpression of Arabidopsis thaliana brassinosteroid-related acyltransferase 1 gene induces brassinosteroid-deficient phenotypes in creeping bentgrass. PLoS One 2017; 12:e0187378. [PMID: 29084267 PMCID: PMC5662239 DOI: 10.1371/journal.pone.0187378] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2017] [Accepted: 10/18/2017] [Indexed: 11/19/2022] Open
Abstract
Brassinosteroids (BRs) are naturally occurring steroidal hormones that play diverse roles in various processes during plant growth and development. Thus, genetic manipulation of endogenous BR levels might offer a way of improving the agronomic traits of crops, including plant architecture and stress tolerance. In this study, we produced transgenic creeping bentgrass (Agrostis stolonifera L.) overexpressing a BR-inactivating enzyme, Arabidopsis thaliana BR-related acyltransferase 1 (AtBAT1), which is known to catalyze the conversion of BR intermediates to inactive acylated conjugates. After putative transgenic plants were selected using herbicide resistance assay, genomic integration of the AtBAT1 gene was confirmed by genomic PCR and Southern blot analysis, and transgene expression was validated by northern blot analysis. The transgenic creeping bentgrass plants exhibited BR-deficient phenotypes, including reduced plant height with shortened internodes (i.e., semi-dwarf), reduced leaf growth rates with short, wide, and thick architecture, high chlorophyll contents, decreased numbers of vascular bundles, and large lamina joint bending angles (i.e., erect leaves). Subsequent analyses showed that the transgenic plants had significantly reduced amounts of endogenous BR intermediates, including typhasterol, 6-deoxocastasterone, and castasterone. Moreover, the AtBAT1 transgenic plants displayed drought tolerance as well as delayed senescence. Therefore, the results of the present study demonstrate that overexpression of an Arabidopsis BR-inactivating enzyme can reduce the endogenous levels of BRs in creeping bentgrass resulting in BR-deficient phenotypes, indicating that the AtBAT1 gene from a dicot plant is also functional in the monocot crop.
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Affiliation(s)
- Yun-Jeong Han
- Department of Biotechnology and Kumho Life Science Laboratory, Chonnam National University, Gwangju, Republic of Korea
| | - Young Soon Kim
- Department of Biotechnology and Kumho Life Science Laboratory, Chonnam National University, Gwangju, Republic of Korea
| | - Ok-Jin Hwang
- Department of Biotechnology and Kumho Life Science Laboratory, Chonnam National University, Gwangju, Republic of Korea
| | - Jeehee Roh
- Department of Life Science, Chung-Ang University, Seoul, Republic of Korea
| | - Keya Ganguly
- Department of Biotechnology and Kumho Life Science Laboratory, Chonnam National University, Gwangju, Republic of Korea
| | - Seong-Ki Kim
- Department of Life Science, Chung-Ang University, Seoul, Republic of Korea
| | - Ildoo Hwang
- Department of Life Sciences and Biotechnology Research Center, Pohang University of Science and Technology, Pohang, Republic of Korea
| | - Jeong-Il Kim
- Department of Biotechnology and Kumho Life Science Laboratory, Chonnam National University, Gwangju, Republic of Korea
- * E-mail:
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16
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Haslam TM, Gerelle WK, Graham SW, Kunst L. The Unique Role of the ECERIFERUM2-LIKE Clade of the BAHD Acyltransferase Superfamily in Cuticular Wax Metabolism. PLANTS (BASEL, SWITZERLAND) 2017; 6:E23. [PMID: 28608803 PMCID: PMC5489795 DOI: 10.3390/plants6020023] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/29/2017] [Revised: 05/27/2017] [Accepted: 06/01/2017] [Indexed: 11/16/2022]
Abstract
The elongation of very-long-chain fatty acids is a conserved process used for the production of many metabolites, including plant cuticular waxes. The elongation of precursors of the most abundant cuticular wax components of some plants, however, is unique in requiring ECERIFERUM2-LIKE (CER2-LIKE) proteins. CER2-LIKEs are a clade within the BAHD superfamily of acyltransferases. They are known to be required for cuticular wax production in both Arabidopsis and maize based on mutant studies. Heterologous expression of Arabidopsis and rice CER2-LIKEs in Saccharomyces cerevisiae has demonstrated that they modify the chain-length specificity of elongation when paired with particular condensing enzymes. Despite sequence homology, CER2-LIKEs are distinct from the BAHD superfamily in that they do not appear to use acyl transfer activity to fulfill their biological function. Here, we review the discovery and characterization of CER2-LIKEs, propose several models to explain their function, and explore the importance of CER2-LIKE proteins for the evolution of plant cuticles.
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Affiliation(s)
- Tegan M Haslam
- Department of Botany, University of British Columbia, Vancouver, BC V6T 1Z4, Canada.
| | - Wesley K Gerelle
- Department of Botany, University of British Columbia, Vancouver, BC V6T 1Z4, Canada.
| | - Sean W Graham
- Department of Botany, University of British Columbia, Vancouver, BC V6T 1Z4, Canada.
| | - Ljerka Kunst
- Department of Botany, University of British Columbia, Vancouver, BC V6T 1Z4, Canada.
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Sharma A, Thakur S, Kumar V, Kanwar MK, Kesavan AK, Thukral AK, Bhardwaj R, Alam P, Ahmad P. Pre-sowing Seed Treatment with 24-Epibrassinolide Ameliorates Pesticide Stress in Brassica juncea L. through the Modulation of Stress Markers. FRONTIERS IN PLANT SCIENCE 2016; 7:1569. [PMID: 27853460 PMCID: PMC5089990 DOI: 10.3389/fpls.2016.01569] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/23/2016] [Accepted: 10/05/2016] [Indexed: 05/18/2023]
Abstract
The present experiment was designed to assess the effects of seed soaking with 24-epibrassinolide (EBR) on the physiology of Brassica juncea L. seedlings grown under imidacloprid (IMI) toxicity. Application of EBR increased the length of seedlings, dry weight, and pigment contents, polyphenols, total phenols, and organic acids under IMI toxicity. The expression of genes coding key enzymes of pigment, phenols, polyphenols, and organic acid biosynthetic pathways was also studied including CHLASE (chlorophyllase), PSY (phytoene synthase), CHS (chalcone synthase) and PAL (phenylalanine ammonialyase), CS (citrate synthase), SUCLG1 (succinyl Co-A ligase,), SDH (succinate dehydrogenase), FH (fumarate hydratase), MS (malate synthase). Multiple linear regression (MLR) analysis revealed that IMI application regressed negatively on seedling length, dry weight and total chlorophyll content. However, EBR seed treatment regressed positively on all the parameters studied. Moreover, interaction between IMI and EBR showed positive regression for growth parameters, content of pigments, total polyphenol, total phenol and malate, and expression of PSY and PAL. Negative interactions were noticed for the contents of fumarate, succinate and citrate, and expression of CHS and all genes studied related to organic acid metabolism. In conclusion, EBR enhanced the growth and contents of all studied metabolites by regulating the gene expression of B. juncea seedlings under IMI stress.
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Affiliation(s)
- Anket Sharma
- Plant Stress Physiology Lab, Department of Botanical and Environmental Sciences, Guru Nanak Dev UniversityAmritsar, India
| | - Sharad Thakur
- Department of Molecular Biology and Biochemistry, Guru Nanak Dev UniversityAmritsar, India
| | - Vinod Kumar
- Plant Stress Physiology Lab, Department of Botanical and Environmental Sciences, Guru Nanak Dev UniversityAmritsar, India
| | - Mukesh K. Kanwar
- Department of Botany and Environmental Science, Sri Guru Granth Sahib World UniversityFatehgarh Sahib, India
| | - Anup K. Kesavan
- Department of Molecular Biology and Biochemistry, Guru Nanak Dev UniversityAmritsar, India
| | - Ashwani K. Thukral
- Plant Stress Physiology Lab, Department of Botanical and Environmental Sciences, Guru Nanak Dev UniversityAmritsar, India
| | - Renu Bhardwaj
- Plant Stress Physiology Lab, Department of Botanical and Environmental Sciences, Guru Nanak Dev UniversityAmritsar, India
| | - Pravej Alam
- Biology Department, College of Science and Humanities, Prince Sattam bin Abdulaziz UniversityAlkharj, Saudi Arabia
| | - Parvaiz Ahmad
- Department of Botany and Microbiology, Faculty of Science, King Saud UniversityRiyadh, Saudi Arabia
- Department of Botany, S. P. CollegeSrinagar, India
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18
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Wei Z, Li J. Brassinosteroids Regulate Root Growth, Development, and Symbiosis. MOLECULAR PLANT 2016; 9:86-100. [PMID: 26700030 DOI: 10.1016/j.molp.2015.12.003] [Citation(s) in RCA: 120] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/30/2015] [Revised: 10/29/2015] [Accepted: 12/07/2015] [Indexed: 05/19/2023]
Abstract
Brassinosteroids (BRs) are natural plant hormones critical for growth and development. BR deficient or signaling mutants show significantly shortened root phenotypes. However, for a long time, it was thought that these phenotypes were solely caused by reduced cell elongation in the mutant roots. Functions of BRs in regulating root development have been largely neglected. Nonetheless, recent detailed analyses, revealed that BRs are not only involved in root cell elongation but are also involved in many aspects of root development, such as maintenance of meristem size, root hair formation, lateral root initiation, gravitropic response, mycorrhiza formation, and nodulation in legume species. In this review, current findings on the functions of BRs in mediating root growth, development, and symbiosis are discussed.
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Affiliation(s)
- Zhuoyun Wei
- Ministry of Education Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou 730000, China
| | - Jia Li
- Ministry of Education Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou 730000, China.
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19
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Du J, Zhao B, Sun X, Sun M, Zhang D, Zhang S, Yang W. Identification and Characterization of Multiple Intermediate Alleles of the Key Genes Regulating Brassinosteroid Biosynthesis Pathways. FRONTIERS IN PLANT SCIENCE 2016; 7:1893. [PMID: 28138331 PMCID: PMC5238361 DOI: 10.3389/fpls.2016.01893] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/21/2016] [Accepted: 11/30/2016] [Indexed: 05/07/2023]
Abstract
Most of the early identified brassinosteroid signaling and biosynthetic mutants are null mutants, exhibiting extremely dwarfed phenotypes and male sterility. These null mutants are usually unable to be directly transformed via a routinely used Agrobacterium-mediated gene transformation system and therefore are less useful for genetic characterization of the brassinosteroid (BR)-related pathways. Identification of intermediate signaling mutants such as bri1-5 and bri1-9 has contributed drastically to the elucidation of BR signaling pathway using both genetic and biochemical approaches. However, intermediate mutants of key genes regulating BR biosynthesis have seldom been reported. Here we report identification of several intermediate BR biosynthesis mutants mainly resulted from leaky transcriptions due to the insertions of T-DNAs in the introns. These mutants are semi-dwarfed and fertile and capable to be transformed. These intermediate mutants could be useful tools for future discovery and analyses of novel components regulating BR biosynthesis and catabolism via genetic modifier screen.
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Affiliation(s)
- Junbo Du
- College of Agronomy, Sichuan Agricultural University, Sichuan Engineering Research Center for Crop Strip Intercropping SystemChengdu, China
- Ministry of Education Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou UniversityLanzhou, China
- *Correspondence: Junbo Du
| | - Baolin Zhao
- Ministry of Education Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou UniversityLanzhou, China
- Key Laboratory of Tropical Plant Resources and Sustainable Use, Xishuangbanna Tropical Botanical Garden, Chinese Academy of ScienceKunming, China
| | - Xin Sun
- College of Agronomy, Sichuan Agricultural University, Sichuan Engineering Research Center for Crop Strip Intercropping SystemChengdu, China
| | - Mengyuan Sun
- College of Agronomy, Sichuan Agricultural University, Sichuan Engineering Research Center for Crop Strip Intercropping SystemChengdu, China
| | - Dongzhi Zhang
- Ministry of Education Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou UniversityLanzhou, China
| | - Shasha Zhang
- Ministry of Education Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou UniversityLanzhou, China
| | - Wenyu Yang
- College of Agronomy, Sichuan Agricultural University, Sichuan Engineering Research Center for Crop Strip Intercropping SystemChengdu, China
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Kim MK, Jang MS, Youn JH, Son SH, Lee JE, Kim TW, Kim SK. Occurrence of phosphorylated castasterone in Arabidopsis thaliana and Lycopersicum esculentum. PHYSIOLOGIA PLANTARUM 2015; 153:58-67. [PMID: 24939035 DOI: 10.1111/ppl.12242] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/28/2013] [Revised: 03/20/2014] [Accepted: 05/14/2014] [Indexed: 06/03/2023]
Abstract
An in vitro enzyme assay using radioisotope-labeled (3) H-castasterone ((3) H-CS) or (32) P-ATP showed that CS can be phosphorylated by ATP in Arabidopsis and tomato plants. Gas chromatography-mass spectrometry (GC-MS) analysis using non-isotope-labeled CS and ATP revealed that the phosphorylation of CS occurs at the side chain, most likely at the C-23 hydroxyl. The polar fractions than free brassinosteroids (BRs) obtained from extracts of Arabidopsis and tomato showed almost no BRs activity in a rice lamina inclination bioassay. However, the fractions showed increased bioactivity after treatment with wheat germ acidic phosphatase (WGAP). Additionally, CS was identified from the hydrolysate by WGAP using GC-MS analysis in both plants. In contrast, the polar fractions obtained from BR-deficient mutants, Arabidopsis cyp85a2 and tomato d(x) , did not show an increase in biological activity with WGAP treatment, and no free BRs, including CS, were detected in the hydrolysate. This suggests that CS phosphate is a naturally occurring biologically inactive conjugate that is generated when CS is normally synthesized in Arabidopsis and tomato plants. Taken together, these results suggest that phosphorylation of CS is an important conjugation process for the maintenance of the homeostatic level of an active BR and thus the regulation of the growth and development of plants.
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Affiliation(s)
- Min Kyun Kim
- Department of Life Science, Chung-Ang University, Seoul, 156-756, Republic of Korea
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Saini S, Sharma I, Pati PK. Versatile roles of brassinosteroid in plants in the context of its homoeostasis, signaling and crosstalks. FRONTIERS IN PLANT SCIENCE 2015; 6:950. [PMID: 26583025 PMCID: PMC4631823 DOI: 10.3389/fpls.2015.00950] [Citation(s) in RCA: 96] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/13/2015] [Accepted: 10/18/2015] [Indexed: 05/18/2023]
Abstract
Brassinosteroids (BRs) are a class of steroidal plant hormones that play diverse roles in plant growth and developmental processes. Recently, the easy availability of biological resources, and development of new molecular tools and approaches have provided the required impetus for deeper understanding of the processes involved in BRs biosynthesis, transport, signaling and degradation pathways. From recent studies it is also evident that BRs interact with other phytohormones such as auxin, cytokinin, ethylene, gibberellin, jasmonic acid, abscisic acid, salicylic acid and polyamine in regulating wide range of physiological and developmental processes in plants. The inputs from these studies are now being linked to the versatile roles of BRs. The present review highlights the conceptual development with regard to BR homeostasis, signaling and its crosstalk with other phytohormones. This information will assist in developing predictive models to modulate various useful traits in plants and address current challenges in agriculture.
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