title: Control of cotton fibre elongation by a homeodomain transcription factor GhHOX3.
abstract: Cotton fibres are unusually long, single-celled epidermal seed trichomes and a model for plant cell growth, but little is known about the regulation of fibre cell elongation. Here we report that a homeodomain-leucine zipper (HD-ZIP) transcription factor, GhHOX3, controls cotton fibre elongation. GhHOX3 genes are localized to the 12th homoeologous chromosome set of allotetraploid cotton cultivars, associated with quantitative trait loci (QTLs) for fibre length. Silencing of GhHOX3 greatly reduces (>80%) fibre length, whereas its overexpression leads to longer fibre. Combined transcriptomic and biochemical analyses identify target genes of GhHOX3 that also contain the L1-box cis-element, including two cell wall loosening protein genes GhRDL1 and GhEXPA1. GhHOX3 interacts with GhHD1, another homeodomain protein, resulting in enhanced transcriptional activity, and with cotton DELLA, GhSLR1, repressor of the growth hormone gibberellin (GA). GhSLR1 interferes with the GhHOX3-GhHD1 interaction and represses target gene transcription. Our results uncover a novel mechanism whereby a homeodomain protein transduces GA signal to promote fibre cell elongation.
authors.affiliation: National Key Laboratory of Plant Molecular Genetics, National Plant Gene Research Center, Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200032, China.
authors.forename: Chun-Min
authors.initials: CM
authors.lastname: Shan
authors.affiliation: National Key Laboratory of Plant Molecular Genetics, National Plant Gene Research Center, Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200032, China.
authors.forename: Xiao-Xia
authors.initials: XX
authors.lastname: Shangguan
authors.affiliation: National Key Laboratory of Plant Molecular Genetics, National Plant Gene Research Center, Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200032, China.
authors.forename: Bo
authors.initials: B
authors.lastname: Zhao
authors.affiliation: National Key Laboratory of Plant Molecular Genetics, National Plant Gene Research Center, Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200032, China.
authors.forename: Xiu-Fang
authors.initials: XF
authors.lastname: Zhang
authors.affiliation: National Key Laboratory of Plant Molecular Genetics, National Plant Gene Research Center, Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200032, China.
authors.forename: Lu-Men
authors.initials: LM
authors.lastname: Chao
authors.affiliation: National Key Laboratory of Plant Molecular Genetics, National Plant Gene Research Center, Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200032, China.
authors.forename: Chang-Qing
authors.initials: CQ
authors.lastname: Yang
authors.affiliation: National Key Laboratory of Plant Molecular Genetics, National Plant Gene Research Center, Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200032, China.
authors.forename: Ling-Jian
authors.initials: LJ
authors.lastname: Wang
authors.affiliation: National Key Laboratory of Crop Genetics &Germplasm Enhancement, MOE Hybrid Cotton R&D Engineering Research Center, Nanjing Agricultural University, Nanjing 210095, China.
authors.forename: Hua-Yu
authors.initials: HY
authors.lastname: Zhu
authors.affiliation: National Key Laboratory of Crop Genetics &Germplasm Enhancement, MOE Hybrid Cotton R&D Engineering Research Center, Nanjing Agricultural University, Nanjing 210095, China.
authors.forename: Yan-Da
authors.initials: YD
authors.lastname: Zeng
authors.affiliation: National Key Laboratory of Crop Genetics &Germplasm Enhancement, MOE Hybrid Cotton R&D Engineering Research Center, Nanjing Agricultural University, Nanjing 210095, China.
authors.forename: Wang-Zhen
authors.initials: WZ
authors.lastname: Guo
authors.affiliation: National Key Laboratory of Crop Genetics &Germplasm Enhancement, MOE Hybrid Cotton R&D Engineering Research Center, Nanjing Agricultural University, Nanjing 210095, China.
authors.forename: Bao-Liang
authors.initials: BL
authors.lastname: Zhou
authors.affiliation: Department of Ecology, Evolution and Organismal Biology, Iowa State University, Ames, Iowa 50011, USA.
authors.forename: Guan-Jing
authors.initials: GJ
authors.lastname: Hu
authors.affiliation: 1] National Key Laboratory of Crop Genetics &Germplasm Enhancement, MOE Hybrid Cotton R&D Engineering Research Center, Nanjing Agricultural University, Nanjing 210095, China [2] Department of Molecular Biosciences, Center for Computational Biology and Bioinformatics, and Institute for Cellular and Molecular Biology, The University of Texas at Austin, Austin, Texas 78712, USA.
authors.forename: Xue-Ying
authors.initials: XY
authors.lastname: Guan
authors.affiliation: 1] National Key Laboratory of Crop Genetics &Germplasm Enhancement, MOE Hybrid Cotton R&D Engineering Research Center, Nanjing Agricultural University, Nanjing 210095, China [2] Department of Molecular Biosciences, Center for Computational Biology and Bioinformatics, and Institute for Cellular and Molecular Biology, The University of Texas at Austin, Austin, Texas 78712, USA.
authors.forename: Z Jeffrey
authors.initials: ZJ
authors.lastname: Chen
authors.affiliation: Department of Ecology, Evolution and Organismal Biology, Iowa State University, Ames, Iowa 50011, USA.
authors.forename: Jonathan F
authors.initials: JF
authors.lastname: Wendel
authors.affiliation: National Key Laboratory of Crop Genetics &Germplasm Enhancement, MOE Hybrid Cotton R&D Engineering Research Center, Nanjing Agricultural University, Nanjing 210095, China.
authors.forename: Tian-Zhen
authors.initials: TZ
authors.lastname: Zhang
authors.affiliation: 1] National Key Laboratory of Plant Molecular Genetics, National Plant Gene Research Center, Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200032, China [2] Plant Science Research Center, Shanghai Chenshan Botanical Garden, Shanghai 201602, China.
authors.forename: Xiao-Ya
authors.initials: XY
authors.lastname: Chen
mesh_terms: D032561:Cotton Fiber; D020869:Gene Expression Profiling; D018507:Gene Expression Regulation, Developmental; D018506:Gene Expression Regulation, Plant; D005875:Gibberellins / Q000378:metabolism; D003368:Gossypium / Q000254:growth & development*; D006655:Histone Deacetylases / Q000378:metabolism; D018398:Homeodomain Proteins / Q000378:metabolism*; D016350:Leucine Zippers / Q000502:physiology*; D008969:Molecular Sequence Data; D010937:Plant Growth Regulators / Q000378:metabolism; D010940:Plant Proteins / Q000378:metabolism*; D040641:Quantitative Trait Loci; D064201:Trichomes / Q000254:growth & development*
chemical_list: D005875:Gibberellins; D018398:Homeodomain Proteins; D010937:Plant Growth Regulators; D010940:Plant Proteins; C007842:gibberellic acid; D006655:Histone Deacetylases