title: The Wheat GT Factor TaGT2L1D Negatively Regulates Drought Tolerance and Plant Development.
abstract: GT factors are trihelix transcription factors that specifically regulate plant development and stress responses. Recently, several GT factors have been characterized in different plant species; however, little is known about the role of GT factors in wheat. Here, we show that TaGT2L1A, TaGT2L1B, and TaGT2L1D are highly homologous in hexaploid wheat, and are localized to wheat chromosomes 2A, 2B, and 2D, respectively. These TaGT2L1 genes encode proteins containing two SANT domains and one central helix. All three homologs were ubiquitously expressed during wheat development and were responsive to osmotic stress. Functional analyses demonstrated that TaGT2L1D acts as a transcriptional repressor; it was able to suppress the expression of AtSDD1 in Arabidopsis by binding directly to the GT3 box in its promoter that negatively regulates drought tolerance. TaGT2L1D overexpression markedly increased the number of stomata and reduced drought tolerance in gtl1-3 plants. Notably, ectopic expression of TaGT2L1D also affected floral organ development and overall plant growth. These results demonstrate that TaGT2L1 is an ortholog of AtGTL1, and that it plays an evolutionarily conserved role in drought resistance by fine tuning stomatal density in wheat. Our data also highlight the role of TaGT2L1 in plant growth and development.
authors.affiliation: Center for Agricultural Resources Research, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Shijiazhuang, Hebei 050021, P. R. China.|University of Chinese Academy of Sciences, Beijing 100049, P. R. China.
authors.forename: Xin
authors.initials: X
authors.lastname: Zheng
authors.affiliation: School of Agriculture, Food and Wine, University of Adelaide, Waite Research Institute, Glen Osmond, SA 5064, Australia.
authors.forename: Haipei
authors.initials: H
authors.lastname: Liu
authors.affiliation: State Key Laboratory of Agricultural Microbiology, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, 430070, P. R. China.
authors.forename: Hongtao
authors.initials: H
authors.lastname: Ji
authors.affiliation: State Key Laboratory of Agricultural Microbiology, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, 430070, P. R. China.
authors.forename: Youning
authors.initials: Y
authors.lastname: Wang
authors.affiliation: Center for Agricultural Resources Research, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Shijiazhuang, Hebei 050021, P. R. China.
authors.forename: Baodi
authors.initials: B
authors.lastname: Dong
authors.affiliation: Center for Agricultural Resources Research, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Shijiazhuang, Hebei 050021, P. R. China.
authors.forename: Yunzhou
authors.initials: Y
authors.lastname: Qiao
authors.affiliation: Center for Agricultural Resources Research, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Shijiazhuang, Hebei 050021, P. R. China.
authors.forename: Mengyu
authors.initials: M
authors.lastname: Liu
authors.affiliation: State Key Laboratory of Agricultural Microbiology, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, 430070, P. R. China.
authors.forename: Xia
authors.initials: X
authors.lastname: Li
mesh_terms: D000595:Amino Acid Sequence; D017360:Arabidopsis / Q000235:genetics* / Q000254:growth & development / Q000378:metabolism; D029681:Arabidopsis Proteins / Q000235:genetics* / Q000378:metabolism; D032461:Chromosomes, Plant / Q000737:chemistry; D017124:Conserved Sequence; D055864:Droughts; D018507:Gene Expression Regulation, Developmental; D018506:Gene Expression Regulation, Plant; D009997:Osmotic Pressure; D063245:Plant Development / Q000235:genetics*; D054046:Plant Stomata / Q000502:physiology; D011003:Ploidies; D020033:Protein Isoforms / Q000235:genetics / Q000378:metabolism; D016415:Sequence Alignment; D017386:Sequence Homology, Amino Acid; D013312:Stress, Physiological / Q000235:genetics; D014157:Transcription Factors / Q000235:genetics* / Q000378:metabolism; D014908:Triticum / Q000235:genetics* / Q000254:growth & development / Q000378:metabolism
chemical_list: D029681:Arabidopsis Proteins; C579611:GT2L protein, Arabidopsis; D020033:Protein Isoforms; D014157:Transcription Factors