title: Wheat bHLH-type transcription factor gene TabHLH1 is crucial in mediating osmotic stresses tolerance through modulating largely the ABA-associated pathway.
abstract: Wheat bHLH family gene TabHLH1 is responsive to drought and salt stresses, and it acts as one crucial regulator in mediating tolerance to aforementioned stresses largely through an ABA-associated pathway. Osmotic stresses are adverse factors for plant growth and crop productivity. In this study, we characterized TabHLH1, a gene encoding wheat bHLH-type transcription factor (TF) protein, in mediating plant adaptation to osmotic stresses. TabHLH1 protein contains a conserved basic-helix-loop-helix (bHLH) domain shared by its plant counterparts. Upon PEG-simulated drought stress, salt stress, and exogenous abscisic acid (ABA), the TabHLH1 transcripts in roots and leaves were induced. Under PEG-simulated drought stress and salt stress treatments, the tobacco seedlings with TabHLH1 overexpression exhibited improved growth and osmotic stress-associated traits, showing increased biomass and reduced leaf water loss rate (WLR) relative to wild type (WT). The transgenic lines also possessed promoted stomata closure under drought stress, salt stress, and exogenous ABA and increased proline and soluble sugar contents and reduced hydrogen peroxide (H2O2) amount under osmotic stress conditions, indicating that TabHLH1-mediated osmolyte accumulation and cellular ROS homeostasis contributed to the drought stress and salt stress tolerance. NtPYL12 and NtSAPK2;1, the genes encoding ABA receptor and SnRK2 family kinase, respectively, showed up-regulated expression in lines overexpressing TabHLH1 under osmotic stress and exogenous ABA conditions; overexpression of them conferred plants modified stomata movement, leaf WLR, and growth feature under drought and high salinity, suggesting that these ABA-signaling genes are mediated by wheat TabHLH1 gene and involved in regulating plant responses to simulated drought and salt stresses. Our investigation indicates that the TabHLH1 gene plays critical roles in plant tolerance to osmotic stresses largely through an ABA-dependent pathway.
authors.affiliation: College of Life Sciences, Agricultural University of Hebei, Baoding, 071001, China.
authors.forename: Tongren
authors.initials: T
authors.lastname: Yang
authors.affiliation: College of Life Sciences, Agricultural University of Hebei, Baoding, 071001, China.|Key Laboratory of Crop Growth Regulation of Hebei Province, Baoding, China.
authors.forename: Sufei
authors.initials: S
authors.lastname: Yao
authors.affiliation: College of Agronomy, Agricultural University of Hebei, Baoding, 071001, China.|College of Life Sciences, Agricultural University of Hebei, Baoding, 071001, China.
authors.forename: Lin
authors.initials: L
authors.lastname: Hao
authors.affiliation: College of Agronomy, Agricultural University of Hebei, Baoding, 071001, China.|Key Laboratory of Crop Growth Regulation of Hebei Province, Baoding, China.
authors.forename: Yuanyuan
authors.initials: Y
authors.lastname: Zhao
authors.affiliation: College of Life Sciences, Agricultural University of Hebei, Baoding, 071001, China. luwenjing@sohu.com.
authors.forename: Wenjing
authors.initials: W
authors.lastname: Lu
authors.affiliation: College of Agronomy, Agricultural University of Hebei, Baoding, 071001, China. xiaokai@hebau.edu.cn.|Key Laboratory of Crop Growth Regulation of Hebei Province, Baoding, China. xiaokai@hebau.edu.cn.
authors.forename: Kai
authors.initials: K
authors.lastname: Xiao
mesh_terms: D000040:Abscisic Acid / Q000378:metabolism* / Q000494:pharmacology; D000222:Adaptation, Physiological / Q000187:drug effects / Q000235:genetics*; D051778:Basic Helix-Loop-Helix Leucine Zipper Transcription Factors / Q000235:genetics* / Q000378:metabolism; D018533:Biomass; D018506:Gene Expression Regulation, Plant / Q000187:drug effects; D017343:Genes, Plant; D006861:Hydrogen Peroxide / Q000378:metabolism; D009997:Osmotic Pressure / Q000502:physiology*; D010641:Phenotype; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism; D018517:Plant Roots / Q000187:drug effects / Q000235:genetics / Q000502:physiology; D054046:Plant Stomata / Q000187:drug effects / Q000235:genetics / Q000502:physiology; D018526:Plant Transpiration / Q000187:drug effects / Q000235:genetics; D030821:Plants, Genetically Modified; D036226:Seedlings / Q000187:drug effects / Q000235:genetics / Q000502:physiology; D015398:Signal Transduction / Q000187:drug effects / Q000235:genetics; D013312:Stress, Physiological / Q000187:drug effects / Q000235:genetics*; D014026:Nicotiana / Q000235:genetics; D014908:Triticum / Q000187:drug effects / Q000235:genetics* / Q000502:physiology*; D015854:Up-Regulation / Q000187:drug effects / Q000235:genetics; D014867:Water / Q000378:metabolism
chemical_list: D051778:Basic Helix-Loop-Helix Leucine Zipper Transcription Factors; D010940:Plant Proteins; D014867:Water; D000040:Abscisic Acid; D006861:Hydrogen Peroxide
keywords: ABA signaling; Growth trait; Osmotic stress; Stomata movement; Wheat (Triticum aestivum L.); bHLH-type transcription factor