title: A wheat PI4K gene whose product possesses threonine autophophorylation activity confers tolerance to drought and salt in Arabidopsis.
abstract: Phosphoinositides are involved in regulation of recruitment and activity of signalling proteins in cell membranes. Phosphatidylinositol (PI) 4-kinases (PI4Ks) generate PI4-phosphate the precursor of regulatory phosphoinositides. No type II PI4K research on the abiotic stress response has previously been reported in plants. A stress-inducible type II PI4K gene, named TaPI4KIIγ, was obtained by de novo transcriptome sequencing of drought-treated wheat (Triticum aestivum). TaPI4KIIγ, localized on the plasma membrane, underwent threonine autophosphorylation, but had no detectable lipid kinase activity. Interaction of TaPI4KIIγ with wheat ubiquitin fusion degradation protein (TaUDF1) indicated that it might be hydrolysed by the proteinase system. Overexpression of TaPI4KIIγ revealed that it could enhance drought and salt stress tolerance during seed germination and seedling growth. A ubdkγ7 mutant, identified as an orthologue of TaPI4KIIγ in Arabidopsis, was sensitive to salt, polyethylene glycol (PEG), and abscisic acid (ABA), and overexpression of TaPI4KIIγ in the ubdkγ7 mutant compensated stress sensitivity. TaPI4KIIγ promoted root growth in Arabidopsis, suggesting that TaPI4KIIγ might enhance stress resistance by improving root growth. Overexpression of TaPI4KIIγ led to an altered expression level of stress-related genes and changes in several physiological traits that made the plants more tolerant to stress. The results provided evidence that overexpression of TaPI4KIIγ could improve drought and salt tolerance.
authors.affiliation: Institute of Crop Science, Chinese Academy of Agricultural Sciences (CAAS)/National Key Facility for Crop Gene Resources and Genetic Improvement, Beijing 100081, China.
authors.forename: Pei
authors.initials: P
authors.lastname: Liu
authors.forename: Zhao-Shi
authors.initials: ZS
authors.lastname: Xu
authors.forename: Lu
authors.initials: L
authors.lastname: Pan-Pan
authors.forename: Di
authors.initials: D
authors.lastname: Hu
authors.forename: Ming
authors.initials: M
authors.lastname: Chen
authors.forename: Lian-Cheng
authors.initials: LC
authors.lastname: Li
authors.forename: You-Zhi
authors.initials: YZ
authors.lastname: Ma
mesh_terms: D019870:1-Phosphatidylinositol 4-Kinase / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D017360:Arabidopsis / Q000235:genetics / Q000502:physiology*; D055864:Droughts; D015870:Gene Expression; D008969:Molecular Sequence Data; D010766:Phosphorylation; D010802:Phylogeny; D010940:Plant Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D030821:Plants, Genetically Modified / Q000235:genetics / Q000502:physiology*; D055049:Salt Tolerance; D012492:Salts / Q000378:metabolism; D012965:Sodium Chloride / Q000378:metabolism*; D013912:Threonine / Q000378:metabolism*; D014908:Triticum / Q000737:chemistry / Q000145:classification / Q000201:enzymology* / Q000235:genetics
chemical_list: D010940:Plant Proteins; D012492:Salts; D013912:Threonine; D012965:Sodium Chloride; D019870:1-Phosphatidylinositol 4-Kinase
keywords: Kinase activity; PI4K; Triticum aestivum.; overexpression; protein interaction; stress response