title: Differential Activation of the Wheat SnRK2 Family by Abiotic Stresses.
abstract: Plant responses to stress occur via abscisic acid (ABA) dependent or independent pathways. Sucrose non-fermenting1-related protein kinase 2 (SnRK2) play a key role in plant stress signal transduction pathways. It is known that some SnRK2 members are positive regulators of ABA signal transduction through interaction with group A type 2C protein phosphatases (PP2Cs). Here, 10 SnRK2s were isolated from wheat. Based on phylogenetic analysis using kinase domains or the C-terminus, the 10 SnRK2s were divided into three subclasses. Expression pattern analysis revealed that all TaSnRK2s were involved in the responses to PEG, NaCl, and cold stress. TaSnRK2s in subclass III were strongly induced by ABA. Subclass II TaSnRK2s responded weakly to ABA, whereas TaSnRK2s in subclass I were not activated by ABA treatment. Motif scanning in the C-terminus indicated that motifs 4 and 5 in the C-terminus were unique to subclass III. We further demonstrate the physical and functional interaction between TaSnRK2s and a typical group A PP2C (TaABI1) using Y2H and BiFC assays. The results showed that TaABI1 interacted physically with subclass III TaSnRK2s, while having no interaction with subclasses I and II TaSnRK2s. Together, these findings indicated that subclass III TaSnRK2s were involved in ABA regulated stress responses, whereas subclasses I and II TaSnRK2s responded to various abiotic stressors in an ABA-independent manner.
authors.affiliation: Key Laboratory for Cultivation of Tobacco Industry, College of Tobacco Science, Henan Agricultural University Zhengzhou, China.
authors.forename: Hongying
authors.initials: H
authors.lastname: Zhang
authors.affiliation: College of Plant Science and Technology, Key Laboratory of New Technology in Agricultural Application, Beijing University of Agriculture Beijing, China.
authors.forename: Weiyu
authors.initials: W
authors.lastname: Li
authors.affiliation: The National Key Facility for Crop Gene Resources and Genetic Improvement, Institute of Crop Science - Chinese Academy of Agricultural Sciences Beijing, China.
authors.forename: Xinguo
authors.initials: X
authors.lastname: Mao
authors.affiliation: The National Key Facility for Crop Gene Resources and Genetic Improvement, Institute of Crop Science - Chinese Academy of Agricultural Sciences Beijing, China.
authors.forename: Ruilian
authors.initials: R
authors.lastname: Jing
authors.affiliation: Key Laboratory for Cultivation of Tobacco Industry, College of Tobacco Science, Henan Agricultural University Zhengzhou, China.
authors.forename: Hongfang
authors.initials: H
authors.lastname: Jia
keywords: ABA signaling; TaSnRK2s; Triticum aestivum; abiotic stress; gene expression; protein–protein interaction