类受体酪氨酸激酶STRK1调控水稻耐盐性的分子机制

水稻耐盐性研究及耐盐品种选育对提高我国粮食产量、保障粮食安全意义重大。我们前期研究发现一个新的类受体胞质激酶STRK1能磷酸化CatC的Tyr210而正调控水稻耐盐性，且STRK1是迄今发现唯一能磷酸化CAT的酪氨酸残基的激酶，但其介导的盐胁迫信号转导通路与分子机制仍有待阐明。据此，课题拟开展以下主要研究：(1) 筛选鉴定与STRK1互作的RLK，解析其介导的盐胁迫信号跨膜转导机制；(2) 鉴定RLK-STRK1-CATs通路中关键酪氨酸磷酸化位点，阐明酪氨酸级联磷酸化特性及其在信号转导通路中的作用；(3) 鉴定和评价信号转导骨干成员RLK、STRK1和CATs的等位变异，分析其在耐盐品种培育中的应用价值。本项目旨在确立RLK-STRK1-CATs的信号转导完整通路，解析STRK1介导的盐胁迫信号转导的精细分子机制，为水稻耐盐品种的选育提供理论指导和耐盐的特征性分子标记。

Studying on the tolerance to salt stress and breeding new varieties with higher tolerance to salt stress in rice are of great significance for improving grain production and ensuring food safety in China. Our previous studies found that a novel receptor-like cytoplasmic kinase STRK1 could phosphorylate CatC at Tyr210 to positively regulate the salt tolerance in rice, and STRK1 is the only kinase that has been found so far to phosphorylate the tyrosine residues of CAT. Whereas, the pathway and molecular mechanism of salt signal transduction mediated by STRK1 remain to be elucidated. Accordingly, the following main researches will be carried out in this project: (1) Screening and identification of RLK that can interact with STRK1 to illustrate the mechanism of salt signal transmembrane transduction; (2) Identification of the key phospho-tyrosine sites at the RLK-STRK1-CATs pathway to elucidate the characteristics and roles of tyrosine phosphorylation cascade in salt stress signal transduction pathway; (3) Identification and evaluation the allele variations of RLK, STRK1 and CATs as the backbone members of signal transduction, and analysis of their potential application values. The aims of this project are to establish a complete signal transduction pathway of RLK-STRK1-CATs, to reveal the fine molecular mechanism of salt signal transduction mediated by STRK1, and to provide theoretical guidance and characteristic molecular markers of salt tolerance for breeding of salt tolerant crop varieties.