干旱和高盐等逆境是限制植物产量的重要因素。因此，鉴定抗逆相关基因用于作物改良是未来抗逆育种的关键策略之一。MSR基因已在拟南芥和水稻等植物中克隆，但其作用机制未见报道。MSR能被多种非生物胁迫诱导表达，而且MSR可以清除机体内过量的ROS，也可以体外催化因ROS氧化的R和S型MetSO的还原，暗示其在植物胁迫应答中发挥作用。申请人从体细胞渐渗系耐盐新品种SR3中克隆了非生物胁迫响应基因TaMSRB3.1和TaMSRA4.1，其在拟南芥和小麦中过表达能提高耐盐、抗旱、抗氧化能力。本申请拟系统并首次克隆小麦MSR基因家族，揭示TaMSRB3.1和TaMSRA4.1的在非生物胁迫下的响应特征，鉴定其体内底物，研究该基因调控的下游基因及其与ABA和ROS途径的关联，发现调控TaMsrB3.1和TaMsrA4.1表达的重要转录因子，初步阐明其在应答非生物胁迫的作用机制。

Drought and high salinity are important factors limiting growth and yield of plant. Therefore, it is one of the key strategies in the future to characterize more abiotic resistance related genes for crop improvement. It was not reported about the molecular mechanism of MSR gene although its family has been cloned from Arabidopsis and rice. MSR genes can be induced by various abiotic stresses, and MSR can clear the excess ROS in plant cell, and also can catalyze the reduction of R and S MetSO (free and peptide) oxidized by ROS in vitro, suggesting they could play important roles in stress response. We characterized two abiotic stress-induced MSR genes, TaMSRB3.1 and TaMSRA4.1, from a wheat somatic hybridid cv.SR3 with high salt resistance, and found that overexpression of them in Arabidopsis and wheat could enhance their abiotic stress tolerance. In this project, we will clone MSR gene family and detect the response profiles of TaMSRB3.1 and TaMSRA4.1 to various abiotic stresses, characterize their substrates, identify the important genes regulated by TaMsrB3.1 and TaMsrA4.1, discover the relationship between them and ROS/ABA pathways, and isolate transcripnal factors regulating the expression of TaMSRB3.1 and TaMSRA4.1. It will primarily elucidate the underlying mechanism of MSR genes in abiotic stress tolerance in plants.