大豆MAPK蛋白激酶在Dof转录因子介导的ROS清除中的作用机制解析

大豆是我国重要的油料作物之一，然而干旱和盐害等非生物胁迫严重影响大豆的产量和品质。本课题从大豆中筛选到Dof转录因子基因GmDof41，过表达该基因能提高大豆的抗旱耐盐性。GmDof41受到GmDREB1B;1的直接调控表达，而GmDof41又直接调控GmDREB2A的表达，激活ROS信号通路，增强植株体内ROS的清除能力，从而提高植物对胁迫的抗性。进一步研究发现，MAPK蛋白激酶GmMPK3能磷酸化GmDof41。植物MAPK蛋白激酶和Dof转录因子所介导的信号途径在植物响应非生物胁迫中具有重要作用，但相关作用机制却鲜有报道。本研究旨在阐明大豆GmDof41介导的信号网络在ROS清除中的作用机理；探讨GmMPK3对GmDof41的磷酸化作用机理，明确磷酸化关系对于植物响应外界胁迫的重要性，这对深入了解大豆抗旱耐盐分子机制有重要意义。

Soybean is one of the most important oil crops in China, but abiotic stresses such as drought and salt damage seriously affect the yield and quality of soybean. In this study, the overexpression of Dof transcription factor gene GmDof41 from soybean can improve the drought and salt tolerance of soybean. GmDof41 is directly regulated by GmDREB1B;1, while GmDof41 directly regulates the expression of GmDREB2A, activates ROS signaling pathway, and enhances the ability of ROS scavenging in plants, thus improving plant resistance to stress. Further study showed that MAPK protein kinase GmMPK3 could phosphorylate GmDof41. Signal pathways mediated by plant MAPK protein kinases and Dof transcription factors play an important role in plant response to abiotic stress, but the related mechanisms are rarely reported. The purpose of this study is to clarify the mechanism of soybean GmDof41-mediated signal network in ROS scavenging, to explore the mechanism of GmMPK3 phosphorylation on GmDof41, and to clarify the importance of phosphorylation relationship for plant response to external stress, which is of great significance for further understanding the molecular mechanism of drought and salt tolerance in soybean.