植物的发育进程受到可逆的蛋白质泛素化修饰，从而保持植物体内蛋白水平的平衡。研究这种修饰过程对揭示植物胁迫响应的调控规律具有重要意义。本实验室发现的E3泛素连接酶AtARRE通过泛素化修饰植物ABA信号途径中关键因子ABI5来影响植物的逆境应答，而另外一个E3泛素连接酶AtTRE1通过泛素化修饰与植物热胁迫响应的关键因子DREB2A来调控植物对高温的应答，却不受ABA水平变化的影响。本项目拟通过对AtARRE泛素化修饰ABI5的研究，明确泛素化修饰在ABA信号传递过程中的重要作用；通过对AtTRE1泛素化降解DREB2A，从而调控DRE2A内稳态的研究，揭示泛素化修饰在热胁迫应答过程中的调控作用。对E3泛素连接酶泛素化修饰植物体内重要抗逆途径的核心信号因子调控机制的研究，有助于揭示植物平衡“逆境应答”和“生长发育”这两大生物学过程的分子机理。

The developmental processes of plants are modified by ubiquitination that is important to keep the homeostasis of the protein level in the plants. This study is significance to unravel the regulatory mechanism of the stress response in plants. Our laboratory found that an E3 ligase AtARRE could ubiquitylate ABI5, the key factor in ABA signaling, to influence the stress response of plants. Another E3 ligase AtTRE1 could ubiquitylate DREB2A, the key transcriptional factor related to thermo-resistance in plants, to regulate the temperature response of plants. This process is independent of ABA. In this project, we want to characterize the ubiquitylation of ABI5 by AtARRE and to definite the importance of Ub-modification in ABA signaling pathway; we want to study the degradation of DREB2A by AtTRE1 and to reveal the regulation of Ub-modification in temperature response of plants. The study of Ub-modification of the key signaling factors in stress response is helpful to understand the balance between the stress response and the development of plants.