一氧化氮与细胞分裂素信号通路互作调节植物适应性生长的分子机制

Nitric oxide (NO) is stimulated by environmental cues involving in regulation of plant defense and stress responses, as well as plant growth and development. A major physiological effect of NO is executed by S-nitrosylation which is posttranslational modification involved in redox-based cellular signaling. S-nitrosylation, an NO group is covalently linked to the reactive Cys thiol of a protein to form an S-nitrosothiol (SNO), resulting in the biological function of targeted protein is interfered. The S-nitrosylation-regulated stress responses have been well studied. However, little is known about the mechanism of S-nitrosylation-regulated growth and development. In our previous studies, we found key components in the cytokinin signaling pathway could be specially S-nitrosylated. In the present study, we propose to investigate the molecular mechanism and the physiological significance of the NO repressing cytokinin signaling pathway via S-nitrosylation, aimed to understand the mechanism of plant adapting growth regulated by the crosstalk of NO signaling and cytokinin signaling.

一氧化氮(nitric oxide, NO)是环境刺激信号之一，参与植物的防御或胁迫反应，同时调节植物的生长发育。S-亚硝基化(S-nitrosylation)是NO发挥生理功能的主要方式之一，属于一种氧化还原依赖的蛋白翻译后修饰形式。它是通过NO与蛋白半胱氨酸残基的巯基共价结合，使巯基基团(SH)转化为亚硝基硫醇(SNO)的过程，进而调控靶蛋白的生物学活性。S-亚硝基化在植物防御反应与胁迫反应的调控机制有较系统的研究，但对其调控植物生长发育的生化和遗传机制知之甚少。我们前期的研究发现细胞分裂素信号通路中主要组分可被S-亚硝基化特异地修饰，因此本项目拟通过构建一系列的遗传材料，系统地研究细胞分裂素信号途径中主要组分S-亚硝基化的生化和生物学特征，阐述NO信号通路和细胞分裂素信号通路互作调控植物适应性生长的生化和分子机制。