OsMAPK6调控水稻光呼吸代谢的机制及其功能研究

光呼吸是植物中仅次于光合作用的第二大代谢流，它与植物多种生理过程紧密相关, 但其调控分子机制研究至今仍很滞后。申请人近期发现水稻丝裂原活化蛋白激酶6（OsMAPK6）敲除突变体的光呼吸速率及相关代谢物含量均显著降低。进一步检测结果显示，Osmapk6突变体中光呼吸关键酶活力下降，同时光呼吸关键酶还存在磷酸化修饰且可与OsMAPK6发生互作，暗示OsMAPK6可能从转录表达水平及翻译后修饰水平双向调控光呼吸代谢。本项目拟在进一步确认OsMAPK6对光呼吸的调控功能的基础上，深入探究其调控位点及调控分子机理，同时深入解析光呼吸在水稻光合调控与逆境响应中的功能。本项目有助于更新我们对光呼吸代谢调控机制的认识，并为作物遗传改良提供新的基因资源和理论指导。

Photorespiration is the second highest metabolite flux in plants behind photosynthesis, and it is closely related to various biological processes of plants, but its regulatory mechanism is far from clear. Our recent studies found that photorespiration rate of the Osmapk6 knockout mutant was significantly declined, and contents of the photorespiration metabolites were correspondingly decreased. Furthermore, activities of some enzymes functioning in photorespiration were down-regulated, in addition, OsMAPK6 interacted with some photorespiration proteins. These results suggested that OsMAPK6 may be able to regulate photorespiration at both transcription and post-translational levels. Based on our preliminary results, this project aims to further explore the photorespiration regulatory sites by OsMAPK6, and further dissect the mechanisms of how OsMAPK6 regulates photorespiration rate, eventually to understand the function of this process in photosynthesis regulation and stress resistance. This study will hopefully gain new insight into regulation and physiological functions of photorespiration, which may also provide theoretical and technical support for crop improvements.