云南高原粳稻区，山多地少，水资源时空分布不均，是我国旱灾频发地区之一。因此，系统研究水稻干旱胁迫调节的分子机制对于保障云南稻区粮食安全具有重要意义，而SAPK2蛋白激酶是水稻干旱胁迫响应中的关键调节因子。在之前研究中，我们发现SAPK2蛋白激酶在水稻干旱胁迫响应中发挥正调节作用，但是SAPK2蛋白激酶调控水稻干旱胁迫响应的具体分子机制有待进一步研究。前期研究中我们发现，干旱处理下，sapk2突变体结实率明显下降。进而对SAPK2的磷酸化底物进行筛选和初步验证发现，SAPK2蛋白激酶与OsWPP蛋白可以相互作用。以上结果暗示SAPK2蛋白激酶可能通过与OsWPP蛋白互作，共同调控水稻干旱胁迫响应，并影响干旱胁迫下的水稻产量。在以上工作的基础上，本项目将系统地研究SAPK2蛋白激酶与OsWPP蛋白互作共同调控水稻干旱胁迫响应的分子机制，从而完善SAPK2蛋白激酶调控植物干旱胁迫的信号转导网络。

The Yunnan Plateau is one of the japonica rice areas. Because of less cultivated lands in the mountains and unevenly distribution of the water resources in time and space, it is one of the frequent drought areas in China. Therefore, systematic studying on the molecular mechanism of rice drought stress regulation has great significance for ensuring food security in Yunnan rice region, and SAPK2 protein kinase is the key regulator in rice drought stress signaling. In previous studies, we found that SAPK2 protein kinase function as positive regulators of drought stress response in rice,but the molecular mechanism of SAPK2 protein kinase regulating drought stress response in rice needs further study. In the preliminary study of this project, we found that under drought treatment, the seed setting rate of sapk2 mutant significantly decreased. Furthermore, screening and preliminary verification of SAPK2 phosphorylation substrate revealed that SAPK2 protein kinase interacts with OsWPP protein. These results suggest that SAPK2 protein kinase may interact with OsWPP protein to regulate rice drought stress response and affect rice yield under drought stress. Based on above works, this project will systematically study the molecular mechanism of the interaction between SAPK2 protein kinase and OsWPP protein to regulate rice drought stress response, so as to improve the signal transduction network of SAPK2 protein kinase regulating plant drought stress.