CRP小肽OsDT11调控水稻抗旱性的分子机理研究

Drought stress has become one of the most important factors that limits the yield and quality improvement of rice. CRP plays roles in multiple processes in plants, however, the function and mechanism of CRP in drought resistance are not yet clear. Our previous study reveals that overexpression of OsDT11, which encodes a CRP, could improve the drought resistant in rice, while the drought tolerance of knockdown lines decreased. In this study, the following content will be analyzed: (1) We proposed to figure the ABA biosynthesis factors regulated by OsDT11-mediated drought tolerance; (2) By transformation of construction vectors containing truncated and mutational OsDT11, the function motif and critical sites of OsDT11 will be characterized; (3) We plan to identify the interaction protein of OsDT11 by high-throughput sequencing and two-yeast hybrid. This project will significantly help us to learn about the mechanism of drought resistance in rice and the function of CRP in plants and contribute to resistant breeding programs of rice.

干旱胁迫是制约水稻产量和品质提高的重要因素之一。研究水稻抗旱机制，培育抗旱品种，是克服水稻干旱胁迫的有效途径。课题组前期研究表明，以水稻中花11为亲本，过量表达OsDT11（CRP小肽）能使水稻耐旱性显著增强，ABA含量明显上升；而抑制OsDT11表达的转基因株系耐旱性明显降低，且植株失水率与OsDT11表达量呈现显著相关。说明OsDT11是调控水稻抗旱的重要因子。本项目拟应用CRISPR/Cas9技术、转录组表达谱分析、酵母双杂交、水稻遗传转化等手段研究：（1）OsDT11如何调节ABA生物合成从而介导水稻抗旱的分子机理；（2）OsDT11小肽作用的功能结构域及关键调控位点；（3）鉴定受OsDT11调控的抗旱关键基因，绘制OsDT11调控水稻抗旱的信号通路。通过上述研究，明确OsDT11调控水稻抗旱的分子机制，解析CRP小肽参与调节植物抗旱的新功能，并为水稻抗旱分子育种提供重要理论依据。

作为全世界最重要的粮食作物之一，水稻对干旱胁迫非常敏感，干旱胁迫已经成为制约水稻产量和品质提高的重要因素之一。研究水稻抗旱机制，培育抗旱品种，是克服水稻干旱胁迫的有效途径。按照课题设计思路，在前期发现过量表达CRP小肽OsDT11能够显著提高水稻耐旱性的基础上，应用转录组表达谱分析、荧光定量PCR等技术研究了：（1）OsDT11能够调控ABA含量及植株对ABA的敏感性；（2）OsDT11小肽的C端第三个半胱氨酸是其关键功能位点；（3）OsDT11参与了与水稻抗旱相关的多种信号通路；（4）OsDT11能够调控下游关键基因的表达。本项研究将为人们理解水稻抗旱机制、解析CRP小肽调节植物抗旱的新功能提供重要信息，并为通过基因工程创制水稻抗旱新品种提供重要借鉴。通过课题的实施，发表SCI论文3篇，培养硕士研究生3名，较好地完成了课题任务。