水稻PPR家族蛋白EMS19在温敏核不育中的功能研究

温敏不育突变体在作物两系法杂交制种的关键。目前水稻中有数个温敏核不育位点被克隆，但其遗传和分子机制仍有待阐明。在前期工作中，我们在揭示了模式植物中一个普遍的温敏育性转换机制，同时也获得了一个新的水稻温敏不育突变体ems19，该突变体呈现高温不育，低温育性恢复的表型。在本项目中，我们将以该突变体为基础，展开以下研究：1）通过细胞学手段阐明高温对ems19突变体花药和花粉发育的影响；2）利用分子和生化手段揭示编码PPR家族蛋白的EMS19基因在温敏核不育中的功能机理和作用网络；3）阐明低温恢复ems19育性的的分子机制，验证其作为新的温敏遗传位点在生产上的应用潜力。本项目的完成将为两系杂交育种生产实践提供基础依据和技术支持。

Thermo-sensitive male-sterile (TGMS) mutants play an essential role in two-line breeding system. Until now, several thermos-sensitive genetic loci have been cloned in rice but the underlying mechanism remains elusive. In the previous study, we had revealed a general mechanism of the sterility-fertility conversion in Arabidopsis. We also obtained a new TGMS mutant in rice and named ems19, which is male-sterile at high temperature while is male-fertile at low temperature. In this project, based on the analysis of ems19, we mainly focus on the research into the following ways: 1) to elucidate how the anther and pollen development of ems19 is affected under high temperature via the cytological observation; 2) to show the biological function and molecular pathway of EMS19 which encodes a PPR protein; 3) to reveal the molecular mechanism of fertility restoration of ems19 under low temperature, which may provide a potential for hybrid breeding as a new thermos-sensitive genetic locus. Therefore, this project will provide a basic theory and a technical support for the application of two-line breeding system.