休眠基因RDO5的抑制因子SUR1和SUR2调控种子休眠的分子机制

种子休眠确保种子在最适宜的条件下萌发，对植物体的生存、延续和进化起着积极的作用。种子休眠的强弱关系到种子穗发芽、萌发率、整齐度及后续生长，对作物的产量和品质十分重要。RDO5是一个最新克隆、特异影响种子休眠的基因，通过不依赖ABA途径特异影响种子休眠。前期研究发现RDO5可能通过对种子中存储mRNA的调节和存储蛋白修饰来调节种子休眠，但是其具体途径和分子机制还很不清楚。本项目计划EMS诱变完全丧失休眠的突变体rdo5-2，获得休眠表型完全或部分恢复的突变体。然后通过全基因DNA测序和SNP关联分析克隆rdo5-2抑制因子、调节种子休眠的新基因SUR1和SUR2。然后从SUR1和SUR的基因表达模式、互作蛋白、上下游基因等方面，对其调节种子休眠分子机制展开研究，并分析SUR1、SUR2 与RDO5调控途径的交叉互作。本研究将加深对种子休眠及RDO5调控途径和网络的认知。

Seed dormancy plays an adaptive role in nature by optimizing germination at the most suitable time. A tight control of dormancy is important in many crop species. Low seed dormancy is required for uniform and fast germination after sowing, and further growth potential; On the other hand, Low levels of dormancy can cause pre-harvest spouting, which can cause economic losses to cereal production including reductions in seed quantity and quality. RDO5 is a newly cloned seed dormancy gene. RDO5 affects seed dormancy without any pleiotropic phenotypes. And RDO5 regulate seed dormancy in an ABA-independent way. Previous research indicates RDO5 may involve in seed stored mRNA regulation and stored protein modification to determine seed germination or not. But the molecular mechanism is still unknown. In order to uncover the mechanism that RDO5 involved, in this project we did EMS mutagenesis screen with rdo5-2, the mutant of RDO5 with very low dormancy. And we got 2 mutants that can rescue dormancy phenotype of rdo5-2, named sur1 (suppressor of RDO5-1) and sur2. We will clone SUR1 and SUR2 through genomic DNA sequencing and SNP linkage analysis. Then we will investigate the detailed mechanism of dormancy regulation by SUR1 and SUR2. We will study their functions, such as gene expression pattern, interaction proteins, and downstream genes on genetics, molecular biology, proteomics and bioinformatics levels and approaches. We also will investigate the crosstalk or difference between RDO5, SUR1, and SUR2. These investigations will further deepen the mechanism of seed dormancy regulation and build up RDO5 seed dormancy regulation pathway or network.