叶色是与光合作用、产量直接关联的重要性状。水稻转绿突变体一般表现为苗期失绿，而后逐渐复绿；这类突变体在叶绿体分化与发育等基础研究以及杂交稻制种中的除杂保纯等应用研究中起着重要的作用。通过前期研究，发现渐绿型黄叶突变体grc受一对隐性核基因独立控制，表型上区别于其他叶色突变体的最大特征是植株上生长的每一叶片都必须经历由黄转绿的过程，推断grc为一个新的调控叶绿体早期发育的关键基因，已将其定位在3.7cM内。在已明确grc的形态、生理、细胞、遗传特性及基因初定位区域等的基础上，本项目拟图位克隆水稻黄化转绿基因grc，研究该基因的突变机制、结构特点、时空表达特性、编码蛋白的亚细胞定位及其作用于叶绿素合成途径的可能位点，为深入认识GRC基因的生物学功能及其调控叶片转色的分子机理奠定基础。

Leaf color is an important trait directly related to photosynthesis and grain production. The rice green-revertible mutant generally shows non-green at the early stage and then gradually turns green . This kind of mutant plays an important role both in basic research of chloroplast differentiation and development and in the application research of variety purity in hybrid rice seed producion.From the previous studies we found that grc(green-revertible chlorine) mutant is independent controlled by a pair of recessive nuclear gene.Compared with other leaf mutants in the phenotype,each leaf of grc plant must undergo a process from yellow to green. So we presume that grc could be a new gene regulating the process of chloroplast differentiation and development at the early stage. And it was finally mapped between two SSR markers of 3.7cM.Based on the previous studies of the morphology,physiology,cellular,genetic,gene expression and mapping of grc,this project aims to map-based cloning of grc,clarify its mutation mechanism,analyze its structural features,spatial and temporal expression modules of and the subcellular localization of GRC protein ,and also to identify the possible sites regulated by grc in the chlorophyll synthesis pathway,Which will eventually help us to better understand the biological function of GRC gene and the molecular mechanism of GRC regulating the leaf color.