水稻生育后期早衰基因lps1的分子调控机制及利用

项目名称： 水稻生育后期早衰基因lps1的分子调控机制及利用

项目编号： No.31471473

项目类型： 面上项目

立项/批准年度： 2015

项目学科： 食品科学、农学基础与作物学

项目作者： 邓晓建

作者单位： 四川农业大学

项目金额： 86万元

中文摘要： 水稻生产上早衰现象主要发生在生育后期，它缩短叶片功能期和籽粒灌浆时间，严重影响产量和稻米品质，然而水稻生育后期早衰突变基因克隆迄今鲜有报道。我们通过化学诱变获得一份水稻生育后期早衰突变体lps1，该突变体主要特征为前期生长发育正常，抽穗前后叶片逐渐变黄，灌浆开始后叶片衰老加速，在灌浆中期叶片基本枯死，导致籽粒多为秕粒，遗传分析表明该突变表型由1对隐性核基因控制。前期研究已将该基因精细定位在第10染色体上38.3kb区域内，并通过基因预测和DNA测序确定了一个候选基因，且为新基因。本项目拟构建该基因表达载体，通过转基因互补验证该基因功能，同时，分析该基因时空表达模式和编码蛋白亚细胞定位，系统观察检测该突变体衰老过程中表型特征、生理特性以及相关酶类和活性物质的变化，探讨该基因调控水稻衰老的分子机制，并通过过量表达转基因等途径，探明该基因对延缓水稻衰老、防止早衰、促进高产稳产等方面的应用潜力。

中文关键词： 水稻(Oryza；sativa；L.)；早衰；基因发掘；功能分析；育种利用

英文摘要： Premature senescence occurs mainly in late growth stage of rice production, which shortens leaf function period and grain filling time, seriously affecting the yield and rice quality. However, no late-stage premature senescence gene has been cloned so far in rice. Here we isolated lps1, a late-stage premature senescence mutant of rice, using large-scale mutagenesis. The lps1 mutant exhibited normal growth in early stage. But its leaves gradually turned yellow after heading and accelerated senescence after the start of grain-filling. Most leaves of the lps1 mutant died in the middle of grain-filling, which caused almost all grains to become an abortive grain. Genetic analysis suggested that the phenotype of the lps1 mutant was caused by a recessive mutation in a nuclear gene. In the preliminary study, the lps1 mutant gene had been mapped on 38.3-kb region of rice chromosome 10, and a candidate gene had been identified in this region through DNA sequencing, which revealed that it is a novel gene for premature senescence. In this study, we will construct expression vector of the wild-type LPS1 gene, and confirm its function through genetic complementation test. At the same time, we will further identify its biological function through analysis of spatial and temporal expression patterns of LPS1 gene, subcellular localization of LPS1-GFP fusion protein, investigation of phenotypic and physiological characteristics, and detection of related enzymes and active substances. In addition, we will also evaluate potential application of LPS1 gene in delaying leaf senescence and restraining premature senescence through the overexpression of the wild-type gene.

英文关键词： Rice (Oryza sativa L.);Premature senescence;Genetic identification;Functional characterization;Utilization in breeding