在两系杂交稻育种实践中，发现了籼稻两用核不育系突变株812HS，表现在分蘖中后期，叶绿素受强烈阳光辐射，引起光氧化伤害而导致叶片失绿，光合能力下降。该性状不同于淡黄叶突变体性状，部分遮光后并不表现光氧化表型。光合生理研究表明，光合效率各项参数明显降低。遗传分析表明，该性状受控于一个新的水稻光氧化相关显性基因LPO1。已将基因定位在第4染色体上约55.42 kb范围内，并预测了1个与叶片失绿性状密切相关的候选基因。本申请拟用转基因、基因沉默和敲除的方法验证LPO1基因，并进行蛋白体外表达、互作分析、亚细胞定位和时空表达模式研究，再从叶绿体结构特性、光合性能、活性氧清除能力、光反应中心对光能利用能力的改变等方面明确LPO1的生理功能。本研究对于阐明水稻光氧化的分子遗传机理和缓解水稻光氧化的研究具有重要意义。

A mutant of two-line sterile rice 812HS, is found having leaf photo-oxidation during tillering-jointing stage since its chloroplast is easy harmed by strong sunlight. The trait has been found to be controlled by a new dominant gene, LPO1 (leaf photo-oxidation 1) by its classical genetic analysis. Using a F2 population, LPO1 has been mapped on a segment on Chromosome 4 within 55.42 kb，and forecasted a target gene by bioinformatics analysis. The present proposal plans to clone the base sequences of LPO1. By transformation, inhibition and knock-out LPO1 gene, the present proposal will validate the trait of photo-oxidation of LPO1, and research its molecular mechanism and physiological function. The research would enrich the theory of rice leaf photo-oxidation at molecular base, and offer a support at theory and gene resource to non-photo-oxidation rice study and breeding.