Rubisco活化酶（RCA）是植物光合作用过程中的关键酶，具有调节Rubisco活性的功能。已有大量研究表明RCA基因对于植物的光合效率、产量形成和逆境响应具有重要作用。然而，人们对调控RCA基因表达的分子遗传机制还知之甚少。本项目前期克隆了棉花的两个RCA基因并分析了其组织表达规律，结果发现GhRCAα和GhRCAβ在叶片中表达量最高但具有不同的表达模式。相比GhRCAα，GhRCAβ在mRNA水平和蛋白水平具有较高的表达。本项目在此基础上利用一套棉花重组自交系群体（RIL）全基因组鉴定调控RCA基因表达的eQTL，并定位产量QTL，进一步分析两个RCA基因与产量之间的关系；同时，在自然群体中鉴定关键eQTL区段的优异等位变异和最优单倍型，开发与棉花RCA基因表达水平相关的分子标记或功能标记。研究结果可为育种上通过分子标记手段调控RCA基因表达，实现棉花光合能力和产量的提高提供新思路。

Rubisco activase, one of the key photosynthetic enzyme, that regulate the activity of Rubisco in plant. Numerous studies have indicated that endogenous levels of RCA could serve as an important determinant of photosynthetic efficiency, plant productivity and stress response. However, the molecular mechanism of transcriptional regulation about RCA genes has thus far remained unknown. In the previous work of this project, we have cloned GhRCAα and GhRCAβ, and analyzed the tissue expression of two RCA genes. It was found that GhRCAα and GhRCAβ in cotton were highly expressed in leaves, but that their expression pattern were significantly different. Compared with GhRCAα, GhRCAβ was expressed at higher mRNA and protein levels. On this basis, this study will detect expression quantitative trait loci (eQTL) for RCA genes and quantitative trait loci (QTL) for yield related traits using recombinant inbred lines population and further investigate the relationship between the effect of RCA genes expression on cotton photosynthesis and productivity. Simultaneously, through the association analysis on the key eQTL interval in natural population, we will detect the excellent allelic variation and optimal haplotype, and develop functional markers closely linked with RCA genes expression. These results could provide a new train of thought for increasing overall cotton photosynthesis and productivity by regulating expression of RCA genes through marker-assisted breeding.