转录因子GhNAP调控棉花叶片衰老的网络作用机制研究

Cotton is an important economic crop in China, and its yield has a significant association with China’s crop security. Premature leaf senescence has a negative influence on the yield and quality of cotton, while its key regulation mechanisms still remain unclear. Our previous studies have discovered that down-regulation of GhNAP could delay leaf senescence in cotton and affect cotton yield and its fiber quality, but its further regulation mechanisms are still blank. Thus, through yeast hybrid, ChIP, transgenic technology, realtime quantitative PCR, phenotype analysis, EMSA and so on, we would isolate the interaction protein and the target genes of GhNAP, and its function in order to elucidate its regulation network on leaf senescence. The current research would not only contribute to revealing the molecular mechanisms of leaf senescence in cotton, but also provide the candidate gene in the plant breeding.

棉花是我国重要的经济作物，棉花产量与我国的农作物安全息息相关，然而叶片早衰却严重影响棉花的产量和品质，但棉花叶片衰老调控机制至今仍不太明确。我们已发现在棉花中降低GhNAP的正常表达可以适当延缓叶片衰老，进而对棉花的产量和品质产生影响，因此本研究将在此基础上，系统地探讨转录因子GhNAP调控棉花叶片衰老的网络作用机制。本项目采用酵母杂交、ChIP、转基因、荧光定量PCR、表型分析、EMSA等技术手段，通过分离GhNAP互作蛋白和GhNAP靶基因并解析其功能，试图揭示转录因子GhNAP调控棉花叶片衰老的信号调控网络，这些结果不仅为棉花叶片衰老的分子机制研究提供重要的科学资料，同时也为其他植物的育种提供一个具有潜在育种价值的候选基因。

叶片早衰严重影响棉花的产量和品质，本研究旨在全方位阐明转录因子GhNAP调控棉花叶片衰老的网络作用机制。本研究首次在陆地棉中揭示了转录因子GhNAP所在的NAC家族的不平衡进化和扩增历程；其次在陆地棉中构建了转录因子GhNAP有关的基因共表达网络，发现了一些与转录因子GhNAP有关的共表达基因；随后获得了GhNAP过表达植株以及GhNAP基因敲除植株，与野生型株系相比，GhNAP过表达植株表现出加速叶片衰老的表型，而GhNAP基因敲除植株表现出延迟叶片衰老的表型；同时本研究分离了转录因子GhNAP的靶基因GhPP2C。在项目执行期间，项目负责人以第一作者共发表SCI收录的学术论文4篇。