甜瓜果实成熟相关转录因子CmNAC-NOR下游调控机制解析

Fruit ripening process is a key factor to affect fruit quality and shelf life. Melon (Cucumis melo L.) has emerged as an interesting model for fruit ripening studies due to the existence of both climacteric and non-climacteric genotypes within the species. The research on melon fruit ripening related genes has been tentatively explored. However, the discovery of key genes in fruit ripening and their regulatory pathways are still poorly understood. CmNAC-NOR encodes one of NAC family transcription factors, which involved in the onset of fruit climacteric, but the molecular mechanism of CmNAC-NOR in regulating fruit ripening remains elusive. In this project, we will generate CmNAC-NOR knock out and ectopic expression transgenic plants, look for the downstream function genes of CmNAC-NOR and investigate the regulating network of CmNAC-NOR. The results would enrich the theoretical knowledge of fruit ripening, and provide theoretical and technology basis for the improvement of melon breeding and postharvest storage.

果实成熟进程是影响果实品质和采后货架期的关键因素。甜瓜(Cucumis melo L.)同时具有呼吸跃变型和非呼吸跃变型两种果实成熟类型，是研究肉质果实成熟机理的理想材料。目前，甜瓜果实成熟相关基因的研究虽有初步探索，但关键基因的发掘及其调控途径还知之甚少。CmNAC-NOR基因编码一个NAC家族转录因子，参与调控甜瓜果实的呼吸跃变，但其下游调控机理尚不清楚。本项目在获得CmNAC-NOR基因敲除和基因特异表达的甜瓜转基因植株的基础上，进一步挖掘CmNAC-NOR下游果实成熟相关的功能基因，解析CmNAC-NOR对甜瓜果实呼吸跃变的下游调控途径和分子作用机制。研究成果可丰富果实成熟发育的理论知识，有望为甜瓜品种改良和采后储运等提供理论和技术参考。

果实成熟进程是影响果实品质和采后货架期的关键因素。甜瓜(Cucumis melo L.)同时具有呼吸跃变型和非呼吸跃变型两种果实成熟类型，是研究肉质果实成熟机理的理想材料。本课题建立了一套稳定的甜瓜遗传转化体系，成功编辑了甜瓜果实的呼吸跃变调控基因CmNAC-NOR，获得了该基因不同程度的敲除突变体。在此基础上，通过DAP-SEQ，EMSA等技术成功解析了CmNAC-NOR基因的下游调控途径，发现CmNAC-NOR基因可同时调控影响果实成熟的若干重要基因，其中包括乙烯合成基因，叶绿素降解基因，类胡萝卜素合成基因、赤霉素降解基因等。该研究成果可丰富果实成熟发育的理论知识，有望为甜瓜品种改良和采后储运等提供理论和技术参考。