转录因子SlNur调控番茄果实成熟和营养素代谢的分子机制研究

Fruit not only provides seeds for plant reproduction, but also provides an important source of nutrients for human. Fruit ripening is regulated by key transcription factor networks. It is not only able to acquire a better understanding the molecular mechanism of fruit ripening, but also to understand the regulation of nutrient metabolism during fruit ripening. Our previous study high-throughput screening the members of tomato NAC transcription factor family by VIGS (Virus-induced gene silencing) technology found that SlNur gene silencing significantly affected the maturation process of tomato fruit, but the mechanism regulating fruit ripening and nutrient metabolism is not clear. This project will first obtain the SlNur gene editing and overexpression transgenic tomato, and then use their fruits to do the transcriptome, metabolism and ChIP-seq (Chromatin immunoprecipitation sequencing). On the basis of comprehensive analysis of the above data, the target genes of SlNur gene regulating the ripening and nutrient metabolism in tomato fruit will be excavated and verified by VIGS and EMSA(Electrophoretic mobility shift assay) The results will provide valuable genetic resources for the improvement of fruit ripening and quality through biotechnology breeding in the future.

果实不仅为植物繁衍提供种子，而且是人类重要的营养素来源，成熟是决定种子形成和果实品质的关键过程。果实成熟受关键转录因子网络调控，挖掘新的果实成熟转录因子不仅能完善果实成熟的分子机制，而且能了解果实成熟过程中的营养素代谢调控关系。课题组前期通过病毒诱导基因沉默技术高通量筛选番茄果实NAC转录因子家族成员，发现SlNur基因沉默显著影响了果实的成熟进程，但其调控果实成熟和营养素代谢的机制尚不清楚。本项目将在获得SlNur基因编辑和超表达转基因番茄的基础上，利用转录组、代谢组和ChIP-seq技术系统研究目的基因对番茄果实转录、代谢和靶基因的调控关系，通过EMSA和VIGS验证受SlNur调控的成熟和营养素代谢相关的靶基因，最终明确SlNur通过转录调控参与果实成熟和营养素代谢的分子机制。研究结果将为通过生物技术育种改善果实成熟和品质提供宝贵的基因资源。

果实品质劣变是造成园艺产品采后损失的主要问题，研究果实成熟的转录调控机制是本领域的研究热点。本研究在前期研究基础上，选定NOR-like1为研究对象，通过转基因，转录组和代谢组等技术手段解析其调控果实成熟的机制。本研究通过农杆菌介导的遗传转化获得稳定遗传的SlNOR-like1的基因编辑纯合体材料，以此为材料，开展了转基因材料的转录组，靶基因验证等研究，挖掘了NOR-like1调控乙烯生物合成、果实软化、类胡萝卜素代谢的靶基因，并对其进行了验证，解析了NOR-like1调控果实成熟的分子机制；通过代谢组学分析了野生型和NOR-like1编辑番茄果实的代谢产物变化，初步解析了NOR-like1影响果实营养代谢的机制；在此基础上，我们还发现NOR-like1参与了种子发育，果实失水和和果实大小等调控等重要现象，为后续研究提供了有利线索和研究基础。项目解析SlNOR-like1调控番茄果实成熟和营养代谢的分子机制，丰富果实成熟和营养代谢调控网络。