白菜BrFT2的驯化选择及其调控开花时间的分子机制

开花时间直接影响白菜类作物的产品器官形成和栽培方式，也是环境适应性驯化和育种选择的主要目标性状。挖掘驯化选择过程的关键开花基因，解析抽薹开花的分子机制，是解决白菜类作物先期抽薹等问题的根本途径。本实验室基于白菜核心种质的规模化重测序，鉴定到在不同变种或生态型形成中受到强烈选择的开花时间基因BrFT2；表达谱和序列分析显示，BrFT2基因启动子大片段插入是驯化选择的关键位点，并在开花时间调控中发挥重要作用。本项目拟通过转基因等方法确认BrFT2在调控白菜开花时间中的功能；通过酵母单杂交和染色质免疫共沉淀等鉴定BrFT2上游的转录因子；利用DNA甲基化检测和空间结构互作解析BrFT2启动子在白菜驯化过程中形成的特异转录调控机制。该项研究结果将进一步丰富人们对白菜开花调控的认识，为耐抽薹白菜分子设计育种提供理论依据。

The flowering time directly affects the product organ formation and cultivation mode of Chinese cabbage, and is also the main target character of environmental adaptive domestication and breeding selection. Finding the key flowering gene and analyzing its regulation mechanism is the fundamental way to solve the problems of premature bolting in Chinese cabbage. On the basis of large-scale genome resequencing and selective acclimation analysis of natural population, we found that the flowering regulation genes BrFT2 were strongly selected during the acclimation process of pak choi. Gene expression profile and sequences analysis in different varieties or ecotypes of Chinese cabbage showed that large segment insertion of BrFT2 gene promoter plays an important role in the regulation of flowering time. This project aims to confirm the function of BrFT2 regulating the flowering of Chinese cabbage by transgenic methods; screen the upstream transcription factors by yeast one-hybrid technique and Co-Immunoprecipitation; analyze the transcriptional regulation mechanism of BrFT2 promoter by using DNA methylation detection and chromatin conformation capture. The results of this study will further enrich people's understanding of the regulation of Chinese cabbage flowering, and provide theoretical basis for molecular design and breeding of Chinese cabbage.