甘蓝型油菜转录因子BnA.NF-YA7耐旱功能及分子机制研究

项目前期对甘蓝型油菜干旱时的种子发芽率和发芽指数进行全基因组和候选基因关联分析获得了与耐旱性关联的转录因子BnA.NF-YA7。干旱胁迫时，该基因最耐旱的单倍型Hap4材料渗透调节能力最强且BnA.NF-YA7的表达水平上调最快。为进一步研究BnA.NF-YA7的耐旱功能和机制以及不同单倍型材料耐旱性差异的原因，本研究拟：1）分别在中双11中超表达耐旱Hap4和不耐旱Hap3的BnA.NF-YA7，分析两种单倍型转基因T2代植株耐旱性，利用GUS基因比较两者的启动子在干旱时的活性和表达特征；2）定点突变Hap4的BnA.NF-YA7基因耐旱性关联SNP位点，在中双11中超表达后分析T2代植株耐旱性；3）ChIP-Seq和转录组分析鉴定BnA.NF-YA7蛋白的靶基因；4）酵母单杂交筛选Hap4干旱胁迫时BnA.NF-YA7的互作蛋白。本研究结果将对揭示油菜耐旱性分子机制具有重要意义。

In our previous research, we found a drought tolerance associated gene BnA.NF-YA7 in Brassica napus L. based on GWAS and candidate gene association mapping for the germination percentage and germination index under drought stress. The BnA.NF-YA7 expression and osmotic potential under drought stress was higher than other haplotypes(Hap) in the most tolerant haplotype Hap4. To further probe BnA.NF-YA7 mediated drought tolerance function, mechanism and drought tolerant difference among the different haplotypes, we include the following work: 1) Construct BnA.NF-YA7 over-expression vector from drought tolerant Hap4 and drought sensitive Hap3 and transform B.napus Zhongshuang11, compare BnA.NF-YA7 expression and drought tolerance of transgenic plants. Analyze BnA.NF-YA7 promoter activity of drought tolerant Hap4 and drought sensitive Hap3 under drought stress; 2) Point mutation of drought tolerant associated SNP in BnA.NF-YA7 (Hap4→Hap3) and analyze the transgenic rapeseed zhongshuang11 drought tolerance; 3) Identify the BnA.NF-YA7 target gene by ChIP-Seq and transcriptome analysis; 4) Analysis the interaction protein of BnA.NF-YA7(Hap4) during the drought stress using one hybrid yeast test; The research results will provide us the molecular mechanism for drought tolerance in B. napus.