产量性状改良是甘蓝型油菜育种的重要目标之一，关于miRNA调控油菜产量性状的研究还未见报道。本项目基于不同角果性状甘蓝型油菜的sRNA-Seq和RNA-Seq筛选到大量差异表达miRNA和基因，其中miR393在角果长度、密度增加的材料中下调表达，其靶基因TIR1/AFB2上调表达，推测miR393及其靶基因可能与角果性状相关。本研究拟通过miR393及靶基因的功能验证，结合转基因材料的表型观察、生长素含量测定及相关信号路径的基因表达分析，了解miR393及靶基因对甘蓝型油菜花、角果和种子大小的影响。通过靶基因转基因材料的ChIP-Seq和RNA-Seq筛选TIR1/AFB2调控的下游基因，并通过ChIP-qPCR和EMSA验证其调控和结合下游基因的靶位点；结合酵母双杂交筛选、BiFC和Co-IP验证TIR1/AFB2的互作蛋白，解析miR393及靶基因对甘蓝型油菜生殖器官大小的调控机制。

Yield trait improvement is one of the important objectives in Brassica napus breeding. However, researches on miRNA regulating yield traits have never been reported in rapeseed. Previously, we screened a number of differentially expressed miRNAs and genes between rapeseeds with different silique traits, using sRNA-Seq and RNA-Seq. We found miR393 was down-regulated in B. napus with longer silique and higher silique density, and its target genes (TIR1, AFB2) were up-regulated, indicating miR393 and the target genes might be related to variation in silique traits. In this research, we will perform functional verification of miR393 and the target genes. Supporting with the phenotypic data and auxin content of transgenic plants, as well as expressional pattern of genes involved in auxin-related signal pathways, we will acknowledge the effects of miR393 and the target genes on regulating size of rapeseed floral organ, silique and seeds. The downstream genes regulated by TIR1 and AFB2 will be screened using ChIP-Seq and RNA-Seq, and the target sites regulated or bound by TIR1 and AFB2 will be confirmed using ChIP-qPCR and EMSA. The interaction proteins of TIR1 and AFB2 will be screened using yeast two-hybrid system, and then confirmed with BiFC and Co-IP analysis. This work will decipher the mechanism of miR393 and its target genes in regulating size of reproductive organs in rapeseed.