miR-125b调控奶牛乳腺炎的分子机制

项目名称： miR-125b调控奶牛乳腺炎的分子机制

项目编号： No.31501935

项目类型： 青年科学基金项目

立项/批准年度： 2016

项目学科： 畜牧学与草地科学

项目作者： 罗仍卓么

作者单位： 湖南文理学院

项目金额： 20万元

中文摘要： 前期实验结果表明，与健康奶牛相比，miR-125b在乳腺炎奶牛乳腺组织中的表达量显著降低，靶基因预测结果显示miR-125b可能调控多个免疫基因，该结果提示miR-125b可能在奶牛乳腺炎中有重要调控作用。迄今为止尚未见miR-125b调控奶牛乳腺炎的报道。因此，本项目拟采用双荧光素酶报告基因实验、基因超表达、基因沉默、免疫荧光、qPCR、流式细胞等实验技术，鉴定miR-125b的靶基因；研究miR-125b在奶牛乳腺上皮细胞炎症反应过程中的动态表达模式和分子作用机制；筛查miR-125b前体基因及其靶基因结合位点的SNPs，鉴定SNPs对miR-125b与靶基因结合效率的影响；进行SNPs与奶牛乳腺炎的关联分析，以期筛选与奶牛乳腺炎密切相关的分子标记位点。研究结果将阐明miR-125b在奶牛乳腺炎中的分子调控机制，为解析奶牛乳腺炎的基因网络奠定基础，为乳腺炎抗性分子育种提供新的分子依据。

中文关键词： 牛；乳房炎；microRNA；基因表达调控；分子育种

英文摘要： Previous study in our group revealed that, miR-125b gene expression of the mammary tissues significantly decreased in dairy cattle with mastitis compared with the healthy dairy cattle, and informatics analysis results showed that miR-125b might regulate many genes involved in bovine immunity. The results metioned above suggested that miR-125b might play important roles on bovine mastitis. However, there is no report on the molecular machanism of miR-125b regulating on mastitis in dairy cattle until now. Therefore, in this study, many methods, such as dual luciferase reporter gene assay, gene overexpression, gene silencing, immunofluorescence, qPCR, flow cytometry, will be used to perform the experiments as follows: Firstly, the target genes of bovine miR-125b will be identified. Secondly, the spatio-temportal expression pattern will be detected, and molecular mechanism of miR-125b on mastitis will be clarified during the process of inflammatory response in bovine mammary epithelial cells. Thirdly, SNPs of miR-125b precursor gene and its target genes will be detected, and their effects on binding efficiency between miR-125b and target genes will be identified. Finally, the correlation analysis between SNPs and mastitis will be performed in order to screen the molecular marker loci for mastitis resistance. The results of this project will reveal the function and molecular mechanism of miR-125b on mastitis, which will be the foundations for clarifying the gene network on mastitis, and will provide the new molecular materials for mastitis resistance molecular breeding.

英文关键词： Cattle;Mastitis;microRNA;Gene expression and regulation;Molecular breeding