应用高通量测序技术检测与奶牛乳产量和乳质量调控相关的miRNA

本实验将中国荷斯坦牛泌乳期高乳品质奶牛（H）和泌乳期低乳品质奶牛（L）乳腺组织作为实验对象，利用高通量测序技术进行了miRNA测序，与miRNA数据库比对，获得已知miRNA，整合miREvo和mirDeep2这两个miRNA预测软件，进行新miRNA分析，通过差异表达分析筛选组间差异miRNAs，获得56个差异表达miRNA(P <0.05，FDRq <0.05)并对差异表达miRNA进行靶基因预测；利用DAVID对靶基因进行GO(Gene Ontology)和信号通路富集分析。经过对靶基因筛选，发现了4个已报道与乳蛋白、乳脂紧密相关的功能基因：CSN3、SCD、LALBA和DGAT2。靶基因聚集的生物学功能多数参与了蛋白质和脂肪代谢，乳腺发育和分化，以及免疫功能。靶基因主要富集在MAPK 信号通路、甘油磷酸脂质代谢、缺氧诱导因子1和磷脂酰肌醇3激酶 蛋白激酶B信号转导通路。结果显示，靶基因主要富集在糖类代谢、脂肪代谢、蛋白质代谢、细胞凋亡以及免疫相关通路。

Application of High Throughput Sequencing Technology in Dairy Cow Milk Production and Milk Quality Control miRNA

To investigate the microRNA(miRNA) expression profiles in cow mammary glands of cows with varying milk quality, high throughput sequencing technology was used to detect the expression of miRNAs in high milk quality cows mammary glands(H) and low milk quality cows mammary glands(L). Using miRNA database tools, miREvo, and mirDeep2 software analysis, 56 differentially expressed miRNAs were identified(P < 0.05, FDRq<0.05). GO(Ontology Gene) and signal pathway enrichment analysis of target genes were conducted with DAVID. Screening of the target genes indicated that four genes(CSN3, SCD, LALBA and DGAT2) have been previously reported to be associated with the synthesis of milk protein and milk fat. Other target genes were found to be involved in glucose metabolism, protein and lipid metabolism, cell development and differentiation, and immune functions(P<0.01, false discovery rate(FDR) q<0.01). Target genes were mainly enriched in mitogen activated protein kinases(MAPK), glycerol phospholipid metabolism, hypoxiainducible factor-1(HIF-1), and the PI3K-Akt signaling pathway. The predicted target genes of the miRNAs were mainly enriched in carbohydrate metabolism, fat metabolism, protein metabolism, cell apoptosis and immune related pathways.