Molecular Regulation of Yak Preadipocyte Differentiation and Proliferation by and ceRNA Regulatory Network Analysis.

The positive regulatory role of in differentiation and lipid deposition in yak intramuscular preadipocytes has been demonstrated in our previous study. However, the regulatory mechanisms remain unclear. In this study, we aimed to produce complete mRNA and microRNA (miRNA) profiles after adenovirus-mediated overexpression in yak preadipocytes using high-throughput sequencing. We constructed a competing endogenous RNA (ceRNA) network with as the core and identified the functions of the selected target miRNA during cell proliferation and differentiation. We obtained 118 differentially expressed genes (DEGs) after overexpression, 76 of which were up-regulated, including Notch signaling members , , and , and 42 DEGs were down-regulated, including genes related to the cell cycle (, , , , and ). Additionally, many ubiquitin-mediated proteolysis pathway members were also significantly up-regulated (, , , and ). MiRNA sequencing showed that 13 miRNAs were significantly up-regulated, and 12 miRNAs were down-regulated. Among them, 29 targets of 10 differentially expressed miRNAs (DEMs) were differentially expressed, including miR-152-, miR-6529a-, miR-148c-, and the miR-6529b- axis. We further verified that overexpression and inhibition of miR-6529a can inhibit and promote, respectively, the proliferation and differentiation of preadipocytes. Taken together, our study not only revealed the regulatory network of during yak preadipocytes differentiation but also laid a foundation for elucidating the cause for lower intramuscular fat content in yaks at the molecular level.