Chi-miR-3880 mediates the regulatory role of interferon gamma in goat mammary gland

Abstract

A healthy mammary gland is a necessity for milk production of dairy goats. The role of chi-miR-3880 in goat lactation is illustrated in our previous study. Among the differentially expressed genes regulated by chi-miR-3880, one seventh are interferon stimulated genes, including MX1, MX2, IFIT3, IFI44L, and DDX58. As the inflammatory cytokine interferon gamma (IFN{gamma}) has been identified as a potential marker of caseous lymphadenitis in lactating sheep, the interaction between IFN{gamma} and immune-related microRNAs is explored. In this study, it was found that chi-miR-3880 could be one of the microRNAs downregulated by IFN{gamma} in goat mammary epithelial cells (GMECs). The regulation among IFN{gamma}, chi-miR-3880, and DDX58, as well as their roles in mammary gland were investigated. The study illustrated that IFN{gamma}/chi-miR-3880/DDX58 axis modulates GMEC proliferation and lipid formation through PI3K/AKT/mTOR pathway, and regulates apoptosis through Caspase-3 and Bcl-2/Bax. The role of the axis in involution was reflected by the expression of p53 and NF-{kappa}B. In conclusion, IFN{gamma}/chi-miR-3880/DDX58 axis plays an important part in lactation.