Association between the expression of miR-26 and goat milk fatty acids.

microRNA (miRNA) are small noncoding RNA that regulate protein abundance and are involved in diverse aspects of cellular function including aspects of lipid metabolism in mammary gland of ruminants. Although our previous studies showed that the miR-26 family and its host genes control components of the cellular fatty acid metabolic machinery in goat mammary epithelial cells, a direct relationship between the miR-26 family and milk fatty acids remains unknown. Bioinformatics analysis in this study indicated that the miR-26 family targets belong to the PI3K-Akt signalling pathway, MAPK signalling pathway, and fatty acid biosynthesis pathway. Studies on the relationship of miR-26 family and their host genes with milk composition during mid-lactation revealed that the expression of the miR-26 family and their host genes were associated with total fat yield and short-chain, medium-chain and long-chain fatty acid content, but not lactose or milk protein content. In addition, a significant positive correlation was detected for the expression of the miR-26 family with C16:1 and C18:3 in milk fat. Taken together, our findings demonstrate that the expression of miR-26 is directly related to milk fatty acid composition and underscores the significance of miRNAs in milk fat synthesis regulation.