Altered expression of CCAAT/enhancer binding protein and FABP11 genes during adipogenesisin vitroin Atlantic salmon (Salmo salar)

The study of CCAAT/enhancer binding proteins (C/EBPs) is important in the understanding of adipogenesis, but little is known about their regulation in fish. Here, we report three Atlantic salmon orthologs of c/ebp, and their expression in different tissues and in adipogenesis in vitro. During differentiation the expression of c/ebpα and fatp1 were upregulated in early differentiation stage with continuing high expression level in mature adipocytes, whereas c/ebpδ and fabp11 expression were elevated in mature adipocytes. Furthermore, the fatty acids eicosapentaenoic (EPA) and docosahexaenoic (DHA), suppressed the expression of the c/ebps, pparβ, and fatty acid transport protein (fatp1) during terminal adipocyte differentiation. The study indicates that C/EBPs are induced upon the differentiation of primary-cultured adipocytes from Atlantic salmon and that marine n-3 highly unsaturated fatty acids (HUFAs) affect the c/ebps expressions in mature adipocytes. Therefore, the established cell model described here appears to be valuable for studying modulation of fat content in farmed Atlantic salmon.