mRNA expression of genes related to fat deposition during in vitro ovine adipogenesis

Fat deposition in animals involves adipogenic differentiation guided by transcriptional factors and other key factors. To understand the molecular mechanism underlying ovine adipogenic differentiation, the dynamic mRNA expression of key genes related to fat deposition, including peroxisome proliferator-activated receptor-γ (PPAR-γ), fatty acid-binding protein 4 (FABP4), FABP5, and cellular retinoic acid-binding protein 2 (CRABP2), were analyzed during in vitro differentiation of ovine preadipocytes. The stromal vascular cells from underneath the tail fat tissue of 1-wk-old sheep were isolated and cultured, and the preadipocytes were induced using a cocktail of 3-isobutyl-1-methylxanthine, insulin, dexamethasone, and troglitazone. The cultivated cells were collected at different time points after induced differentiation. The expression levels of PPAR-γ, FABP4, FABP5, and CRABP2 were studied by quantitative real-time polymerase chain reaction. The expressions of these genes in sheep were compared with those in human and mouse retrieved from the Gene Expression Omnibus DataSets. We observed that the expression of PPAR-γ, FABP4, and FABP5 was increased upon differentiation of ovine preadipocytes, as in humans and mice. The expression of CRABP2 was sharply increased from days 0 to 2 after induced differentiation and was subsequently decreased. This expression pattern of CRABP2 was different from that observed in humans and mice. Our results provide new insights into the function of these genes in fat deposition.