Kinetics of lipogenic genes expression in milk purified mammary epithelial cells (MEC) across lactation and their correlation with milk and fat yield in buffalo

• First report of expression of lipogenic genes in milk purified MEC across lactation.
• Genes in de novo milk fat synthesis showed strong correlation with milk yield.
• The study will help to identify the key regulator of milk and fat yield in buffalo.
• Expression of SREBF and PPARγ was high during onset of lactation.

Expression patterns of lipogenic genes (LPL, ABCG2, ACSS2, ACACA, SCD, BDH, LIPIN1, SREBF1, PPARα and PPARγ) were studied in milk purified MEC across different stages of lactation (15, 30, 45, 60, 90, 120 and 240 days relative to parturition) in buffalo. PPARα was the most abundant gene while ABCG2 and ACSS2 had moderate level of expression; whereas expression of SREBF and PPARγ was very low. The expression patterns of some genes (BDH1, ACSS2, and LIPIN1) across lactation were positively correlated with milk yield while negatively correlated with fat yield. SCD also showed weak correlation with milk yield (p, 0.53) and fat yield (p, −0.47). On the other hand, expression pattern of ACACA was negatively correlated with milk yield (p, −0.88) and positively correlated with fat yield (p, 0.62). Strong correlation was observed between genes involved in de novo milk fat synthesis (BDH1, ACSS2, LIPIN2 and SCD) and milk yield.