DGAT (acyl-CoA: diacylglycerol acyltransferase) is a transmembrane enzyme that acts in the final and committed step of triacylglycerides (TAGs) synthesis, and it has been proposed to be the rate-limiting enzyme in plant storage lipid accumulation. DGAT catalyzes the acylation of sn-1,2-diacylglycerol (DAG) at the sn-3 position using an acyl-CoA substrate. DGAT has been proposed to be the rate-limiting enzyme in plant storage lipid accumulation. DGAT is considered a key enzyme for biotechnological purposes; it might be utilized to increase oil content in oleaginous plant species.

DGAT1 and DGAT2 are two of the enzymes that are responsible for the main part of TAG synthesis in most organisms, and they have been studied in many eukaryotic organisms.