GPAT2 is an 801 amino acid mitochondrial multi-pass membrane protein belonging to the GPAT/DAPAT family. GPAT2 is highly expressed in testis with lower levels in heart, liver, kidney, spleen and adipose cells. Inhibited by N-ethylmaleimide (NEM), GPAT2 esterifies an acyl-group from acyl-ACP to the sn-1 position of glycerol-3-phosphate, an essential step in glycerolipid biosynthesis. GPAT2 contain a HXXXXD motif, which is critical for acyltransferase activity and may constitute the binding site for the phosphate moiety of the glycerol-3-phosphate. Three isoforms of GPAT2 exist due to alternative splicing events.