Converts lysophosphatidic acid (LPA) into phosphatidic acid by incorporating acyl moiety at the 2 position. Has preference for C-18-CoA substrates compared to C-16-CoA substrates. Required for female but not male gametophyte development. a 1-acyl-sn-glycero-3-phosphate + an acyl-CoA = a 1,2-diacyl-sn-glycero-3-phosphate + CoA Phospholipid metabolism; CDP-diacylglycerol biosynthesis; CDP-diacylglycerol from sn-glycerol 3-phosphate: step 2/3. Interacts with GPAT9 and DGAT1. Present in roots, leaves, stems, floral buds and siliques (at protein level). Widely expressed. In contrast to LPAT1, it is not expressed at higher level in leaves. The HXXXXD motif is essential for acyltransferase activity and may constitute the binding site for the phosphate moiety of the glycerol-3-phosphate. Belongs to the 1-acyl-sn-glycerol-3-phosphate acyltransferase family.