May play a general 'housekeeping role' in lipid metabolism. Exhibits both diacylglycerol pyrophosphate (DGPP) phosphatase and phosphatidate (PA) phosphatase activities with no preference for either substrate. May play a role downstream of the ABA signaling pathway during seed germination and in stomatal movement in leaves. PA phosphatase activity not inhibited by N-ethylmaleimide. Expressed in roots, stems, leaves, buds, flowers and siliques. Constitutively expressed. Not induced by stress, mastoparan or hypersensitive response elicitor harpin. Down-regulated by ABA. No visible phenotype under normal growth conditions, but mutant plants show hypersensitivity to ABA and significant PA accumulation during seed germination. Belongs to the PA-phosphatase related phosphoesterase family.