PA2 catalyzes the calcium-dependent hydrolysis of the 2-acyl groups in 3-sn-phosphoglycerides. Shows an 11-fold preference for phosphatidylglycerol over phosphatidylcholine (PC). Preferential cleavage: 1-palmitoyl-2-linoleoyl-phosphatidylethanolamine (PE) > 1-palmitoyl-2-linoleoyl-PC > 1-palmitoyl-2-arachidonoyl-PC > 1-palmitoyl-2-arachidonoyl-PE. Plays a role in ciliogenesis.
Expressed in kidney, heart, liver, and skeletal muscle. Also present in placenta and peripheral blood leukocytes. Not detected in brain, colon, thymus, spleen and small intestine. In lung, expressed in bronchial epithelial cells and alveolar macrophages, but scarcely detected in alveolar epithelium, arterial walls and interstitial fibroblasts (at protein level). In joints of osteoarthritis and rheumatoid arthritis, expressed in endothelial cells (at protein level). In normal heart, detected in some vessels. In myocardial tissues with acute infarction, expressed in vascular endothelial cells adjacent to cardiomyocytes and those in lesions with granulation. Expression in cardiomyocytes is scarce (at protein level). In uterus, breast and colon cancers, detected in tumor cells and neighboring microvascular endothelium, but not in normal glandular tissues (at protein level).
Belongs to the phospholipase A2 family.
N-glycosylation does not affect the catalytic activity, but is required for proper secretion. A nonglycosylated form was observed in several cell types. In several cell types, the N- and C-termini are cleaved off.