Phospholipase A2, Group XVI (PLA2G16)

Secretory phopholipase A2 (PLA2) enzymes cleave an acyl ester bond in the sn-2 position of glycerophospholipids. These extracellular proteins have a high disulfide bond content, low molecular mass (14 kDa), and require mM levels of Ca2+ for catalysis. Lipolysis for the provision of fatty acids (FA) for other organs during times of energy demand occurs uniquely in white adipose tissue (WAT). Recent findings have identified a bona fide TAG hydrolase and the major adipose phospholipase A₂, AdPLA. By controlling PGE₂ levels, AdPLA dominantly regulates lipolysis in an autocrine/paracrine manner. Moreover, recent findings demonstrate that, surprisingly, increasing lipolysis in adipose tissue does not necessarily increase serum FA levels, which are usually correlated with insulin resistance.