Plasmalogen-selective phospholipase A2 and its role in signal transduction

The breakdown of plasmalogens in neural membranes is a receptor-mediated process catalyzed by a plasmalogen-selective phospholipase A2. This enzyme has been isolated from bovine brain. It is localized in cytosol and does not require Ca2+ for its activity. It has a molecular weight of 39 kDa and is strongly inhibited by glycosaminoglycans, gangliosides and sialoglycoproteins. The interactions between plasmalogen-selective phospholipase A2 and glycoconjugates may be involved in the regulation of enzymic activity. Under normal conditions, plasmalogen-selective phospholipase A2 provides second messengers such as arachidonic acid and eicosanoids. However, under pathological conditions, this enzyme may be involved in a massive release of free fatty acids that may cause serious cell and tissue damage.