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Intracellular Platelet-Activating Factor Acetylhydrolase, Type II: A Unique Cellular Phospholipase A2 That Hydrolyzes
1Department of Health Chemistry, Graduate School of Pharmaceutical Sciences, the University of Tokyo, Tokyo, Japan.
Abstract:
Intracellular platelet-activating factor acetylhydrolase, type II [PAF-AH (II)] is a monomeric 40kDa enzyme that was originally purified as an enzyme that hydrolyzes the acetyl group of PAF (1-O-alkyl-2-acetyl-sn-glycero-3-phosphocholine). It can also hydrolyze phospholipids with short length or oxidatively modified sn-2 acyl chains, whereas it can hardly hydrolyze phospholipids with two long fatty acyl chains. PAF-AH (II) is the only phospholipase A2 that is myristoylated at its N-terminus and is evolutionarily conserved from lower organisms to mammals. Studies using cultured cells and mice suggest that PAF-AH (II) functions as an antioxidant phospholipase. Here, we will review our current understanding of PAF-AH (II) and discuss its potential functions in physiological and pathological conditions.
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