Phospholipase A2 Activating Protein (PLAP)

Phospholipase A2-activating protein (PLAP) is potentially important in regulating the inflammatory response through its activation of phospholipase A2, which catalyzes the release of arachidonic acid. By screening a human monocyte cDNA library with a mouse Plap cDNA, Chopra et al. (1999) isolated human PLAP cDNAs. The 738-amino acid human PLAP protein predicted by the cDNA sequence has a molecular mass of 80,826 kD; however, immunoblot analysis using antibodies against PLAP detected a 72- to 74-kD protein in human monocyte cell lysates. In mouse macrophages, an antisense Plap oligonucleotide blocked cholera toxin-induced arachidonic acid release, indicating a role for PLAP in the regulation of phospholipase A2 activation.