Identification, cloning, expression, and purification of three novel human calcium-independent phospholipase A₂ family members possessing triacylglycerol lipase and acylglycerol transacylase activities

摘要

Isolated novel and purified and characterized phospholipase A₂, referred to herein as calcium-independent phospholipase A₂zeta (iPLA₂zeta) having SEQ. ID. NO: 2 (See FIG. 1), and nucleic acid sequence (SEQ. ID. NO: 4), and calcium-independent phospholipase A₂eta (iPLA₂eta) having SEQ. ID. NO: 3 (See FIG. 1), and nucleic acid sequences (SEQ. ID. NO: 5). For the first time herein, these novel enzymes have been isolated and characterized and are involved in the catalysis, synthesis and hydrolysis of lipids in a living mammalian cell. Moreover, these enzymes iPLA₂zeta and iPLA₂eta through the process of transesterification can catalyze the net anabolic synthesis of triglycerides through a variety of metabolic precursors (e.g. monoacylglycerol, diacylglycerol and acyl CoA).