Abstract
N -Acylethanolamines (NAEs) are a class of lipid mediators and widely present in various organisms including animals and plants. NAEs are ethanolamides of long-chain fatty acids and exhibit a variety of biological activities such as anti-inflammation, analgesia, and appetite suppression. NAEs are produced from membrane glycerophospholipids and act as the trigger of signal transduction and gene expression through receptors. Studies over the past three decades have identified a series of enzymes involved in the generation and degradation of NAEs and clarified the complexity of their metabolic pathways. N -Acyltransferase initiates the biosynthesis of NAEs and is regarded as the rate-limiting enzyme regulating the levels of NAEs. The enzyme produces the precursor of NAEs, N -acylphosphatidylethanolamine, by transferring an acyl chain of glycerophospholipids to the amino group of phosphatidylethanolamine. Two types of N -acyltransferases have been identified: Ca2+-dependent cytosolic phospholipase A2ε (cPLA2ε) and Ca2+-independent phospholipase A and acyltransferase (PLAAT) family members. These N -acyltransferases differ in primary structures, enzymatic properties, and tissue distributions, and thus have been thought to function in distinct occasions. In this minireview, we overview recent advances in the field of NAE research, focusing on the physiological and pathophysiological functions of cPLA2ε and PLAAT family revealed by the analysis of knockout mice of these enzymes.
