RRC ID 44623
Author Uyama T, Inoue M, Okamoto Y, Shinohara N, Tai T, Tsuboi K, Inoue T, Tokumura A, Ueda N.
Title Involvement of phospholipase A/acyltransferase-1 in N-acylphosphatidylethanolamine generation.
Journal Biochim. Biophys. Acta
Abstract Anandamide and other bioactive N-acylethanolamines (NAEs) are a class of lipid mediators and are produced from glycerophospholipids via N-acylphosphatidylethanolamines (NAPEs). Although the generation of NAPE by N-acylation of phosphatidylethanolamine is thought to be the rate-limiting step of NAE biosynthesis, the enzyme responsible, N-acyltransferase, remains poorly characterized. Recently, we found that five members of the HRAS-like suppressor (HRASLS) family, which were originally discovered as tumor suppressors, possess phospholipid-metabolizing activities including NAPE-forming N-acyltransferase activity, and proposed to call HRASLS1-5 phospholipase A/acyltransferase (PLA/AT)-1-5, respectively. Among the five members, PLA/AT-1 attracts attention because of its relatively high N-acyltransferase activity and predominant expression in testis, skeletal muscle, brain and heart of human, mouse and rat. Here, we examined the formation of NAPE by PLA/AT-1 in living cells. As analyzed by metabolic labeling with [(14)C]ethanolamine or [(14)C]palmitic acid, the transient expression of human, mouse and rat PLA/AT-1s in COS-7 cells as well as the stable expression of human PLA/AT-1 in HEK293 cells significantly increased the generation of NAPE and NAE. Liquid chromatography-tandem mass spectrometry also exhibited that the stable expression of PLA/AT-1 enhanced endogenous levels of NAPE, N-acylplasmenylethanolamine, NAE and glycerophospho-NAE. Furthermore, the knockdown of endogenous PLA/AT-1 in mouse ATDC5 cells lowered NAPE levels. Interestingly, the dysfunction of peroxisomes, which was caused by PLA/AT-2 and -3, was not observed in the PLA/AT-1-expressing HEK293 cells. Altogether, these results suggest that PLA/AT-1 is at least partly responsible for the generation of NAPE in mammalian cells.
Volume 1831(12)
Pages 1690-701
Published 2013-12
DOI 10.1016/j.bbalip.2013.08.017
PII S1388-1981(13)00188-1
PMID 23994608
MeSH Acylation Animals COS Cells Carbon Radioisotopes Cercopithecus aethiops Ethanolamine / metabolism Ethanolamines / metabolism* Gene Expression Regulation HEK293 Cells Humans Isoenzymes / antagonists & inhibitors Isoenzymes / genetics Isoenzymes / metabolism Membrane Transport Proteins / genetics Membrane Transport Proteins / metabolism* Mice Palmitic Acid / metabolism Peroxisomes / metabolism Phosphatidylethanolamines / biosynthesis* Phospholipases A / antagonists & inhibitors Phospholipases A / genetics Phospholipases A / metabolism* RNA, Small Interfering / genetics RNA, Small Interfering / metabolism Rats Signal Transduction
IF 3.438
Times Cited 12
Human and Animal Cells