RRC ID 56116
Author Hussain Z, Uyama T, Kawai K, Binte Mustafiz SS, Tsuboi K, Araki N, Ueda N.
Title Phosphatidylserine-stimulated production of N-acyl-phosphatidylethanolamines by Ca2+-dependent N-acyltransferase.
Journal Biochim Biophys Acta Mol Cell Biol Lipids
Abstract N-acyl-phosphatidylethanolamine (NAPE) is known to be a precursor for various bioactive N-acylethanolamines including the endocannabinoid anandamide. NAPE is produced in mammals through the transfer of an acyl chain from certain glycerophospholipids to phosphatidylethanolamine (PE) by Ca2+-dependent or -independent N-acyltransferases. The ε isoform of mouse cytosolic phospholipase A2 (cPLA2ε) was recently identified as a Ca2+-dependent N-acyltransferase (Ca-NAT). In the present study, we first showed that two isoforms of human cPLA2ε function as Ca-NAT. We next purified both mouse recombinant cPLA2ε and its two human orthologues to examine their catalytic properties. The enzyme absolutely required Ca2+ for its activity and the activity was enhanced by phosphatidylserine (PS). PS enhanced the activity 25-fold in the presence of 1 mM CaCl2 and lowered the EC50 value of Ca2+ >8-fold. Using a PS probe, we showed that cPLA2ε largely co-localizes with PS in plasma membrane and organelles involved in the endocytic pathway, further supporting the interaction of cPLA2ε with PS in living cells. Finally, we found that the Ca2+-ionophore ionomycin increased [14C]NAPE levels >10-fold in [14C]ethanolamine-labeled cPLA2ε-expressing cells while phospholipase A/acyltransferase-1, acting as a Ca2+-independent N-acyltransferase, was insensitive to ionomycin for full activity. In conclusion, PS potently stimulated the Ca2+-dependent activity and human cPLA2ε isoforms also functioned as Ca-NAT.
Volume 1863(5)
Pages 493-502
Published 2018-5-1
DOI 10.1016/j.bbalip.2018.02.002
PII S1388-1981(18)30022-2
PMID 29447909
MeSH Acyltransferases / chemistry Acyltransferases / metabolism* Amino Acid Sequence Animals Biosynthetic Pathways / drug effects COS Cells Calcium / pharmacology* Cations, Divalent / pharmacology Cell Survival / drug effects Chlorocebus aethiops Ethanolamines / metabolism Humans Ionomycin / pharmacology Mice Phosphatidylethanolamines / metabolism* Phosphatidylserines / metabolism* Phospholipases A2, Cytosolic / chemistry Phospholipases A2, Cytosolic / metabolism Plasmalogens / metabolism RAW 264.7 Cells Sequence Homology, Amino Acid
IF 4.402
Times Cited 5
Human and Animal Cells RAW 264(RCB0535)