Stimulation of Ca2+-pump in rat heart sarcolemma by phosphatidylethanolamine N-methylation.
Incubation of purified cardiac sarcolemmal vesicles (SL) in the presence of S-adenosyl-L-methionine, a methyl donor for the enzymatic N-methylation of phosphatidylethanolamine (PE), increased the Ca2+-stimulated ATPase and ATP-dependent Ca2+ accumulation activities. Quantitative analysis of the methylated phospholipids revealed that maximal increase of Ca2+-pump activities was associated with predominant synthesis and intramembranal accumulation of phosphatidyl-N,N-dimethylethanolamine. The stimulation of SL Ca2+-pump activities was prevented by inhibitors of PE N-methylation such as S-adenosyl-L-homocysteine and methyl acetimidate hydrochloride. The results suggest a possible role of PE N-methylation in the regulation of Ca2+-transport across the heart SL membrane.
D000818:Animals; D002118:Calcium / Q000378:metabolism*; D000252:Calcium-Transporting ATPases / Q000378:metabolism*; D007700:Kinetics; D008297:Male; D008745:Methylation; D008780:Methyltransferases / Q000378:metabolism; D009206:Myocardium / Q000201:enzymology*; D050941:Phosphatidyl-N-Methylethanolamine N-Methyltransferase; D010714:Phosphatidylethanolamines / Q000378:metabolism*; D051381:Rats; D011919:Rats, Inbred Strains; D012436:S-Adenosylmethionine / Q000494:pharmacology*; D012508:Sarcolemma / Q000187:drug effects / Q000201:enzymology*
D010714:Phosphatidylethanolamines; C026508:phosphatidyldimethylethanolamine; D012436:S-Adenosylmethionine; D008780:Methyltransferases; D050941:Phosphatidyl-N-Methylethanolamine N-Methyltransferase; D000252:Calcium-Transporting ATPases; D002118:Calcium