Molecular distinction of phosphatidylcholine synthesis between the CDP-choline pathway and phosphatidylethanolamine methylation pathway. J Biol Chem 1999 Oct 15;274(42):29683-8
Date
10/09/1999Pubmed ID
10514439DOI
10.1074/jbc.274.42.29683Scopus ID
2-s2.0-0033569752 (requires institutional sign-in at Scopus site) 343 CitationsAbstract
In addition to the CDP-choline pathway for phosphatidylcholine (PC) synthesis, the liver has a unique phosphatidylethanolamine (PE) methyltransferase activity for PC synthesis via three methylations of the ethanolamine moiety of PE. Previous studies indicate that the two pathways are functionally different and not interchangeable even though PC is the common product of both pathways. This study was designed to test the hypothesis that these two pathways produce different profiles of PC species. The PC species from these two pathways were labeled with specific stable isotope precursors, D9-choline and D4-ethanolamine, and analyzed by electrospray tandem mass spectrometry. Our studies revealed a profound distinction in PC profiles between the CDP-choline pathway and the PE methylation pathway. PC molecules produced from the CDP-choline pathway were mainly comprised of medium chain, saturated (e.g. 16:0/18:0) species. On the other hand, PC molecules from the PE methylation pathway were much more diverse and were comprised of significantly more long chain, polyunsaturated (e.g. 18:0/20:4) species. PC species from the methylation pathway contained a higher percentage of arachidonate and were more diverse than those from the CDP-choline pathway. This profound distinction of PC profiles may contribute to the different functions of these two pathways in the liver.
Author List
DeLong CJ, Shen YJ, Thomas MJ, Cui ZMESH terms used to index this publication - Major topics in bold
AnimalsCells, Cultured
Cytidine Diphosphate Choline
Liver
Mass Spectrometry
Methylation
Methyltransferases
Phosphatidylcholines
Phosphatidylethanolamine N-Methyltransferase
Phosphatidylethanolamines
Rats
