Phosphatidylethanolamine derived from phosphatidylserine is deacylated and reacylated in rat hepatocytes.
The metabolism of phosphatidylserine (PS), phosphatidylethanolamine (PE) and phosphatidylcholine (PC), derived from [3H]serine, has been studied in rat hepatocytes. After an initial pulse with radioactivity for 10 min and a chase for up to 240 min, cells were harvested and PS, PE and PC isolated. At the end of the pulse, greater than 90% of [3H]serine derived phospholipid radioactivity was associated with PS. In the subsequent chase, newly-made PS was degraded rapidly with less than 25% of the label lost from PS appearing in the PE and PC pools. In contrast, [3H]serine-labeled PE turnover was not detectable. Very little newly-made PS was converted to PC. PE and PC were further fractionated into molecular species by high-performance liquid chromatography. We report that [3H]serine-labeled PE is deacylated/reacylated with the major product of remodeling being 18:0-20:4 PE. In contrast, [3H]serine-labeled PC is not significantly remodeled.
Samborski
R W
RW
Lipid and Lipoprotein Research Group, University of Alberta, Edmonton, Canada.
Vance
D E
DE
D000215:Acylation; D000818:Animals; D002478:Cells, Cultured / Q000378:metabolism; D008099:Liver / Q000378:metabolism*; D010713:Phosphatidylcholines / Q000378:metabolism; D010714:Phosphatidylethanolamines / Q000378:metabolism*; D010718:Phosphatidylserines / Q000378:metabolism*; D051381:Rats; D012694:Serine / Q000378:metabolism; D014316:Tritium
D010713:Phosphatidylcholines; D010714:Phosphatidylethanolamines; D010718:Phosphatidylserines; D014316:Tritium; D012694:Serine