Okadaic acid inhibits phosphatidylethanolamine biosynthesis in rat hepatocytes.
Okadaic acid, a specific inhibitor of protein phosphatase 1 and 2A, inhibited the synthesis of phosphatidylethanolamine via the CDPethanolamine pathway in isolated hepatocytes. Pulse-chase experiments and measurement of the enzyme activity demonstrated that the inhibition of phosphatidylethanolamine synthesis was not caused by an inhibition of CTP:phosphoethanolamine cytidylyltransferase, the putative regulatory enzyme. However, okadaic acid decreased the cellular diacylglycerol level to 30% of that in control cells. The data suggest that the availability of diacylglycerol limits phosphatidylethanolamine synthesis in okadaic acid-treated hepatocytes.
Tijburg
L B
LB
Laboratory of Veterinary Biochemistry, Utrecht University, The Netherlands.
Vermeulen
P S
PS
Schmitz
M G
MG
van Golde
L M
LM
D000818:Animals; D002478:Cells, Cultured; D019856:Ethanolamine; D004983:Ethanolamines / Q000378:metabolism; D004988:Ethers, Cyclic / Q000494:pharmacology*; D007700:Kinetics; D008099:Liver / Q000187:drug effects / Q000378:metabolism*; D008297:Male; D019319:Okadaic Acid; D010714:Phosphatidylethanolamines / Q000096:biosynthesis*; D010743:Phospholipids / Q000096:biosynthesis* / Q000302:isolation & purification; D010749:Phosphoprotein Phosphatases / Q000037:antagonists & inhibitors; D054645:Protein Phosphatase 1; D051381:Rats; D011919:Rats, Inbred Strains
D004983:Ethanolamines; D004988:Ethers, Cyclic; D010714:Phosphatidylethanolamines; D010743:Phospholipids; D019319:Okadaic Acid; D019856:Ethanolamine; D010749:Phosphoprotein Phosphatases; D054645:Protein Phosphatase 1