Regulation of liver base-exchange activity by acidic phospholipids.
Liver microsomes were enriched in liposomal acidic lipids by Ca(2+)-dependent fusion of liposomes at pH 7.0. The extent of fusion was monitored by the transfer of radioactive cholesteryl oleate. The enrichment of membranes in phosphatidylserine inhibited ethanolamine base-exchange, whereas the fusion with phosphatidylinositol inhibited both ethanolamine and serine base-exchange reactions. In contrast, these two phospholipids had scarce effects on choline base-exchange. Phosphatidic acid did not suppress any of the three base-exchange activities. Possible functional implications are discussed.
Zborowski
J
J
Department of Cellular Biochemistry, Nencki Institute for Experimental Biology, Warsaw, Poland.
Corazzi
L
L
Arienti
G
G
D000818:Animals; D019856:Ethanolamine; D004983:Ethanolamines / Q000037:antagonists & inhibitors / Q000378:metabolism*; D007425:Intracellular Membranes / Q000737:chemistry / Q000378:metabolism; D008081:Liposomes; D008297:Male; D008862:Microsomes, Liver / Q000737:chemistry / Q000378:metabolism*; D010716:Phosphatidylinositols / Q000378:metabolism / Q000494:pharmacology; D010718:Phosphatidylserines / Q000378:metabolism / Q000494:pharmacology; D051381:Rats; D011919:Rats, Inbred Strains; D012694:Serine / Q000037:antagonists & inhibitors / Q000378:metabolism*
D004983:Ethanolamines; D008081:Liposomes; D010716:Phosphatidylinositols; D010718:Phosphatidylserines; D012694:Serine; D019856:Ethanolamine