title: Inactivation of acyl-CoA:cholesterol acyltransferase by ATP+Mg2+ in rat liver microsomes.
abstract: The molecular modulation of acyl-CoA:cholesterol acyltransferase (EC 2.3.2.26) was studied in the microsomes of rat liver. Acyl-CoA: cholesterol acyltransferase was specifically inactivated by ATP and ADP, requiring Mg2+ as a cofactor. The inactivation was not due to substrate diminution nor to inhibition by the activity of acyl-CoA hydrolase, which was not affected by Mg2+ or ATP+Mg2+. Enhancement of inactivation of acyl-CoA: cholesterol acyltransferase by ATP+Mg2+, NaF and a heat-labile cytosolic factor (or factors) is consistent with a protein-kinase catalyzed phosphorylation being involved in the short term regulation of this enzyme.
mesh_terms: D000217:Acyltransferases / Q000037:antagonists & inhibitors*; D000255:Adenosine Triphosphate / Q000494:pharmacology*; D000818:Animals; D000242:Cyclic AMP / Q000494:pharmacology; D006152:Cyclic GMP / Q000494:pharmacology; D003600:Cytosol / Q000201:enzymology; D007700:Kinetics; D008274:Magnesium / Q000494:pharmacology*; D008297:Male; D008862:Microsomes, Liver / Q000201:enzymology*; D051381:Rats; D011919:Rats, Inbred Strains; D012265:Ribonucleotides / Q000494:pharmacology; D012710:Serum Albumin, Bovine / Q000494:pharmacology; D002785:Sterol O-Acyltransferase / Q000037:antagonists & inhibitors*
chemical_list: D012265:Ribonucleotides; D012710:Serum Albumin, Bovine; D000255:Adenosine Triphosphate; D000242:Cyclic AMP; D000217:Acyltransferases; D002785:Sterol O-Acyltransferase; D006152:Cyclic GMP; D008274:Magnesium