Reversible inactivation-reactivation of 3-hydroxy-3-methylglutaryl coenzyme A reductase of rat intestine.
3-Hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase in the ileum of rats was inactivated by Mg2+-ATP and reversibly reactivated by cytoplasmic activator from the liver. The mevalonate kinase reaction was presumably not involved in this inactivation. Studies of nucleotide specificity for the inactivation revealed that ATP was most effective in the reaction among the nucleotides tested. In contrast to the hepatic microsomal HMG-CoA reductase, more than one-half of intestinal reductase existed in an active form. These observations indicated the presence of phosphorylation-dephosphorylation mechanism for modulation of intestinal HMG-CoA reductase.
D000255:Adenosine Triphosphate / Q000494:pharmacology; D000818:Animals; D004789:Enzyme Activation; D006903:Hydroxymethylglutaryl CoA Reductases / Q000378:metabolism*; D019161:Hydroxymethylglutaryl-CoA Reductase Inhibitors; D007082:Ileum / Q000201:enzymology*; D007700:Kinetics; D008297:Male; D051381:Rats; D011919:Rats, Inbred Strains; D012265:Ribonucleotides / Q000494:pharmacology; D012969:Sodium Fluoride / Q000494:pharmacology
D019161:Hydroxymethylglutaryl-CoA Reductase Inhibitors; D012265:Ribonucleotides; D000255:Adenosine Triphosphate; D012969:Sodium Fluoride; D006903:Hydroxymethylglutaryl CoA Reductases