Regulation of hepatic dolichol synthesis by beta-hydroxy-beta-methylglutaryl coenzyme A reductase.

Regulation of hepatic 3-hydroxy-3-methylglutaryl coenzyme A reductase and cholesterol synthesis.

Rat liver microsomal 3-hydroxy-3-methylglutaric acid (HMG)-coenzyme A reductase (mevalonate:NADP oxidoreductase (acylating CoA), EC 1.1.1.34) exhibits a cyclic rhythm with peak activity at midnight. HMG-CoA reductase from microsomes of rats killed at noon and midnight has similar properties. Cycloheximide completely prevents the 5to IO-fold rise in activity which occurs from 6 p.m. to midnight,...

Stimulation of 3-hydroxy-3-methylglutaryl-coenzyme A reductase in mouse uterine epithelial cells by oestradiol-17 beta.

The characteristics of 3-hydroxy-3-methylglutaryl-CoA reductase from mouse uterine epithelial cells were studied. Preliminary experiments showed that enzyme activity was stimulated approx. 10-fold 18h after administration of 100ng of oestradiol-17 beta. This activity was associated with all particulate fractions of the uterine luminal cell. The Km for D-3-hydroxy-3-methylglutaryl-CoA was 5.54 +...

Regulation of 3-hydroxy-3-methylglutaryl coenzyme A reductase by reversible phosphorylation-dephosphorylation.

Regulation of 3-hydroxy-3-methylglutaryl coenzyme A reductase activity and cholesterol biosynthesis by oxylanosterols.

Treatment of rat intestinal epithelial cell cultures with the oxidosqualene cyclase inhibitor, 3 beta-[2-(diethylamino)-ethoxy]androst-5-en-17-one (U18666A), resulted in an accumulation of squalene 2,3:22,23-dioxide (SDO). When U18666A was withdrawn and the cells were treated with the sterol 14 alpha-demethylase inhibitor, ketoconazole, SDO was metabolized to a product identified as 24(S),25-ep...

3-Hydroxy-3-methylglutaryl coenzyme A reductase: regulation of enzymatic activity by phosphorylation and dephosphorylation.

The activity of microsomal 3-hydroxy-3-methylglutaryl coenzyme A reductase (HMG-CoA reductase) [mevalonate:NADP+ oxidoreductase (CoA-acylating); EC 1.1.1.34] was inhibited by ATP+Mg2+. Inactivation of HMG-CoA reductase by ATP+Mg2+ was dependent on time, temperature, and ATP concentration. Incubation of microsomal HMG-CoA reductase with [gamma-32P]ATP+Mg2+ was associated with a reciprocal increa...