The output of triglyceride and cholesterol, and the activity of microsomal 3-hydroxy-3-methylglutaryl coenzyme A reductase (HMG-CoA reductase) were measured following perfusion of the isolated rat liver with a medium containing free fatty acids. The activity of the enzyme and the output of cholesterol and triglyceride are regulated by the quantity and structure of the free fatty acid. The activ...

Insig-1 and Insig-2 are closely related proteins of the endoplasmic reticulum (ER) that mediate feedback control of cholesterol synthesis by sterol-dependent binding to the following two membrane proteins: the escort protein Scap, thus preventing proteolytic processing of sterol regulatory element-binding proteins; and the cholesterol biosynthetic enzyme 3-hydroxy-3-methylglutaryl CoA reductase...

Comprising a major clade of Anura, toads produce and secrete numerous toxins from both the parotoid glands behind their eyes dorsal skin. These toxins, made various proteins compounds, possess pharmacological potential to be repurposed benefit human health. However, detailed genetic regulation toad toxin production is still poorly understood. A recent publication uncovering genome representativ...

CR39 is a cholesterol-repressible rat liver cDNA previously isolated by differential hybridization (Clarke, C.F., Tanaka, R.D., Svenson, K., Wamsley, M., Fogelman, A.M., and Edwards, P.A. (1987) Mol. Cell. Biol. 7, 3138-3146). To precisely identify the function of CR39 a fusion protein was constructed that contained the amino-terminal region of the bacterial protein anthranilate synthetase fuse...

Rat liver microsomal 3-hydroxy-3-methylglutaryl-CoA reductase [HMG-CoA reductase; mevalonate:NADP+ oxidoreductase (CoA-acylating), EC 1.1.1.34], the key regulatory enzyme in cholesterol biosynthesis, has been purified to apparent homogeneity. Purified HMG-CoA reductase yields a single diffuse band when NaDodSO4/polyacrylamide gels are stained with Coomassie blue and yields two adjacent bands wh...

Sitosterolemia is a recessively inherited disorder characterized by abnormally increased plasma and tissue plant sterol concentrations. Patients have markedly reduced whole body cholesterol biosynthesis associated with suppressed hepatic, ileal, and mononuclear leukocyte 3-hydroxy3-methylglutaryl coenzyme A (HMG-CoA) reductase, the ratecontrolling enzyme in cholesterol biosynthetic pathway, cou...

Pannorin, a naphthopyrone that inhibits 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase, the rate-limiting enzyme in cholesterol synthesis, was isolated from a culture broth of Chrysosporium pannorum M10539 by solvent extraction, Bio-Gel P-6 column chromatography and reverse phase HPLC (Silica ODS). Spectroscopic analyses of the compound yielded 4,8,10-trihydroxy-5-methyl-2H-naphtho[1...

Because the small bowel is a site of significant cholesterol synthesis, we determined the ileal distribution of 3-hydroxy-3-methylglutaryl-coenzyme A reductase (HMG-CoA reductase), the rate-limiting enzyme of the cholesterol biosynthetic pathway. Immunofluorescence microscopy on unfixed snap-frozen sections of ileum and jejunum from untreated rats or dogs showed HMG-CoA reductase in the absorpt...

Parabiont rats were used to study the regulation of intestinal cholesterol synthesis (3-hydroxy-3-methylglutaryl coenzyme A [HMG-CoA] reductase activity) and esterification (acylcoenzyme A/cholesterol acyltransferase [ACAT] activity) by lipoproteins and micellar cholesterol. The parabiont rat model offers a unique way to observe changes in cholesterol metabolism in the intestine, independently ...

OBJECTIVE Integrin-mediated cell adhesion to type I fibrillar collagen regulates gene and protein expression, whereas little is known of its effect on lipid metabolism. In the present study, we examined the effect of type I fibrillar collagen on cholesterol biosynthesis in human aortic smooth muscle cells (SMCs). METHODS AND RESULTS SMCs were cultured on either fibrillar or monomer collagen f...