title: Non-sterol compounds that regulate cholesterogenesis. Analogues of farnesyl pyrophosphate reduce 3-hydroxy-3-methylglutaryl-coenzyme A reductase levels.
abstract: Farnesyl acetate and ethyl farnesyl ether, two analogues of farnesyl pyrophosphate, stimulate post-transcriptional down-regulation of 3-hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) reductase, the rate-limiting enzyme in the biosynthesis of cholesterol and isoprenoids. Farnesyl acetate and ethyl farnesyl ether reduce translation of HMG-CoA reductase mRNA and enhance degradation of the enzyme, the same regulatory effects attributed to the putative non-sterol regulatory metabolite (Goldstein, J.L., and Brown, M.S. (1990) Nature 343, 425-430). HMGal, a fusion protein consisting of the membrane domain of HMG-CoA reductase linked to Escherichia coli beta-galactosidase, is subject to the same regulated degradation as HMG-CoA reductase (Skalnik, D. G., Narita, H., Kent, C., and Simoni, R. D. (1988) J. Biol. Chem. 263, 6836-6841). At 10 micrograms/ml (37.8 microM), farnesyl acetate and ethyl farnesyl ether trigger a 50-80% reduction in HMGal activity. Farnesyl acetate reduces the synthesis of HMG-CoA reductase and HM-Gal by 60-80%, but neither farnesyl compound affects HMG-CoA reductase mRNA levels. Farnesyl acetate and ethyl farnesyl ether stimulated the degradation of HMG-CoA reductase and HMGal, reducing the half-lives of the enzymes by 40-70%. In addition to their regulatory effects on HMG-CoA reductase, these farnesyl compounds also directly disrupt sterol synthesis.
authors.affiliation: Department of Biological Sciences, Stanford University, California 94305-5020.
authors.forename: D L
authors.initials: DL
authors.lastname: Bradfute
authors.forename: R D
authors.initials: RD
authors.lastname: Simoni
mesh_terms: D000818:Animals; D016466:CHO Cells; D002784:Cholesterol / Q000096:biosynthesis*; D006224:Cricetinae; D004926:Escherichia coli / Q000201:enzymology; D006903:Hydroxymethylglutaryl CoA Reductases / Q000096:biosynthesis / Q000378:metabolism*; D007700:Kinetics; D008647:Mesocricetus; D011106:Polyisoprenyl Phosphates / Q000378:metabolism / Q000494:pharmacology*; D014176:Protein Biosynthesis / Q000187:drug effects; D012333:RNA, Messenger / Q000096:biosynthesis; D011993:Recombinant Fusion Proteins / Q000096:biosynthesis; D012717:Sesquiterpenes; D013997:Time Factors; D014162:Transfection; D001616:beta-Galactosidase / Q000096:biosynthesis
chemical_list: D011106:Polyisoprenyl Phosphates; D012333:RNA, Messenger; D011993:Recombinant Fusion Proteins; D012717:Sesquiterpenes; C004808:farnesyl pyrophosphate; D002784:Cholesterol; D006903:Hydroxymethylglutaryl CoA Reductases; D001616:beta-Galactosidase