Phosphorylation and Modulation of Enzymic Activity of 3-Hydroxy-3-Methylglutaryl Coenzyme A Reductase by Multiple Kinases
3-Hydroxy-3-methylglutaryl coenzyme A reductase (HMG-CoA reductase, EC 188.8.131.52) is the rate-limiting enzyme which regulates the synthesis of cholesterol and other polyisoprenoid compounds (Rodwellet al., 1976; Goldstein and Brown, 1977; Brown and Goldstein, 1980; Ingebritsen and Gibson, 1980; Beg and Brewer, 1981, 1982; Kennelly and Rodwell, 1985; Beget al., 1987). In mammalian cells, HMG-CoA reductase is a transmembrane glycoprotein with its active site facing the cytosol and a carbohydrate-containing site oriented toward the luminal surface of the endoplasmic reticulum. The protomer of HMG-CoA reductase is an approximately 100,000-D protein (Chinet al., 1984). Proteolysis (Nesset al., 1981) of the native protein results in a 53,000 molecular weight fragment that contains the active site of the enzyme (Chinet al., 1984).
KeywordsMevalonic Acid Molecular Weight Fragment Kinase System Phosphoprotein Phosphatase Methylglutaryl Coenzyme
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