7-Dehydrocholesterol reductase activity is independent of cytochrome P450 reductase

Porter, 2008, Smith-Lemli-Opitz syndrome: pathogenesis, diagnosis and management, Eur. J. Hum. Genet., 16, 535, 10.1038/ejhg.2008.10 Moebius, 1998, Molecular cloning and expression of the human delta7-sterol reductase, Proc. Natl. Acad. Sci. U.S.A., 95, 1899, 10.1073/pnas.95.4.1899 Bae, 1999, Cholesterol biosynthesis from lanosterol. Molecular cloning, tissue distribution, expression, chromosomal localization, and regulation of rat 7-dehydrocholesterol reductase, a Smith-Lemli-Opitz syndrome-related protein, J. Biol. Chem., 274, 14624, 10.1074/jbc.274.21.14624 Nishino, 2000, Evidence for requirement of NADPH-cytochrome P450 oxidoreductase in the microsomal NADPH-sterol Delta7-reductase system, Arch. Biochem. Biophys., 374, 293, 10.1006/abbi.1999.1602 Trzaskos, 1986, Microsomal enzymes of cholesterol biosynthesis. Purification of lanosterol 14 alpha-methyl demethylase cytochrome P-450 from hepatic microsomes, J. Biol. Chem., 261, 14651, 10.1016/S0021-9258(18)66920-0 Li, 2007, Hepatic cytochrome P450 reductase-null mice reveal a second microsomal reductase for squalene monooxygenase, Arch. Biochem. Biophys., 461, 76, 10.1016/j.abb.2007.02.010 Gu, 2003, Liver-specific deletion of the NADPH-cytochrome P450 reductase gene: impact on plasma cholesterol homeostasis and the function and regulation of microsomal cytochrome P450 and heme oxygenase, J. Biol. Chem., 278, 25895, 10.1074/jbc.M303125200 Shefer, 1998, Regulation of rat hepatic 3beta-hydroxysterol delta7-reductase: substrate specificity, competitive and non-competitive inhibition, and phosphorylation/dephosphorylation, J. Lipid Res., 39, 2471, 10.1016/S0022-2275(20)33327-7 Wang, 2005, Relationship between hepatic phenotype and changes in gene expression in cytochrome P450 reductase (POR) null mice, Biochem. J., 388, 857, 10.1042/BJ20042087 Weng, 2005, Hepatic gene expression changes in mouse models with liver-specific deletion or global suppression of the NADPH-cytochrome P450 reductase gene. Mechanistic implications for the regulation of microsomal cytochrome P450 and the fatty liver phenotype, J. Biol. Chem., 280, 31686, 10.1074/jbc.M504447200 Henderson, 2003, Inactivation of the hepatic cytochrome P450 system by conditional deletion of hepatic cytochrome P450 reductase, J. Biol. Chem., 278, 13480, 10.1074/jbc.M212087200 Li, 2009, Chlorzoxazone hydroxylation in microsomes and hepatocytes from cytochrome P450 oxidoreductase-null mice, J. Biochem. Mol. Toxicol., 23, 357, 10.1002/jbt.20299 Porter, 2011, Suppression of cytochrome P450 reductase (POR). Expression in hepatoma cells replicates the hepatic lipidosis observed in hepatic POR-null mice, Drug Metab. Dispos., 39, 966, 10.1124/dmd.111.038562 Lange, 2008, Effectors of rapid homeostatic responses of endoplasmic reticulum cholesterol and 3-hydroxy-3-methylglutaryl-CoA reductase, J. Biol. Chem., 283, 1445, 10.1074/jbc.M706967200 Song, 2005, Insig-mediated degradation of HMG CoA reductase stimulated by lanosterol, an intermediate in the synthesis of cholesterol, Cell Metab., 1, 179, 10.1016/j.cmet.2005.01.001 Gill, 2011, Cholesterol-dependent degradation of squalene monooxygenase, a control point in cholesterol synthesis beyond HMG-CoA reductase, Cell Metab., 13, 260, 10.1016/j.cmet.2011.01.015