%0 Journal Article %A S Yamano %A T Aoyama %A O W McBride %A J P Hardwick %A H V Gelboin %A F J Gonzalez %T Human NADPH-P450 oxidoreductase: complementary DNA cloning, sequence and vaccinia virus-mediated expression and localization of the CYPOR gene to chromosome 7. %D 1989 %J Molecular Pharmacology %P 83-88 %V 36 %N 1 %X The cDNA containing the full coding sequence of human NADPH-P450 oxidoreductase was isolated and completely sequenced. The cDNA contained 2398 base pairs, including 9 and 358 base pairs of 5' and 3' noncoding sequences, respectively. The human NADPH-P450 oxidoreductase protein deduced from the cDNA has 677 amino acids, with a calculated molecular weight of 76,656. The cDNA nucleotide and deduced amino acid sequences displayed 83 and 92% similarities, respectively, with those of the rat NADPH-P450 oxidoreductase. By use of somatic cell hybrids, the NADPH-P450 oxidoreductase gene was regionally localized to human chromosome 7 (7p15-q35). The levels of NADPH-P450 oxidoreductase protein and mRNA were analyzed in 13 human liver specimens and less than 3-fold variation was found among the different livers. The NADPH-P450 oxidoreductase cDNA was inserted into vaccinia virus and expressed in cell culture. The cDNA-expressed enzyme was active in reducing the electron acceptor cytochrome c. In addition, the NADPH-P450 oxidoreductase stimulated the enzymatic activity of vaccinia virus-expressed human P3(450) when both recombinant viruses were used to coinfect human cells in culture. An approximate equal mole level of NADPH-P450 oxidoreductase and P3(450) was required to achieve maximal activity for both ethoxycoumarin O-deethylase and aryl hydrocarbon hydroxylase. %U https://molpharm.aspetjournals.org/content/molpharm/36/1/83.full.pdf