NADH-cytochrome b5 reductase 3 is an enzyme that in humans is encoded by the CYB5R3gene.
Two forms of NADH-cytochrome b5 reductase are known, a membrane-bound form in somatic cells (anchored in the endoplasmic reticulum, mitochondrial and other membranes) and a soluble form in erythrocytes. The former exists mainly on the cytoplasmic side of the endoplasmic reticulum and functions in desaturation and elongation of fatty acids, in cholesterol biosynthesis, and in drug metabolism. The erythrocyte form is located in a soluble fraction of circulating erythrocytes and is involved in methemoglobin reduction. The membrane-bound form has both membrane-binding and catalytic domains. The soluble form has only the catalytic domain. This gene encodes both forms of the enzyme which arise from tissue-specific alternative transcripts that differ in the first exon. Mutations in this gene cause methemoglobinemias.
^Tomatsu S, Kobayashi Y, Fukumaki Y, Yubisui T, Orii T, Sakaki Y (Dec 1989). "The organization and the complete nucleotide sequence of the human NADH-cytochrome b5 reductase gene". Gene80 (2): 353–61. doi:10.1016/0378-1119(89)90299-0. PMID2479590.
Dailey HA, Strittmatter P (1979). "Modification and identification of cytochrome b5 carboxyl groups involved in protein-protein interaction with cytochrome b5 reductase.". J. Biol. Chem.254 (12): 5388–96. PMID221468.
Malkinson AM, Siegel D, Forrest GL, et al. (1992). "Elevated DT-diaphorase activity and messenger RNA content in human non-small cell lung carcinoma: relationship to the response of lung tumor xenografts to mitomycin Cł.". Cancer Res.52 (17): 4752–7. PMID1324793.
Shirabe K, Yubisui T, Borgese N, et al. (1992). "Enzymatic instability of NADH-cytochrome b5 reductase as a cause of hereditary methemoglobinemia type I (red cell type).". J. Biol. Chem.267 (28): 20416–21. PMID1400360.
Yubisui T, Shirabe K, Takeshita M, et al. (1991). "Structural role of serine 127 in the NADH-binding site of human NADH-cytochrome b5 reductase.". J. Biol. Chem.266 (1): 66–70. PMID1898726.
Shirabe K, Yubisui T, Nishino T, Takeshita M (1991). "Role of cysteine residues in human NADH-cytochrome b5 reductase studied by site-directed mutagenesis. Cys-273 and Cys-283 are located close to the NADH-binding site but are not catalytically essential.". J. Biol. Chem.266 (12): 7531–6. PMID2019583.
Kobayashi Y, Fukumaki Y, Yubisui T, et al. (1990). "Serine-proline replacement at residue 127 of NADH-cytochrome b5 reductase causes hereditary methemoglobinemia, generalized type.". Blood75 (7): 1408–13. PMID2107882.
Strittmatter P, Hackett CS, Korza G, Ozols J (1991). "Characterization of the covalent cross-links of the active sites of amidinated cytochrome b5 and NADH:cytochrome b5 reductase.". J. Biol. Chem.265 (35): 21709–13. PMID2123873.
Murakami K, Yubisui T, Takeshita M, Miyata T (1989). "The NH2-terminal structures of human and rat liver microsomal NADH-cytochrome b5 reductases.". J. Biochem.105 (2): 312–7. PMID2498303.
Vieira LM, Kaplan JC, Kahn A, Leroux A (1995). "Four new mutations in the NADH-cytochrome b5 reductase gene from patients with recessive congenital methemoglobinemia type II.". Blood85 (8): 2254–62. PMID7718898.
Shirabe K, Fujimoto Y, Yubisui T, Takeshita M (1994). "An in-frame deletion of codon 298 of the NADH-cytochrome b5 reductase gene results in hereditary methemoglobinemia type II (generalized type). A functional implication for the role of the COOH-terminal region of the enzyme.". J. Biol. Chem.269 (8): 5952–7. PMID8119939.