IUBMB Enzyme Nomenclature


Accepted name: 7-dehydrocholesterol reductase

Reaction: cholesterol + NADP+ = cholesta-5,7-dien-3β-ol + NADPH + H+

For diagram of reaction click here.

Other name(s): DAF-36 (gene name); DHCR7 (gene name); 7-DHC reductase; 7-dehydrocholesterol dehydrogenase/cholesterol oxidase; Δ7-sterol reductase

Systematic name: cholesterol:NADP+ Δ7-oxidoreductase

Comments: In mammals the enzyme is part of the cholesterol biosynthesis pathway [2] and catalyses the reduction reaction. In the nematode Caenorhabditis elegans the enzyme catalyses the oxidation reaction as part of the biosynthesis of dafachronic acids that are important for control of developmental timing and longevity [3,4].

Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, CAS registry number: 9080-21-1


1. Dempsey, M.E., Seaton, J.D., Schroepfer, G.J. and Trockman, R.W. The intermediary role of Δ5,7-cholestadien-3β-ol in cholesterol biosynthesis. J. Biol. Chem. 239 (1964) 1381-1387. [PMID: 14189869]

2. Moebius, F.F., Fitzky, B.U., Lee, J.N., Paik, Y.K. and Glossmann, H. Molecular cloning and expression of the human Δ7-sterol reductase. Proc. Natl. Acad. Sci. USA 95 (1998) 1899-1902. [PMID: 9465114]

3. Yoshiyama-Yanagawa, T., Enya, S., Shimada-Niwa, Y., Yaguchi, S., Haramoto, Y., Matsuya, T., Shiomi, K., Sasakura, Y., Takahashi, S., Asashima, M., Kataoka, H. and Niwa, R. The conserved Rieske oxygenase DAF-36/Neverland is a novel cholesterol-metabolizing enzyme. J. Biol. Chem. 286 (2011) 25756-25762. [PMID: 21632547]

4. Wollam, J., Magomedova, L., Magner, D.B., Shen, Y., Rottiers, V., Motola, D.L., Mangelsdorf, D.J., Cummins, C.L. and Antebi, A. The Rieske oxygenase DAF-36 functions as a cholesterol 7-desaturase in steroidogenic pathways governing longevity. Aging Cell 10 (2011) 879-884. [PMID: 21749634]

5. Najle, S.R., Nusblat, A.D., Nudel, C.B. and Uttaro, A.D. The sterol-C7 desaturase from the ciliate Tetrahymena thermophila is a Rieske oxygenase, which is highly conserved in animals. Mol Biol Evol 30 (2013) 1630-1643. [PMID: 23603937]

[EC created 1972, modified 2013]

Return to EC 1.3.1 home page
Return to EC 1.3 home page
Return to EC 1 home page
Return to Enzymes home page
Return to IUBMB Biochemical Nomenclature home page