CYP3A5
cytochrome P450 family 3 subfamily A member 5
Gene summary
A protein-coding gene on chromosome 7 (drug metabolism (phase i)). Encodes a member of the cytochrome P450 superfamily of enzymes. The cytochrome P450 proteins are monooxygenases which catalyze many reactions involved in drug metabolism and synthesis of cholesterol, steroids and other lipids.
Source: NCBI Gene, accessed 2026-10-07.
Protein reference (UniProt)
- Protein
Cytochrome P450 3A5
- Function (excerpt)
A cytochrome P450 monooxygenase involved in the metabolism of steroid hormones and vitamins. Mechanistically, uses molecular oxygen inserting one oxygen atom into a substrate, and reducing the second into a water molecule, with two electrons provided by NADPH via cytochrome P450 reductase (NADPH--hemoprotein reductase). Catalyzes the hydroxylation of carbon-hydrogen bonds. Exhibits high catalytic activity for the formation of catechol estrogens from 17beta-estradiol (E2) and estrone (E1), namely 2-hydroxy E1 and E2. Catalyzes 6beta-hydroxylation of the steroid hormones testosterone, progesterone, and androstenedione. Catalyzes the oxidative conversion of all-trans-retinol to all-trans-retinal, a rate-limiting step for the biosynthesis of all-trans-retinoic acid (atRA). Further metabolizes all trans-retinoic acid (atRA) to 4-hydroxyretinoate and may play a role in hepatic atRA clearance.
- Pathway
Steroid hormone biosynthesis. Cofactor metabolism; retinol metabolism.
- Subcellular location
Endoplasmic reticulum membrane; Microsome membrane.
Source: UniProtKB/Swiss-Prot P20815, release 2026_03, licensed CC BY 4.0. This is the protein’s normal biology, not evidence about post-drug syndromes; associated conditions are inherited disorders of the gene, not PFS, PSSD or PRSD.
Why its pathway is in the library
Phase I enzymes determine exposure to finasteride, SSRIs, and other implicated drugs; variation here shapes the likelihood and persistence of adverse effects.
Written for the whole drug metabolism family, not for CYP3A5 specifically.
Mentioned in 1 corpus record
- Peer-reviewed paper
Finasteride Concentrations and Prostate Cancer Risk: Results from the Prostate Cancer Prevention Trial
Cindy H. Chau, Douglas K. Price, Cathee Till, Phyllis J. Goodman, Xiaohong Chen, Robin J. Leach, Teresa L. Johnson-Pais, Ann Wu Hsing… · PLoS ONE
Using a nested case-control design inside the Prostate Cancer Prevention Trial, the authors measured serum finasteride by validated LC-MS and tested 27 SNPs in finasteride target and metabolism genes for association with drug concentrations. Five SNPs in…
CYP3A4CYP3A5SRD5A2SRD5A3MECH-0432015PFSSystems review · Oct 2026
Also in drug metabolism (phase i)
All 23 genes- CYP2D6
cytochrome P450 family 2 subfamily D member 6 (gene/pseudogene)
chr 22· Drug metabolism· 6 records - COMT
catechol-O-methyltransferase
chr 22· Drug metabolism· 4 records - CYP3A4
cytochrome P450 family 3 subfamily A member 4
chr 7· Drug metabolism· 2 records - CYP2C19
cytochrome P450 family 2 subfamily C member 19
chr 10· Drug metabolism· 1 record - MAOA
monoamine oxidase A
chr X· Drug metabolism· 1 record - AKR1B1
aldo-keto reductase family 1 member B
chr 7· Drug metabolism· Pathway candidate - AKR1B10
aldo-keto reductase family 1 member B10
chr 7· Drug metabolism· Pathway candidate - ALDH1A1
aldehyde dehydrogenase 1 family member A1
chr 9· Drug metabolism· Pathway candidate
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