Steroid 17-alpha-hydroxylase/17,20 lyase
Named enzymes, including the metabolising cytochromes and the monoamine oxidases.
- Measurements
- 1
- Compounds
- 1
- Binding constants
- 1
- Median pX
- —
I · Identity
What this target is
Its function as UniProt states it, where in a cell the protein is found, and which cell types and tissues transcribe its gene.
Steroid 17-alpha-hydroxylase/17,20 lyase
A cytochrome P450 monooxygenase involved in corticoid and androgen biosynthesis22266943,25301938,27339894,9452426. Catalyzes 17-alpha hydroxylation of C21 steroids, which is common for both pathways. A second oxidative step, required only for androgen synthesis, involves an acyl-carbon cleavage. The 17-alpha hydroxy intermediates, as part of adrenal glucocorticoids biosynthesis pathway, are precursors of cortisol (Probable)25301938,9452426. Hydroxylates steroid hormones, pregnenolone and progesterone to form 17-alpha hydroxy metabolites, followed by the cleavage of the C17-C20 bond to form C19 steroids, dehydroepiandrosterone (DHEA) and androstenedione22266943,25301938,27339894,36640554,9452426. Has 16-alpha hydroxylase activity. Catalyzes 16-alpha hydroxylation of 17-alpha hydroxy pregnenolone, followed by the cleavage of the C17-C20 bond to form 16-alpha-hydroxy DHEA36640554. Also 16-alpha hydroxylates androgens, relevant for estriol synthesis25301938,27339894. 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 (CPR; NADPH-ferrihemoprotein reductase)22266943,25301938,27339894,9452426
Quoted from UniProt’s FUNCTION annotation for P05093 (reviewed). The superscript numbers are UniProt’s own PubMed citations, kept in the sentence and in order, each linking to the paper it names.
What it acts with
STRING’s highest-confidence human functional partners. The combined score mixes several kinds of evidence, so each channel is shown separately — a partner supported by experiment is a different claim from one supported only by text mining, and for a receptor this is where its coupling appears as evidence rather than as assertion.
| Partner | Combined | Experiment | Database | Text mining |
|---|---|---|---|---|
| HSD3B1 | 0.995 | 0.108 | 0.913 | 0.948 |
| HSD3B2 | 0.994 | 0.108 | 0.913 | 0.928 |
| SRD5A1 | 0.992 | 0.000 | 0.900 | 0.929 |
| HSD17B3 | 0.991 | 0.105 | 0.906 | 0.905 |
| SRD5A2 | 0.986 | 0.000 | 0.900 | 0.866 |
| CYB5B | 0.980 | 0.071 | 0.000 | 0.979 |
| CYB5A | 0.979 | 0.071 | 0.000 | 0.978 |
| AKR1C3 | 0.979 | 0.045 | 0.900 | 0.804 |
| HSD17B2 | 0.972 | 0.045 | 0.900 | 0.732 |
| CYP19A1 | 0.971 | 0.052 | 0.906 | 0.614 |
Where it sits in the cell
- Vesicles
Human Protein Atlas, by antibody immunofluorescence in cell lines — a different assay from the expression figures below, which are RNA.
UniProt, curated Endoplasmic reticulum membrane · Microsome membrane
Expression by cell type
Single cell type RNA, the 1 highest of those the Human Protein Atlas reports for this gene. Transcript, not protein, and a cell type rather than a tissue.
- Adrenal cortex cells3,116.7 nCPM
Expression by tissue
The tissues this gene is enriched in, by consensus RNA. A tissue absent from this list is one the Atlas does not call specific for this gene, which is not the same as absent from it.
- adrenal gland8,353.3 nTPM
IV · Evidence
Every measurement at this target
Each row links to the ChEMBL assay it came from.
Equilibrium binding constants 1
Ki and Kd — a concentration at equilibrium. Directly comparable across rows at the same target.
| Target | Class | Type | Value (nM) | pX | Organism | Assay |
|---|---|---|---|---|---|---|
| Steroid 17-alpha-hydroxylase/17,20 lyase | Enzymes | Ki | — no normalized value | — value does not convert to pX | Rattus norvegicus | CHEMBL4687737 |