Reactome: A Curated Pathway Database
THIS SITE IS USED FOR CURATION AND TESTING
IT IS NOT STABLE, IS LINKED TO AN INCOMPLETE DATA SET, AND IS NOT MONITORED FOR PERFORMANCE. WE STRONGLY RECOMMEND THE USE OF OUR PUBLIC SITE

Query author contributions in Reactome

Reactome depends on collaboration between our curation team and outside experts to assemble and peer-review its pathway modules. The integration of ORCID within Reactome enables us to meet a key challenge with authoring, curating and reviewing biological information by incentivizing and crediting the external experts that contribute their expertise and time to the Reactome curation process. More information is available at ORCID and Reactome.

If you have an ORCID ID that is not listed on this page, please forward this information to us and we will update your Reactome pathway records.

Name Email address

Details on Person UniProt:Q16850-1 CYP51A1

Class:IdReferenceIsoform:424684
_chainChangeLogchain:1-503 added on Fri February 6 2015;chain:1-503 for 424684 removed on Fri February 25 2022;chain:1-509 for 424684 added on Fri February 25 2022
_displayNameUniProt:Q16850-1 CYP51A1
_timestamp2025-08-15 21:29:15
chainchain:1-509
checksumF9145DDB65F94091
commentFUNCTION Sterol 14alpha-demethylase that plays a critical role in the cholesterol biosynthesis pathway, being cholesterol the major sterol component in mammalian membranes as well as a precursor for bile acid and steroid hormone synthesis (PubMed:20149798, PubMed:8619637, PubMed:9559662). Cytochrome P450 monooxygenase that catalyzes the three-step oxidative removal of the 14alpha-methyl group (C-32) of sterols such as lanosterol (lanosta-8,24-dien-3beta-ol) and 24,25-dihydrolanosterol (DHL) in the form of formate, and converts the sterols to 4,4-dimethyl-5alpha-cholesta-8,14,24-trien-3beta-ol and 4,4-dimethyl-8,14-cholestadien-3beta-ol, respectively, which are intermediates of cholesterol biosynthesis (PubMed:20149798, PubMed:8619637, PubMed:9559662). Can also demethylate substrates not intrinsic to mammals, such as eburicol (24-methylene-24,25-dihydrolanosterol), but at a lower rate than DHL (PubMed:9559662).CATALYTIC ACTIVITY a 14alpha-methyl steroid + 3 reduced [NADPH--hemoprotein reductase] + 3 O2 = a Delta(14) steroid + formate + 3 oxidized [NADPH--hemoprotein reductase] + 4 H2O + 4 H(+)CATALYTIC ACTIVITY lanosterol + 3 reduced [NADPH--hemoprotein reductase] + 3 O2 = 4,4-dimethyl-5alpha-cholesta-8,14,24-trien-3beta-ol + formate + 3 oxidized [NADPH--hemoprotein reductase] + 4 H2O + 4 H(+)CATALYTIC ACTIVITY 24,25-dihydrolanosterol + 3 reduced [NADPH--hemoprotein reductase] + 3 O2 = 4,4-dimethyl-8,14-cholestadien-3beta-ol + formate + 3 oxidized [NADPH--hemoprotein reductase] + 4 H2O + 4 H(+)CATALYTIC ACTIVITY a 14alpha-methyl steroid + reduced [NADPH--hemoprotein reductase] + O2 = a 14alpha-hydroxymethyl steroid + oxidized [NADPH--hemoprotein reductase] + H2O + H(+)CATALYTIC ACTIVITY a 14alpha-hydroxymethyl steroid + reduced [NADPH--hemoprotein reductase] + O2 = a 14alpha-formyl steroid + oxidized [NADPH--hemoprotein reductase] + 2 H2O + H(+)CATALYTIC ACTIVITY a 14alpha-formyl steroid + reduced [NADPH--hemoprotein reductase] + O2 = a Delta(14) steroid + formate + oxidized [NADPH--hemoprotein reductase] + H2O + 2 H(+)CATALYTIC ACTIVITY lanosterol + reduced [NADPH--hemoprotein reductase] + O2 = 32-hydroxylanosterol + oxidized [NADPH--hemoprotein reductase] + H2O + H(+)CATALYTIC ACTIVITY 32-hydroxylanosterol + reduced [NADPH--hemoprotein reductase] + O2 = 32-oxolanosterol + oxidized [NADPH--hemoprotein reductase] + 2 H2O + H(+)CATALYTIC ACTIVITY 32-oxolanosterol + reduced [NADPH--hemoprotein reductase] + O2 = 4,4-dimethyl-5alpha-cholesta-8,14,24-trien-3beta-ol + formate + oxidized [NADPH--hemoprotein reductase] + H2O + 2 H(+)CATALYTIC ACTIVITY 24,25-dihydrolanosterol + reduced [NADPH--hemoprotein reductase] + O2 = 32-hydroxy-24,25-dihydrolanosterol + oxidized [NADPH--hemoprotein reductase] + H2O + H(+)CATALYTIC ACTIVITY 32-hydroxy-24,25-dihydrolanosterol + reduced [NADPH--hemoprotein reductase] + O2 = 32-oxo-24,25-dihydrolanosterol + oxidized [NADPH--hemoprotein reductase] + 2 H2O + H(+)CATALYTIC ACTIVITY 32-oxo-24,25-dihydrolanosterol + reduced [NADPH--hemoprotein reductase] + O2 = 4,4-dimethyl-8,14-cholestadien-3beta-ol + formate + oxidized [NADPH--hemoprotein reductase] + H2O + 2 H(+)COFACTOR Inhibited by azalanstat. Inhibited by azole antifungal agents ketoconazole, itraconazole and fluconazole.BIOPHYSICOCHEMICAL PROPERTIES Steroid biosynthesis; zymosterol biosynthesis; zymosterol from lanosterol: step 1/6.SUBCELLULAR LOCATION Ubiquitously expressed with highest levels in testis, ovary, adrenal, prostate, liver, kidney and lung.PTM Ubiquitinated by MARCHF6, leading to proteasomal degradation.SIMILARITY Belongs to the cytochrome P450 family.CAUTION It is uncertain whether Met-1 or Met-7 is the initiator.SEQUENCE CAUTION Truncated N-terminus.
created[InstanceEdit:423310] Kanapin, AA
descriptionrecommendedName: fullName evidence="8"Lanosterol 14-alpha demethylase shortName: LDM ecNumber evidence="3 5 6"1.14.14.154 alternativeName: CYPLI alternativeName: Cytochrome P450 51A1 shortName: CYP51A1 alternativeName: Cytochrome P450-14DM shortName: Cytochrome P45014DM alternativeName: Cytochrome P450LI alternativeName: Sterol 14-alpha demethylase
geneNameCYP51A1
CYP51
identifierQ16850
isoformParent
isSequenceChangedFALSE
keyword3D-structure
Alternative splicing
Cholesterol biosynthesis
Cholesterol metabolism
Endoplasmic reticulum
Heme
Iron
Lipid biosynthesis
Lipid metabolism
Membrane
Metal-binding
Microsome
Monooxygenase
Oxidoreductase
Proteomics identification
Reference proteome
Steroid biosynthesis
Steroid metabolism
Sterol biosynthesis
Sterol metabolism
Transmembrane
Transmembrane helix
Ubl conjugation
modified[InstanceEdit:9836292] Weiser, Joel, 2023-05-25
[InstanceEdit:9852000] Weiser, Joel, 2023-11-03
[InstanceEdit:9862192] Weiser, Joel, 2024-02-26
[InstanceEdit:9917590] Weiser, Joel, 2024-08-09
[InstanceEdit:9926675] Weiser, Joel, 2024-11-03
[InstanceEdit:9939033] Weiser, Joel, 2025-02-21
[InstanceEdit:9963647] Weiser, Joel, 2025-08-15
nameCYP51A1
referenceDatabase[ReferenceDatabase:2] UniProt
referenceGene[ReferenceDNASequence:5660082] ENSEMBL:ENSG00000001630 CYP51A1 [Homo sapiens]
secondaryIdentifierCP51A_HUMAN
A0A0C4DFL7
A4D1F8
B2RAI4
B4DJ55
O00770
O00772
Q16784
Q8N1A8
Q99868
sequenceLength509
species[Species:48887] Homo sapiens
variantIdentifierQ16850-1
[Change default viewing format]
No pathways have been reviewed or authored by UniProt:Q16850-1 CYP51A1 (424684)
Follow Reactome