Seroatlas · Human Serome Atlas

CYP8B1

7-alpha-hydroxycholest-4-en-3-one 12-alpha-hydroxylase

Also known as: CP8B1_HUMAN, CYP12

Cross-references: UniProt · Ensembl · Human Protein Atlas · GeneCards · NCBI Gene

Protein identityUniProt · HPA

UniProt accession
Q9UNU6
Gene
CYP8B1
Ensembl
ENSG00000180432
Chromosome
3
Canonical length
501 aa
Protein class
Enzymes, Metabolic proteins, Predicted intracellular proteins, Predicted membrane proteins

OverviewNCBI Gene

This gene 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. This endoplasmic reticulum membrane protein catalyzes the conversion of 7 alpha-hydroxy-4-cholesten-3-one into 7-alpha,12-alpha-dihydroxy-4-cholesten-3-one. The balance between these two steroids determines the relative amounts of cholic acid and chenodeoxycholic acid both of which are secreted in the bile and affect the solubility of cholesterol. This gene is unique among the cytochrome P450 genes in that it is intronless. [provided by RefSeq, Jul 2008]

Canonical amino-acid sequenceUniProt

501 residues, UniProt reviewed canonical sequence.

>Q9UNU6|CYP8B1
     1  MVLWGPVLGA LLVVIAGYLC LPGMLRQRRP WEPPLDKGTV PWLGHAMAFR KNMFEFLKRM
    61  RTKHGDVFTV QLGGQYFTFV MDPLSFGSIL KDTQRKLDFG QYAKKLVLKV FGYRSVQGDH
   121  EMIHSASTKH LRGDGLKDLN ETMLDSLSFV MLTSKGWSLD ASCWHEDSLF RFCYYILFTA
   181  GYLSLFGYTK DKEQDLLQAG ELFMEFRKFD LLFPRFVYSL LWPREWLEVG RLQRLFHKML
   241  SVSHSQEKEG ISNWLGNMLQ FLREQGVPSA MQDKFNFMML WASQGNTGPT SFWALLYLLK
   301  HPEAIRAVRE EATQVLGEAR LETKQSFAFK LGALQHTPVL DSVVEETLRL RAAPTLLRLV
   361  HEDYTLKMSS GQEYLFRHGD ILALFPYLSV HMDPDIHPEP TVFKYDRFLN PNGSRKVDFF
   421  KTGKKIHHYT MPWGSGVSIC PGRFFALSEV KLFILLMVTH FDLELVDPDT PLPHVDPQRW
   481  GFGTMQPSHD VRFRYRLHPT E

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against CYP8B1 can act on the native protein depends on physical access: surface and secreted proteins are reachable by circulating antibodies, intracellular proteins usually are not.

Antibody reachability
Other membrane
Secreted
No
Transmembrane segments
1
Mean surface accessibility (rSASA)
0.24
Highest tissue expression
378 nTPM

Expression across tissuesHPA

Tissue

  • liver: 378 nTPM
  • kidney: 14 nTPM
  • epididymis: 0.8 nTPM
  • gallbladder: 0.5 nTPM
  • placenta: 0.4 nTPM
  • skin: 0.4 nTPM

Single-cell type

  • hepatocytes: 1,054 nCPM
  • extravillous trophoblasts: 65 nCPM
  • lymphatic endothelial cells: 32 nCPM
  • syncytiotrophoblasts: 29 nCPM
  • migrating cytotrophoblasts: 24 nCPM
  • epicardial cells: 14 nCPM

Immune cell

  • basophil: 0.2 nTPM
  • classical monocyte: 0 nTPM
  • eosinophil: 0 nTPM
  • gdT-cell: 0 nTPM
  • intermediate monocyte: 0 nTPM
  • MAIT T-cell: 0 nTPM

Brain region

  • hippocampal formation: 1.4 nTPM
  • amygdala: 1.3 nTPM
  • thalamus: 1.3 nTPM
  • basal ganglia: 1.2 nTPM
  • cerebral cortex: 1.2 nTPM
  • hypothalamus: 1.2 nTPM

Genetic constraint and essentialitygnomAD · DepMap

Does the body need this protein intact? Low LOEUF or a strong DepMap dependency means loss or blockade of the protein is likely to be felt.

gnomAD LOEUF (loss-of-function intolerance)
1.19
gnomAD pLI
0
gnomAD missense Z
0.07
DepMap mean gene effect
-0.08
DepMap dependency class
none

Cancer expressionTCGA

Across TCGA tumor cohorts, this protein is over-expressed in roughly 4% of surveyed tumor types (aggregate summary; per-cohort expression, alteration, and survival load in the interactive view).

OntologyGO

Biological processes

Molecular functions

Cellular components

Protein domainsUniProt · Pfam · InterPro

KeywordsUniProt

Antibody and autoantibody relevanceSeroatlas analysis

Seroatlas reads CYP8B1 as an antibody target. Whether an autoantibody or antibody against CYP8B1 could matter depends on whether native CYP8B1 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

CYP8B1 is annotated as predominantly intracellular. Intracellular proteins are common autoantibody markers, becoming visible to the immune system after cell injury or altered processing, but are usually markers of disease rather than direct drivers.

Annotation status

The present source text does not explicitly label CYP8B1 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/CYP8B1. Study-independent annotations aggregated from UniProt, Human Protein Atlas, PubMed, IEDB, Pfam, InterPro, Gene Ontology, AlphaFold, gnomAD, DepMap, ClinVar, TCGA. Catalog release seroatlas-reviewed-human-uniprot-20260313.

Seroatlas is the reference for exploring autoantibody and antibody serology at the human-protein level: the autoreactome and human serome, multiplex serology (HuProt, HuScan, VirScan, PhIP-Seq).

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