Seroatlas · Human Serome Atlas

CYP27B1

25-hydroxyvitamin D-1 alpha hydroxylase, mitochondrial

Also known as: CP27B_HUMAN, CYP1, P450c1, PDDR, VDD1

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

Protein identityUniProt · HPA

UniProt accession
O15528
Gene
CYP27B1
Ensembl
ENSG00000111012
Chromosome
12
Canonical length
508 aa
Protein class
Disease related genes, Enzymes, Human disease related genes, Metabolic proteins, Potential drug targets, Predicted intracellular 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. The protein encoded by this gene localizes to the inner mitochondrial membrane where it hydroxylates 25-hydroxyvitamin D3 at the 1alpha position. This reaction synthesizes 1alpha,25-dihydroxyvitamin D3, the active form of vitamin D3, which binds to the vitamin D receptor and regulates calcium metabolism. Thus this enzyme regulates the level of biologically active vitamin D and plays an important role in calcium homeostasis. Mutations in this gene can result in vitamin D-dependent rickets type I. [provided by RefSeq, Jul 2008]

Canonical amino-acid sequenceUniProt

508 residues, UniProt reviewed canonical sequence.

>O15528|CYP27B1
     1  MTQTLKYASR VFHRVRWAPE LGASLGYREY HSARRSLADI PGPSTPSFLA ELFCKGGLSR
    61  LHELQVQGAA HFGPVWLASF GTVRTVYVAA PALVEELLRQ EGPRPERCSF SPWTEHRRCR
   121  QRACGLLTAE GEEWQRLRSL LAPLLLRPQA AARYAGTLNN VVCDLVRRLR RQRGRGTGPP
   181  ALVRDVAGEF YKFGLEGIAA VLLGSRLGCL EAQVPPDTET FIRAVGSVFV STLLTMAMPH
   241  WLRHLVPGPW GRLCRDWDQM FAFAQRHVER REAEAAMRNG GQPEKDLESG AHLTHFLFRE
   301  ELPAQSILGN VTELLLAGVD TVSNTLSWAL YELSRHPEVQ TALHSEITAA LSPGSSAYPS
   361  ATVLSQLPLL KAVVKEVLRL YPVVPGNSRV PDKDIHVGDY IIPKNTLVTL CHYATSRDPA
   421  QFPEPNSFRP ARWLGEGPTP HPFASLPFGF GKRSCMGRRL AELELQMALA QILTHFEVQP
   481  EPGAAPVRPK TRTVLVPERS INLQFLDR

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against CYP27B1 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
0
Mean surface accessibility (rSASA)
0.27
Highest tissue expression
19 nTPM

Expression across tissuesHPA

Tissue

  • kidney: 19 nTPM
  • thyroid gland: 5.3 nTPM
  • retina: 3.1 nTPM
  • pancreas: 2.8 nTPM
  • urinary bladder: 2 nTPM
  • adrenal gland: 1.4 nTPM

Single-cell type

  • breast lactating cells: 17 nCPM
  • proximal tubule cells: 7.2 nCPM
  • epididymal efferent duct absorptive cells: 6.4 nCPM
  • pancreatic acinar cells: 5 nCPM
  • esophageal basal cells: 4.8 nCPM
  • epicardial cells: 4.5 nCPM

Immune cell

  • MAIT T-cell: 1.2 nTPM
  • memory CD8 T-cell: 0.2 nTPM
  • memory CD4 T-cell: 0.1 nTPM
  • naive CD4 T-cell: 0.1 nTPM
  • naive CD8 T-cell: 0.1 nTPM
  • basophil: 0 nTPM

Brain region

  • cerebral cortex: 0.4 nTPM
  • white matter: 0.4 nTPM
  • amygdala: 0.2 nTPM
  • basal ganglia: 0.2 nTPM
  • cerebellum: 0.2 nTPM
  • hippocampal formation: 0.2 nTPM

DiseaseUniProt · ClinVar · IEDB · PubMed

Four sources answering four different questions about CYP27B1.

Disease | AllUniProt

Conditions CYP27B1 is implicated in, by any mechanism.

  • Rickets vitamin D-dependent 1A (VDDR1A) MIM:264700

Disease | GeneticClinVar

106 pathogenic / likely-pathogenic of 577 ClinVar records.

Conditions with pathogenic or likely-pathogenic variants.

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)
0.98
gnomAD pLI
0
gnomAD missense Z
0.07
DepMap mean gene effect
-0.27
DepMap dependency class
selective

Cancer expressionTCGA

Across TCGA tumor cohorts, this protein is over-expressed in roughly 6% 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 CYP27B1 as an antibody target. Whether an autoantibody or antibody against CYP27B1 could matter depends on whether native CYP27B1 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

CYP27B1 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 CYP27B1 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/CYP27B1. 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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