Seroatlas · Human Serome Atlas

SRD5A2

3-oxo-5-alpha-steroid 4-dehydrogenase 2

Also known as: S5A2_HUMAN

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

Protein identityUniProt · HPA

UniProt accession
P31213
Gene
SRD5A2
Ensembl
ENSG00000277893
Chromosome
2
Canonical length
254 aa
Protein class
Cancer-related genes, Disease related genes, Enzymes, FDA approved drug targets, Human disease related genes, Metabolic proteins, Predicted membrane proteins, Transporters

OverviewNCBI Gene

This gene encodes a microsomal protein expressed at high levels in androgen-sensitive tissues such as the prostate. The encoded protein is active at acidic pH and is sensitive to the 4-azasteroid inhibitor finasteride. Deficiencies in this gene can result in male pseudohermaphroditism, specifically pseudovaginal perineoscrotal hypospadias (PPSH). [provided by RefSeq, Jul 2008]

Canonical amino-acid sequenceUniProt

254 residues, UniProt reviewed canonical sequence.

>P31213|SRD5A2
     1  MQVQCQQSPV LAGSATLVAL GALALYVAKP SGYGKHTESL KPAATRLPAR AAWFLQELPS
    61  FAVPAGILAR QPLSLFGPPG TVLLGLFCLH YFHRTFVYSL LNRGRPYPAI LILRGTAFCT
   121  GNGVLQGYYL IYCAEYPDGW YTDIRFSLGV FLFILGMGIN IHSDYILRQL RKPGEISYRI
   181  PQGGLFTYVS GANFLGEIIE WIGYALATWS LPALAFAFFS LCFLGLRAFH HHRFYLKMFE
   241  DYPKSRKALI PFIF

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against SRD5A2 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
4
Mean surface accessibility (rSASA)
0.28
Highest tissue expression
57 nTPM

Expression across tissuesHPA

Tissue

  • liver: 57 nTPM
  • epididymis: 22 nTPM
  • fallopian tube: 19 nTPM
  • seminal vesicle: 17 nTPM
  • prostate: 16 nTPM
  • vagina: 1.8 nTPM

Single-cell type

  • prostatic club cells: 144 nCPM
  • early spermatids: 97 nCPM
  • fallopian tube ciliated cells: 90 nCPM
  • late spermatids: 85 nCPM
  • epididymal principal cells: 47 nCPM
  • hepatocytes: 43 nCPM

Immune cell

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

Brain region

  • midbrain: 2.2 nTPM
  • basal ganglia: 0.1 nTPM
  • cerebellum: 0.1 nTPM
  • hypothalamus: 0.1 nTPM
  • medulla oblongata: 0.1 nTPM
  • thalamus: 0.1 nTPM

DiseaseUniProt · ClinVar · IEDB · PubMed

Four sources answering four different questions about SRD5A2.

Disease | AllUniProt

Conditions SRD5A2 is implicated in, by any mechanism.

  • Pseudovaginal perineoscrotal hypospadias (PPSH) MIM:264600

Disease | GeneticClinVar

97 pathogenic / likely-pathogenic of 337 ClinVar records.

Conditions with pathogenic or likely-pathogenic variants.

Cancer expressionTCGA

Across TCGA tumor cohorts, this protein is over-expressed in roughly 3% 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 SRD5A2 as an antibody target. Whether an autoantibody or antibody against SRD5A2 could matter depends on whether native SRD5A2 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

SRD5A2 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 SRD5A2 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/SRD5A2. 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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