Seroatlas · Human Serome Atlas

HSD3B2

3 beta-hydroxysteroid dehydrogenase/Delta 5-->4-isomerase type 2

Also known as: 3BHS2_HUMAN, SDR11E2

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

Protein identityUniProt · HPA

UniProt accession
P26439
Gene
HSD3B2
Ensembl
ENSG00000203859
Chromosome
1
Canonical length
372 aa
Protein class
Disease related genes, Enzymes, FDA approved drug targets, Human disease related genes, Metabolic proteins, Predicted intracellular proteins, Predicted membrane proteins
Subcellular location
Nucleoli,Endoplasmic reticulum,Microtubules,Cytokinetic bridge,Primary cilium,Primary cilium transition zone

OverviewNCBI Gene

The protein encoded by this gene is a bifunctional enzyme that catalyzes the oxidative conversion of delta(5)-ene-3-beta-hydroxy steroid, and the oxidative conversion of ketosteroids. It plays a crucial role in the biosynthesis of all classes of hormonal steroids. This gene is predominantly expressed in the adrenals and the gonads. Mutations in this gene are associated with 3-beta-hydroxysteroid dehydrogenase, type II, deficiency. Alternatively spliced transcript variants have been found for this gene. [provided by RefSeq, Oct 2009]

Canonical amino-acid sequenceUniProt

372 residues, UniProt reviewed canonical sequence.

>P26439|HSD3B2
     1  MGWSCLVTGA GGLLGQRIVR LLVEEKELKE IRALDKAFRP ELREEFSKLQ NRTKLTVLEG
    61  DILDEPFLKR ACQDVSVVIH TACIIDVFGV THRESIMNVN VKGTQLLLEA CVQASVPVFI
   121  YTSSIEVAGP NSYKEIIQNG HEEEPLENTW PTPYPYSKKL AEKAVLAANG WNLKNGDTLY
   181  TCALRPTYIY GEGGPFLSAS INEALNNNGI LSSVGKFSTV NPVYVGNVAW AHILALRALR
   241  DPKKAPSVRG QFYYISDDTP HQSYDNLNYI LSKEFGLRLD SRWSLPLTLM YWIGFLLEVV
   301  SFLLSPIYSY QPPFNRHTVT LSNSVFTFSY KKAQRDLAYK PLYSWEEAKQ KTVEWVGSLV
   361  DRHKETLKSK TQ

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against HSD3B2 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)
0.23
Highest tissue expression
2,103 nTPM

Expression across tissuesHPA

Tissue

  • adrenal gland: 2,103 nTPM
  • small intestine: 39 nTPM
  • ovary: 9.3 nTPM
  • colon: 7.5 nTPM
  • placenta: 3.4 nTPM
  • testis: 2.7 nTPM

Single-cell type

  • adrenal cortex cells: 2,208 nCPM
  • adrenal medulla cells: 96 nCPM
  • enterocytes: 37 nCPM
  • colonocytes: 5.6 nCPM
  • enteric transient amplifying cells: 3.8 nCPM
  • peritubular myoid cells: 2.9 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

  • cerebral cortex: 3.9 nTPM
  • amygdala: 2.5 nTPM
  • white matter: 2.1 nTPM
  • pons: 2 nTPM
  • thalamus: 2 nTPM
  • medulla oblongata: 1.8 nTPM

DiseaseUniProt · ClinVar · IEDB · PubMed

Four sources answering four different questions about HSD3B2.

Disease | AllUniProt

Conditions HSD3B2 is implicated in, by any mechanism.

Disease | GeneticClinVar

88 pathogenic / likely-pathogenic of 444 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)
1.62
gnomAD pLI
0
gnomAD missense Z
0.66
DepMap mean gene effect
-0.01
DepMap dependency class
none

Cancer expressionTCGA

Across TCGA tumor cohorts, this protein is over-expressed in roughly 2% 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 HSD3B2 as an antibody target. Whether an autoantibody or antibody against HSD3B2 could matter depends on whether native HSD3B2 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

HSD3B2 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 HSD3B2 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/HSD3B2. 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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