Seroatlas · Human Serome Atlas

SPATA3

Spermatogenesis-associated protein 3

Also known as: SPTA3_HUMAN, TSARG1

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

Protein identityUniProt · HPA

UniProt accession
Q8NHX4
Gene
SPATA3
Ensembl
ENSG00000173699
Chromosome
2
Canonical length
192 aa
Protein class
Predicted intracellular proteins, Predicted membrane proteins

OverviewNCBI Gene

Located in sperm flagellum. [provided by Alliance of Genome Resources, Jul 2025]

Canonical amino-acid sequenceUniProt

192 residues, UniProt reviewed canonical sequence.

>Q8NHX4|SPATA3
     1  MKKVKKKRSE ARRHRDSTSQ HASSNSTSQQ PSPESTPQQP SPESTPQQPS PESTPQHSSL
    61  ETTSRQPAFQ ALPAPEIRRS SCCLLSPDAN VKAAPQSRKA GPLIRAGPHS CSCATCPCSS
   121  ACWRRLGLCH SRIFDVLLPR DWQMAPGRGL PNLLTFYRKS SRKPSSHRNA CPPSPRNCGC
   181  GSGGSRSCLL HH

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against SPATA3 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
Intracellular
Secreted
No
Transmembrane segments
0
Mean surface accessibility (rSASA)
0.7
Highest tissue expression
169 nTPM

Expression across tissuesHPA

Tissue

  • testis: 169 nTPM
  • bone marrow: 0.3 nTPM
  • basal ganglia: 0.2 nTPM
  • cerebral cortex: 0.2 nTPM
  • epididymis: 0.2 nTPM
  • hypothalamus: 0.2 nTPM

Single-cell type

  • late spermatids: 10,406 nCPM
  • early spermatids: 1,043 nCPM
  • late primary spermatocytes: 148 nCPM
  • oocytes: 18 nCPM
  • leydig cells: 13 nCPM
  • sertoli cells: 12 nCPM

Immune cell

  • neutrophil: 0.3 nTPM
  • basophil: 0.2 nTPM
  • classical monocyte: 0 nTPM
  • eosinophil: 0 nTPM
  • gdT-cell: 0 nTPM
  • intermediate monocyte: 0 nTPM

Brain region

  • thalamus: 3.9 nTPM
  • white matter: 3.3 nTPM
  • cerebellum: 3.2 nTPM
  • basal ganglia: 3.1 nTPM
  • midbrain: 3 nTPM
  • pons: 3 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)
1.55
gnomAD pLI
0
gnomAD missense Z
0
DepMap mean gene effect
0.07
DepMap dependency class
none

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

Cellular components

Protein domainsUniProt · Pfam · InterPro

  • Spermatogenesis-associated protein 3
  • Spermatogenesis-associated protein 3 family

KeywordsUniProt

Antibody and autoantibody relevanceSeroatlas analysis

Seroatlas reads SPATA3 as an antibody target. Whether an autoantibody or antibody against SPATA3 could matter depends on whether native SPATA3 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

SPATA3 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 SPATA3 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/SPATA3. 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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