Seroatlas · Human Serome Atlas

PNMA3

Paraneoplastic antigen Ma3

Also known as: MA3, MA5, MGC132756, MGC132758, PNMA3_HUMAN

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

Protein identityUniProt · HPA

UniProt accession
Q9UL41
Gene
PNMA3
Ensembl
ENSG00000183837
Chromosome
X
Canonical length
463 aa
Protein class
Predicted intracellular proteins

OverviewNCBI Gene

The protein encoded by this gene belongs to the paraneoplastic antigen MA (PNMA) family, which shares homology with retroviral Gag proteins. The PNMA antigens are highly expressed in the brain and also in a range of tumors associated with serious neurological phenotypes. PMID:16407312 reports the presence of a functional -1 ribosomal frameshift signal (consisting of a heptanucleotide shift motif followed 3' by a pseudoknot structure) in this gene, however, the frame-shifted product has not been characterized. Alternatively spliced transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, Sep 2013]

Canonical amino-acid sequenceUniProt

463 residues, UniProt reviewed canonical sequence.

>Q9UL41|PNMA3
     1  MPLTLLQDWC RGEHLNTRRC MLILGIPEDC GEDEFEETLQ EACRHLGRYR VIGRMFRREE
    61  NAQAILLELA QDIDYALLPR EIPGKGGPWE VIVKPRNSDG EFLNRLNRFL EEERRTVSDM
   121  NRVLGSDTNC SAPRVTISPE FWTWAQTLGA AVQPLLEQML YRELRVFSGN TISIPGALAF
   181  DAWLEHTTEM LQMWQVPEGE KRRRLMECLR GPALQVVSGL RASNASITVE ECLAALQQVF
   241  GPVESHKIAQ VKLCKAYQEA GEKVSSFVLR LEPLLQRAVE NNVVSRRNVN QTRLKRVLSG
   301  ATLPDKLRDK LKLMKQRRKP PGFLALVKLL REEEEWEATL GPDRESLEGL EVAPRPPARI
   361  TGVGAVPLPA SGNSFDARPS QGYRRRRGRG QHRRGGVARA GSRGSRKRKR HTFCYSCGED
   421  GHIRVQCINP SNLLLVKQKK QAAVESGNGN WAWDKSHPKS KAK

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against PNMA3 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)
0.43
Highest tissue expression
46 nTPM

Expression across tissuesHPA

Tissue

  • epididymis: 46 nTPM
  • cerebral cortex: 30 nTPM
  • hypothalamus: 18 nTPM
  • pituitary gland: 14 nTPM
  • testis: 14 nTPM
  • cerebellum: 11 nTPM

Single-cell type

  • epididymal principal cells: 105 nCPM
  • sertoli cells: 82 nCPM
  • other brain neurons: 54 nCPM
  • brain excitatory neurons: 47 nCPM
  • brain inhibitory neurons: 44 nCPM
  • epididymal efferent duct absorptive cells: 33 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: 34 nTPM
  • white matter: 20 nTPM
  • pons: 19 nTPM
  • hypothalamus: 19 nTPM
  • medulla oblongata: 18 nTPM
  • basal ganglia: 16 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 missense Z
0.75
DepMap mean gene effect
0.07
DepMap dependency class
selective

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 PNMA3 as an antibody target. Whether an autoantibody or antibody against PNMA3 could matter depends on whether native PNMA3 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

PNMA3 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 PNMA3 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/PNMA3. 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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