Seroatlas · Human Serome Atlas

CTAG2

Cancer/testis antigen 2

Also known as: CAMEL, CT6.2a, CT6.2b, CTAG2_HUMAN, ESO2, LAGE-1, LAGE-1a, LAGE-1b, LAGE1, MGC138724, MGC3803

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

Protein identityUniProt · HPA

UniProt accession
O75638
Gene
CTAG2
Ensembl
ENSG00000126890
Chromosome
X
Canonical length
210 aa
Protein class
Cancer-related genes, Predicted intracellular proteins
Subcellular location
Nucleoplasm,Vesicles

OverviewNCBI Gene

This gene encodes an autoimmunogenic tumor antigen that belongs to the ESO/LAGE family of cancer-testis antigens. This protein is expressed in a wide array of cancers including melanoma, breast cancer, bladder cancer and prostate cancer. This protein is also expressed in normal testis tissue. An alternative open reading frame product of this gene has been described in PMID:10399963. This alternate protein, termed CAMEL, is a tumor antigen that is recognized by melanoma-specific cytotoxic T-lymphocytes. Alternate splicing results in multiple transcript variants. [provided by RefSeq, Sep 2013]

Canonical amino-acid sequenceUniProt

210 residues, UniProt reviewed canonical sequence.

>O75638|CTAG2
     1  MQAEGRGTGG STGDADGPGG PGIPDGPGGN AGGPGEAGAT GGRGPRGAGA ARASGPRGGA
    61  PRGPHGGAAS AQDGRCPCGA RRPDSRLLEL HITMPFSSPM EAELVRRILS RDAAPLPRPG
   121  AVLKDFTVSG NLLFMSVRDQ DREGAGRMRV VGWGLGSASP EGQKARDLRT PKHKVSEQRP
   181  GTPGPPPPEG AQGDGCRGVA FNVMFSAPHI

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against CTAG2 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)
0.64
Highest tissue expression
10 nTPM

Expression across tissuesHPA

Tissue

  • testis: 10 nTPM
  • heart muscle: 5 nTPM
  • skeletal muscle: 3 nTPM
  • thymus: 2.8 nTPM
  • placenta: 2.4 nTPM
  • pancreas: 1.8 nTPM

Single-cell type

  • differentiating spermatogonia: 89 nCPM
  • undifferentiated spermatogonia: 51 nCPM
  • early primary spermatocytes: 36 nCPM
  • submucosal glandular cells: 15 nCPM
  • extravillous trophoblasts: 14 nCPM
  • oocytes: 14 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: 0.5 nTPM
  • medulla oblongata: 0.3 nTPM
  • pons: 0.2 nTPM
  • white matter: 0.1 nTPM
  • amygdala: 0 nTPM
  • basal ganglia: 0 nTPM

DiseaseUniProt · ClinVar · IEDB · PubMed

Four sources answering four different questions about CTAG2.

Disease | ImmuneIEDB

Conditions an epitope on CTAG2 was assayed in.

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)
1.87
gnomAD pLI
0.1
gnomAD missense Z
-0.49
DepMap mean gene effect
-0.04
DepMap dependency class
selective

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

Cellular components

Protein domainsUniProt · Pfam · InterPro

Antibody and autoantibody relevanceSeroatlas analysis

Seroatlas reads CTAG2 as an antibody target. Whether an autoantibody or antibody against CTAG2 could matter depends on whether native CTAG2 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

CTAG2 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 CTAG2 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/CTAG2. 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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