Seroatlas · Human Serome Atlas

CT45A3

Cancer/testis antigen family 45 member A3

Also known as: CT45-3, CT45-4, CT45.3, CT45.4, CT453_HUMAN, CT45A4

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

Protein identityUniProt · HPA

UniProt accession
Q8NHU0
Gene
CT45A3
Ensembl
ENSG00000269096
Chromosome
X
Canonical length
189 aa
Protein class
Predicted intracellular proteins
Subcellular location
Nucleoplasm,Nucleoli

OverviewNCBI Gene

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

Canonical amino-acid sequenceUniProt

189 residues, UniProt reviewed canonical sequence.

>Q8NHU0|CT45A3
     1  MTDKTEKVAV DPETVFKRPR ECDSPSYQKR QRMALLARKQ GAGDSLIAGS AMSKEKKLMT
    61  GHAIPPSQLD SQIDDFTGFS KDRMMQKPGS NAPVGGNVTS SFSGDDLECR ETASSPKSQR
   121  EINADIKRKL VKELRCVGQK YEKIFEMLEG VQGPTAVRKR FFESIIKEAA RCMRRDFVKH
   181  LKKKLKRMI

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against CT45A3 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)
0.56
Highest tissue expression
6.1 nTPM

Expression across tissuesHPA

Tissue

  • testis: 6.1 nTPM
  • hippocampal formation: 1 nTPM
  • amygdala: 0.9 nTPM
  • spinal cord: 0.8 nTPM
  • basal ganglia: 0.7 nTPM
  • hypothalamus: 0.7 nTPM

Single-cell type

  • differentiating spermatogonia: 1.1 nCPM
  • early primary spermatocytes: 0.8 nCPM
  • early spermatids: 0.1 nCPM
  • undifferentiated spermatogonia: 0.1 nCPM
  • adipocytes: 0 nCPM
  • adrenal cortex cells: 0 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

  • pons: 0.7 nTPM
  • medulla oblongata: 0.6 nTPM
  • basal ganglia: 0.4 nTPM
  • amygdala: 0.3 nTPM
  • hippocampal formation: 0.3 nTPM
  • thalamus: 0.3 nTPM

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

Cellular components

Protein domainsUniProt · Pfam · InterPro

KeywordsUniProt

Antibody and autoantibody relevanceSeroatlas analysis

Seroatlas reads CT45A3 as an antibody target. Whether an autoantibody or antibody against CT45A3 could matter depends on whether native CT45A3 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

CT45A3 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 CT45A3 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/CT45A3. 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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