Seroatlas · Human Serome Atlas

CT45A9

Cancer/testis antigen family 45 member A9

Also known as: CT459_HUMAN

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

Protein identityUniProt · HPA

UniProt accession
P0DMV2
Gene
CT45A9
Ensembl
ENSG00000270946
Chromosome
X
Canonical length
189 aa
Protein class
Predicted intracellular proteins
Subcellular location
Nucleoplasm,Nucleoli

OverviewNCBI Gene

This gene represents one of a cluster of several similar genes located on the q arm of chromosome X. The genes in this cluster encode members of the cancer/testis (CT) family of antigens, and are distinct from other CT antigens. These antigens are thought to be novel therapeutic targets for human cancers. [provided by RefSeq, Apr 2014]

Canonical amino-acid sequenceUniProt

189 residues, UniProt reviewed canonical sequence.

>P0DMV2|CT45A9
     1  MTDKTEKVAV DPETVFKRPR ECDSPSYQKR QRMALLARKQ GAGDSLIAGS AMSKEKKLMT
    61  GHAIPPSQLD SQIDDFTGFS KDRMMQKPGS NAPVGGNVTS SFSGDDLECR ETAFSPKSQQ
   121  EINADIKRQL VKELRCVGQK YEKIFEMLEG VQGPTAVRKR FFESIIKEAA RCMRRDFVKH
   181  LKKKLKRMI

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against CT45A9 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
Unknown
Secreted
No
Transmembrane segments
0
Mean surface accessibility (rSASA)
0.55
Highest tissue expression
0.8 nTPM

Expression across tissuesHPA

Tissue

  • testis: 0.8 nTPM
  • basal ganglia: 0.2 nTPM
  • hippocampal formation: 0.1 nTPM
  • hypothalamus: 0.1 nTPM
  • midbrain: 0.1 nTPM
  • spinal cord: 0.1 nTPM

Single-cell type

  • differentiating spermatogonia: 0.1 nCPM
  • early primary spermatocytes: 0.1 nCPM
  • vascular endothelial cells: 0.1 nCPM
  • adipocytes: 0 nCPM
  • adrenal cortex cells: 0 nCPM
  • adrenal medulla 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

  • thalamus: 0.4 nTPM
  • amygdala: 0.2 nTPM
  • hippocampal formation: 0.2 nTPM
  • midbrain: 0.2 nTPM
  • cerebral cortex: 0.1 nTPM
  • medulla oblongata: 0.1 nTPM

Protein domainsUniProt · Pfam · InterPro

Antibody and autoantibody relevanceSeroatlas analysis

Seroatlas reads CT45A9 as an antibody target. Whether an autoantibody or antibody against CT45A9 could matter depends on whether native CT45A9 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

CT45A9 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 CT45A9 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/CT45A9. 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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