Seroatlas · Human Serome Atlas

CCR9

C-C chemokine receptor type 9

Also known as: CCR9_HUMAN, CDw199, GPR-9-6, GPR28

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

Protein identityUniProt · HPA

UniProt accession
P51686
Gene
CCR9
Ensembl
ENSG00000173585
Chromosome
3
Canonical length
369 aa
Protein class
CD markers, G-protein coupled receptors, Predicted intracellular proteins, Predicted membrane proteins
Subcellular location
Endoplasmic reticulum,Plasma membrane

OverviewNCBI Gene

The protein encoded by this gene is a G protein-coupled receptor with seven transmembrane domains that belongs to the beta chemokine receptor family. Chemokines and their receptors are key regulators of thymocyte migration and maturation in normal and inflammation conditions. This gene is differentially expressed in T lymphocytes of the small intestine and colon, and its interaction with chemokine 25 contributes to intestinal intra-epithelial lymphocyte homing to the small intestine. This suggests a role for this gene in directing immune responses to different segments of the gastrointestinal tract. This gene and its exclusive ligand, chemokine 25, are overexpressed in a variety of malignant tumors and are closely associated with tumor proliferation, apoptosis, invasion, migration and drug resistance. This gene maps to the chemokine receptor gene cluster. Multiple transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, Aug 2020]

Canonical amino-acid sequenceUniProt

369 residues, UniProt reviewed canonical sequence.

>P51686|CCR9
     1  MTPTDFTSPI PNMADDYGSE STSSMEDYVN FNFTDFYCEK NNVRQFASHF LPPLYWLVFI
    61  VGALGNSLVI LVYWYCTRVK TMTDMFLLNL AIADLLFLVT LPFWAIAAAD QWKFQTFMCK
   121  VVNSMYKMNF YSCVLLIMCI SVDRYIAIAQ AMRAHTWREK RLLYSKMVCF TIWVLAAALC
   181  IPEILYSQIK EESGIAICTM VYPSDESTKL KSAVLTLKVI LGFFLPFVVM ACCYTIIIHT
   241  LIQAKKSSKH KALKVTITVL TVFVLSQFPY NCILLVQTID AYAMFISNCA VSTNIDICFQ
   301  VTQTIAFFHS CLNPVLYVFV GERFRRDLVK TLKNLGCISQ AQWVSFTRRE GSLKLSSMLL
   361  ETTSGALSL

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against CCR9 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
Cell surface
Secreted
No
Transmembrane segments
7
Mean surface accessibility (rSASA)
0.32
Highest tissue expression
121 nTPM

Expression across tissuesHPA

Tissue

  • thymus: 121 nTPM
  • small intestine: 5.3 nTPM
  • duodenum: 3.7 nTPM
  • appendix: 1 nTPM
  • spleen: 1 nTPM
  • choroid plexus: 0.9 nTPM

Single-cell type

  • thymocytes: 31 nCPM
  • cardiomyocytes: 18 nCPM
  • nk-cells: 17 nCPM
  • epicardial cells: 9.1 nCPM
  • myonuclei: 8.8 nCPM
  • innate lymphoid cells: 8.3 nCPM

Immune cell

  • memory B-cell: 24 nTPM
  • naive B-cell: 16 nTPM
  • T-reg: 8.2 nTPM
  • memory CD4 T-cell: 2.8 nTPM
  • total PBMC: 2.7 nTPM
  • memory CD8 T-cell: 2.4 nTPM

Brain region

  • choroid plexus: 1.5 nTPM
  • medulla oblongata: 1.3 nTPM
  • basal ganglia: 1 nTPM
  • cerebral cortex: 1 nTPM
  • pons: 1 nTPM
  • spinal cord: 1 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)
1.13
gnomAD pLI
0
gnomAD missense Z
0.96
DepMap mean gene effect
0.14
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

Biological processes

Molecular functions

Cellular components

Protein domainsUniProt · Pfam · InterPro

KeywordsUniProt

Antibody and autoantibody relevanceSeroatlas analysis

Seroatlas reads CCR9 as an antibody target. Whether an autoantibody or antibody against CCR9 could matter depends on whether native CCR9 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

CCR9 is annotated at the cell surface, where native CCR9 is exposed to circulating antibodies and is a prime autoantibody target that could block, deplete, or overstimulate it.

Annotation status

The present source text does not explicitly label CCR9 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/CCR9. 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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