Seroatlas · Human Serome Atlas

CX3CR1

CX3C chemokine receptor 1

Also known as: CCRL1, CMKBRL1, CMKDR1, CX3C1_HUMAN, GPR13, V28

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

Protein identityUniProt · HPA

UniProt accession
P49238
Gene
CX3CR1
Ensembl
ENSG00000168329
Chromosome
3
Canonical length
355 aa
Protein class
Disease related genes, G-protein coupled receptors, Human disease related genes, Plasma proteins, Potential drug targets, Predicted membrane proteins
Subcellular location
Plasma membrane

OverviewNCBI Gene

Fractalkine is a transmembrane protein and chemokine involved in the adhesion and migration of leukocytes. The protein encoded by this gene is a receptor for fractalkine. The encoded protein also is a coreceptor for HIV-1, and some variations in this gene lead to increased susceptibility to HIV-1 infection and rapid progression to AIDS. Four transcript variants encoding two different isoforms have been found for this gene. [provided by RefSeq, Jan 2010]

Canonical amino-acid sequenceUniProt

355 residues, UniProt reviewed canonical sequence.

>P49238|CX3CR1
     1  MDQFPESVTE NFEYDDLAEA CYIGDIVVFG TVFLSIFYSV IFAIGLVGNL LVVFALTNSK
    61  KPKSVTDIYL LNLALSDLLF VATLPFWTHY LINEKGLHNA MCKFTTAFFF IGFFGSIFFI
   121  TVISIDRYLA IVLAANSMNN RTVQHGVTIS LGVWAAAILV AAPQFMFTKQ KENECLGDYP
   181  EVLQEIWPVL RNVETNFLGF LLPLLIMSYC YFRIIQTLFS CKNHKKAKAI KLILLVVIVF
   241  FLFWTPYNVM IFLETLKLYD FFPSCDMRKD LRLALSVTET VAFSHCCLNP LIYAFAGEKF
   301  RRYLYHLYGK CLAVLCGRSV HVDFSSSESQ RSRHGSVLSS NFTYHTSDGD ALLLL

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against CX3CR1 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)
0.34
Highest tissue expression
33 nTPM

Expression across tissuesHPA

Tissue

  • cerebral cortex: 33 nTPM
  • midbrain: 12 nTPM
  • spleen: 11 nTPM
  • spinal cord: 11 nTPM
  • lung: 9.3 nTPM
  • amygdala: 7.1 nTPM

Single-cell type

  • microglia: 937 nCPM
  • nk-cells: 104 nCPM
  • macrophages: 41 nCPM
  • cdc: 35 nCPM
  • monocytes: 21 nCPM
  • t-cells: 9 nCPM

Immune cell

  • non-classical monocyte: 451 nTPM
  • gdT-cell: 265 nTPM
  • intermediate monocyte: 261 nTPM
  • total PBMC: 233 nTPM
  • memory CD8 T-cell: 145 nTPM
  • naive CD8 T-cell: 123 nTPM

Brain region

  • white matter: 63 nTPM
  • spinal cord: 52 nTPM
  • medulla oblongata: 47 nTPM
  • thalamus: 43 nTPM
  • pons: 40 nTPM
  • midbrain: 33 nTPM

DiseaseUniProt · ClinVar · IEDB · PubMed

Four sources answering four different questions about CX3CR1.

Disease | AllUniProt

Conditions CX3CR1 is implicated in, by any mechanism.

  • Macular degeneration, age-related, 12 (ARMD12) MIM:613784

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)
1.01
gnomAD pLI
0.06
gnomAD missense Z
1.08
DepMap mean gene effect
0.03
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 CX3CR1 as an antibody target. Whether an autoantibody or antibody against CX3CR1 could matter depends on whether native CX3CR1 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

CX3CR1 is annotated at the cell surface, where native CX3CR1 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 CX3CR1 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/CX3CR1. 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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