Seroatlas · Human Serome Atlas

GJA5

Gap junction alpha-5 protein

Also known as: CX40, CXA5_HUMAN

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

Protein identityUniProt · HPA

UniProt accession
P36382
Gene
GJA5
Ensembl
ENSG00000265107
Chromosome
1
Canonical length
358 aa
Protein class
Disease related genes, Human disease related genes, Potential drug targets, Predicted membrane proteins, Transporters

OverviewNCBI Gene

This gene is a member of the connexin gene family. The encoded protein is a component of gap junctions, which are composed of arrays of intercellular channels that provide a route for the diffusion of low molecular weight materials from cell to cell. Mutations in this gene may be associated with atrial fibrillation. Alternatively spliced transcript variants encoding the same isoform have been described. [provided by RefSeq, Jul 2008]

Canonical amino-acid sequenceUniProt

358 residues, UniProt reviewed canonical sequence.

>P36382|GJA5
     1  MGDWSFLGNF LEEVHKHSTV VGKVWLTVLF IFRMLVLGTA AESSWGDEQA DFRCDTIQPG
    61  CQNVCYDQAF PISHIRYWVL QIIFVSTPSL VYMGHAMHTV RMQEKRKLRE AERAKEVRGS
   121  GSYEYPVAEK AELSCWEEGN GRIALQGTLL NTYVCSILIR TTMEVGFIVG QYFIYGIFLT
   181  TLHVCRRSPC PHPVNCYVSR PTEKNVFIVF MLAVAALSLL LSLAELYHLG WKKIRQRFVK
   241  PRQHMAKCQL SGPSVGIVQS CTPPPDFNQC LENGPGGKFF NPFSNNMASQ QNTDNLVTEQ
   301  VRGQEQTPGE GFIQVRYGQK PEVPNGVSPG HRLPHGYHSD KRRLSKASSK ARSDDLSV

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against GJA5 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
4
Mean surface accessibility (rSASA)
0.47
Highest tissue expression
80 nTPM

Expression across tissuesHPA

Tissue

  • placenta: 80 nTPM
  • heart muscle: 34 nTPM
  • lung: 25 nTPM
  • blood vessel: 24 nTPM
  • adipose tissue: 17 nTPM
  • kidney: 16 nTPM

Single-cell type

  • extravillous trophoblasts: 456 nCPM
  • migrating cytotrophoblasts: 210 nCPM
  • cytotrophoblasts: 160 nCPM
  • vascular endothelial cells: 39 nCPM
  • vascular smooth muscle cells: 24 nCPM
  • syncytiotrophoblasts: 23 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

  • basal ganglia: 3.6 nTPM
  • medulla oblongata: 2.6 nTPM
  • thalamus: 2.6 nTPM
  • cerebral cortex: 2.3 nTPM
  • white matter: 2.3 nTPM
  • pons: 2.2 nTPM

DiseaseUniProt · ClinVar · IEDB · PubMed

Four sources answering four different questions about GJA5.

Disease | AllUniProt

Conditions GJA5 is implicated in, by any mechanism.

Disease | GeneticClinVar

7 pathogenic / likely-pathogenic of 347 ClinVar records.

Conditions with pathogenic or likely-pathogenic variants.

  • Atrial fibrillation, familial, 11
  • Atrial standstill 1
  • Atrial fibrillation, somatic

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)
0.81
gnomAD pLI
0.02
gnomAD missense Z
1.11
DepMap mean gene effect
-0.13
DepMap dependency class
selective

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

Biological processes

Molecular functions

Cellular components

Protein domainsUniProt · Pfam · InterPro

KeywordsUniProt

Antibody and autoantibody relevanceSeroatlas analysis

Seroatlas reads GJA5 as an antibody target. Whether an autoantibody or antibody against GJA5 could matter depends on whether native GJA5 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

GJA5 is annotated at the cell surface, where native GJA5 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 GJA5 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/GJA5. 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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