Seroatlas · Human Serome Atlas

GJA8

Gap junction alpha-8 protein

Also known as: CAE, CAE1, CX50, CXA8_HUMAN, CZP1

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

Protein identityUniProt · HPA

UniProt accession
P48165
Gene
GJA8
Ensembl
ENSG00000121634
Chromosome
1
Canonical length
433 aa
Protein class
Disease related genes, Human disease related genes, Potential drug targets, Predicted membrane proteins, Transporters

OverviewNCBI Gene

This gene encodes a transmembrane connexin protein that is necessary for lens growth and maturation of lens fiber cells. The encoded protein is a component of gap junction channels and functions in a calcium and pH-dependent manner. Mutations in this gene have been associated with zonular pulverulent cataracts, nuclear progressive cataracts, and cataract-microcornea syndrome. [provided by RefSeq, Dec 2009]

Canonical amino-acid sequenceUniProt

433 residues, UniProt reviewed canonical sequence.

>P48165|GJA8
     1  MGDWSFLGNI LEEVNEHSTV IGRVWLTVLF IFRILILGTA AEFVWGDEQS DFVCNTQQPG
    61  CENVCYDEAF PISHIRLWVL QIIFVSTPSL MYVGHAVHYV RMEEKRKSRE AEELGQQAGT
   121  NGGPDQGSVK KSSGSKGTKK FRLEGTLLRT YICHIIFKTL FEVGFIVGHY FLYGFRILPL
   181  YRCSRWPCPN VVDCFVSRPT EKTIFILFML SVASVSLFLN VMELGHLGLK GIRSALKRPV
   241  EQPLGEIPEK SLHSIAVSSI QKAKGYQLLE EEKIVSHYFP LTEVGMVETS PLPAKPFNQF
   301  EEKISTGPLG DLSRGYQETL PSYAQVGAQE VEGEGPPAEE GAEPEVGEKK EEAERLTTEE
   361  QEKVAVPEGE KVETPGVDKE GEKEEPQSEK VSKQGLPAEK TPSLCPELTT DDARPLSRLS
   421  KASSRARSDD LTV

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against GJA8 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)
0.53
Highest tissue expression
5.5 nTPM

Expression across tissuesHPA

Tissue

  • testis: 5.5 nTPM
  • kidney: 0.1 nTPM
  • adipose tissue: 0 nTPM
  • adrenal gland: 0 nTPM
  • amygdala: 0 nTPM
  • appendix: 0 nTPM

Single-cell type

  • late primary spermatocytes: 83 nCPM
  • late spermatids: 9 nCPM
  • early spermatids: 7.3 nCPM
  • distal convoluted tubule cells: 1.4 nCPM
  • loop of henle epithelial cells: 1.1 nCPM
  • renal collecting duct principal cells: 0.8 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

  • cerebral cortex: 0.2 nTPM
  • pons: 0.1 nTPM
  • amygdala: 0 nTPM
  • basal ganglia: 0 nTPM
  • cerebellum: 0 nTPM
  • choroid plexus: 0 nTPM

DiseaseUniProt · ClinVar · IEDB · PubMed

Four sources answering four different questions about GJA8.

Disease | AllUniProt

Conditions GJA8 is implicated in, by any mechanism.

Disease | GeneticClinVar

53 pathogenic / likely-pathogenic of 303 ClinVar records.

Conditions with pathogenic or likely-pathogenic variants.

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
gnomAD pLI
0
gnomAD missense Z
-0.2
DepMap mean gene effect
-0.05
DepMap dependency class
selective

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 GJA8 as an antibody target. Whether an autoantibody or antibody against GJA8 could matter depends on whether native GJA8 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

GJA8 is annotated at the cell surface, where native GJA8 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 GJA8 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/GJA8. 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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