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Aliases for GJA8 Gene

Aliases for GJA8 Gene

  • Gap Junction Protein, Alpha 8, 50kDa 2 3
  • CX50 3 4 6
  • Lens Fiber Protein MP70 3 4
  • Connexin 50 2 3
  • Connexin-50 3 4
  • CTRCT1 3 6
  • CAE1 3 6
  • CZP1 3 6
  • Gap Junction Protein, Alpha 8, 50kDa (Connexin 50) 2
  • Gap Junction Protein, Alpha 8, 50kD (Connexin 50) 2
  • Gap Junction Membrane Channel Protein Alpha-8 3
  • Lens Intrinsic Membrane Protein MP70 3
  • Gap Junction Protein Alpha 8 50kDa 3
  • Gap Junction Alpha-8 Protein 3
  • Cell Surface Glycoprotein 3
  • MP70 3
  • CAE 3

External Ids for GJA8 Gene

Previous HGNC Symbols for GJA8 Gene

  • CAE1
  • CZP1
  • CAE

Previous GeneCards Identifiers for GJA8 Gene

  • GC01P145594
  • GC01P144100
  • GC01P144718
  • GC01P144882
  • GC01P144599
  • GC01P145841
  • GC01P147374
  • GC01P120788

Summaries for GJA8 Gene

Entrez Gene Summary for GJA8 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]

GeneCards Summary for GJA8 Gene

GJA8 (Gap Junction Protein, Alpha 8, 50kDa) is a Protein Coding gene. Diseases associated with GJA8 include cataract 1, multiple types and cataract microcornea syndrome. Among its related pathways are Clathrin derived vesicle budding and Myometrial Relaxation and Contraction Pathways. GO annotations related to this gene include channel activity. An important paralog of this gene is GJB3.

UniProtKB/Swiss-Prot for GJA8 Gene

  • One gap junction consists of a cluster of closely packed pairs of transmembrane channels, the connexons, through which materials of low MW diffuse from one cell to a neighboring cell

Tocris Summary for GJA8 Gene

  • Gap channels (also known as gap junctions) are specalized cell-cell contacts between almost all eukaryotic cells that provide direct intracellular communication. Generally, gap channels allow the passive diffusion of molecules up to 1 kDa which includes nutrients, small metabolites (e.g. glucose), ions (K+, Ca2+) and second messengers (IP3, cAMP and cGMP). Gap channels allow electrical and biochemical coupling between cells and in excitable tissues, such as neurons and the heart, enables the generation of synchronized and rapid responses. Structurally, gap channels are composed of two hemichannels called 'connexons', which themselves are formed from six connexin molecules. Homo- and heteromeric combinations are seen, which exhibit distinct permeability, selectivity and functional properties. Pannexins are related to connexins and can also form gap junctions. However, their expression is limited to the brain. Furthermore, in nonchordate animals a family of proteins called innexins form these channels. Gap channels are regulated through post-translational modifications of the C'-terminal cytoplasmic tail and phosphorylation modulates assembly and their physiological properties. They are continuously synthesized and degraded, allowing tissues to rapidly adapt to changing environmental conditions. Connexins play a key role in many physiological processes including cardiac and smooth muscle contraction, regulation of neuronal excitability, epithelial electrolyte transport and keratinocyte differentiation. Mutations in connexin genes are associated with human diseases including sensorineural deafness, a variety of skin disorders, peripheral neuropathy and cardiovascular disease.

Gene Wiki entry for GJA8 Gene

No data available for PharmGKB "VIP" Summary , fRNAdb sequence ontologies and piRNA Summary for GJA8 Gene

Genomics for GJA8 Gene

Regulatory Elements for GJA8 Gene

Genomic Location for GJA8 Gene

147,902,820 bp from pter
147,909,269 bp from pter
6,450 bases
Plus strand

Genomic View for GJA8 Gene

UCSC Golden Path with GeneCards custom track
Cytogenetic band:
Genomic Location for GJA8 Gene
GeneLoc Logo Genomic Neighborhood Exon StructureGene Density

RefSeq DNA sequence for GJA8 Gene

Proteins for GJA8 Gene

  • Protein details for GJA8 Gene (UniProtKB/Swiss-Prot)

    Protein Symbol:
    Recommended name:
    Gap junction alpha-8 protein
    Protein Accession:
    Secondary Accessions:
    • A7L5M5
    • Q5VVN9
    • Q9NP25

    Protein attributes for GJA8 Gene

    433 amino acids
    Molecular mass:
    48229 Da
    Quaternary structure:
    • A connexon is composed of a hexamer of connexins. This particular connexin only forms junctional channels

neXtProt entry for GJA8 Gene

Proteomics data for GJA8 Gene at MOPED

Post-translational modifications for GJA8 Gene

  • Modification sites at PhosphoSitePlus
  • Modification sites at neXtProt

Other Protein References for GJA8 Gene

ENSEMBL proteins:
Reactome Protein details:
REFSEQ proteins:

No data available for DME Specific Peptides for GJA8 Gene

Domains for GJA8 Gene

Gene Families for GJA8 Gene

  • GJ :Ion channels / Gap junction proteins (connexins)

Suggested Antigen Peptide Sequences for GJA8 Gene

GenScript: Design optimal peptide antigens:

Graphical View of Domain Structure for InterPro Entry



  • P48165
  • Belongs to the connexin family. Alpha-type (group II) subfamily.
genes like me logo Genes that share domains with GJA8: view

Function for GJA8 Gene

Molecular function for GJA8 Gene

GENATLAS Biochemistry: gap junction protein alpha 8,50kDa,connexin 50 (MP70),expressed in lens,monomer of the connexon (six subunits including GJA3,GJA8,GJB1,GJB2)
UniProtKB/Swiss-Prot Function: One gap junction consists of a cluster of closely packed pairs of transmembrane channels, the connexons, through which materials of low MW diffuse from one cell to a neighboring cell

Gene Ontology (GO) - Molecular Function for GJA8 Gene

GO ID Qualified GO term Evidence PubMed IDs
GO:0005243 gap junction channel activity IEA --
GO:0005515 protein binding --
GO:0015267 channel activity TAS 7796604
genes like me logo Genes that share ontologies with GJA8: view
genes like me logo Genes that share phenotypes with GJA8: view

Animal Models for GJA8 Gene

MGI Knock Outs for GJA8:

Animal Model Products

miRNA for GJA8 Gene

miRTarBase miRNAs that target GJA8

miRNA Products

Inhibitory RNA Products

  • Predesigned siRNA for gene silencing in human,mouse,rat for GJA8

In Situ Assay Products

Flow Cytometry Products

No data available for Enzyme Numbers (IUBMB) , Transcription Factor Targeting and HOMER Transcription for GJA8 Gene

Localization for GJA8 Gene

Subcellular locations from UniProtKB/Swiss-Prot for GJA8 Gene

Cell membrane; Multi-pass membrane protein. Cell junction, gap junction.

Subcellular locations from

Jensen Localization Image for GJA8 Gene COMPARTMENTS Subcellular localization image for GJA8 gene
Compartment Confidence
plasma membrane 5
nucleus 2

Gene Ontology (GO) - Cellular Components for GJA8 Gene

GO ID Qualified GO term Evidence PubMed IDs
GO:0005886 plasma membrane --
GO:0005887 integral component of plasma membrane TAS 7796604
GO:0005922 connexon complex IEA --
GO:0016021 integral component of membrane --
genes like me logo Genes that share ontologies with GJA8: view

Pathways for GJA8 Gene

genes like me logo Genes that share pathways with GJA8: view

Pathways by source for GJA8 Gene

1 Qiagen pathway for GJA8 Gene
1 BioSystems pathway for GJA8 Gene
1 GeneGo (Thomson Reuters) pathway for GJA8 Gene

PCR Array Products

  • Pathway & Disease-focused RT² Profiler PCR Arrays

Interacting Proteins for GJA8 Gene

Selected Interacting proteins: P48165-CXA8_HUMAN for GJA8 Gene via I2D

Gene Ontology (GO) - Biological Process for GJA8 Gene

GO ID Qualified GO term Evidence PubMed IDs
GO:0002088 lens development in camera-type eye IEA --
GO:0006810 transport TAS 7796604
GO:0007154 cell communication --
GO:0007267 cell-cell signaling IEA --
GO:0007601 visual perception TAS 9497259
genes like me logo Genes that share ontologies with GJA8: view

Compounds for GJA8 Gene

(5) Tocris Compounds for GJA8 Gene

Compound Action Cas Number
10Panx Panx-1 mimetic inhibitory peptide; blocks pannexin-1 gap junctions [955091-53-9]
Carbenoxolone disodium Gap junction blocker. Also inhibitor of 11 beta-hydroxysteroid dehydrogenase [7421-40-1]
Gap 26 Gap junction blocker; inhibits smooth muscle contraction and IP3-mediated ATP release [197250-15-0]
Gap 27 Selective gap junction blocker [198284-64-9]
Scrambled 10Panx Scrambled version of 10Panx (Cat. No. 3348), Panx-1 mimetic inhibitory peptide [1315378-72-3]

(4) IUPHAR Ligand for GJA8 Gene

Ligand Type Action Affinity Pubmed IDs
flufenamic acid Channel blocker None
octanol Inhibitor None
Ca2+ Antagonist Antagonist
carbenoxolone Inhibitor None

(4) Novoseek inferred chemical compound relationships for GJA8 Gene

Compound -log(P) Hits PubMed IDs
isofenphos 84.6 1
valine 33.7 2
serine 26.1 2
proline 25.4 1
genes like me logo Genes that share compounds with GJA8: view

Transcripts for GJA8 Gene

mRNA/cDNA for GJA8 Gene

(7) Selected AceView cDNA sequences:
(3) REFSEQ mRNAs :
(0) Additional mRNA sequences :
(1) Ensembl transcripts including schematic representations, and UCSC links where relevant :

Unigene Clusters for GJA8 Gene

Gap junction protein, alpha 8, 50kDa:
Representative Sequences:

miRNA Products

Inhibitory RNA Products

  • Predesigned siRNA for gene silencing in human,mouse,rat for GJA8

Primer Products

  • OriGene qSTAR qPCR primer pairs in human,mouse,rat for GJA8
  • QuantiTect SYBR Green Assays in human,mouse,rat
  • Pre-validated RT² qPCR Primer Assay in human,mouse,rat
  • QuantiFast Probe-based Assays in human,mouse,rat

Flow Cytometry Products

Alternative Splicing Database (ASD) splice patterns (SP) for GJA8 Gene

No ASD Table

Relevant External Links for GJA8 Gene

GeneLoc Exon Structure for
ECgene alternative splicing isoforms for

Expression for GJA8 Gene

mRNA expression in normal human tissues for GJA8 Gene

mRNA differential expression in normal tissues according to GTEx for GJA8 Gene

This gene is overexpressed in Testis (51.1).

Integrated Proteomics: protein expression from ProteomicsDB and MOPED for GJA8 Gene

SOURCE GeneReport for Unigene cluster for GJA8 Gene Hs.632441

mRNA Expression by UniProt/SwissProt for GJA8 Gene

Tissue specificity: Eye lens
genes like me logo Genes that share expressions with GJA8: view

In Situ Assay Products

Orthologs for GJA8 Gene

This gene was present in the common ancestor of chordates.

Orthologs for GJA8 Gene

Organism Taxonomy Gene Similarity Type Details
(Pan troglodytes)
Mammalia GJA8 35
  • 99.62 (n)
  • 99.31 (a)
GJA8 36
  • 99 (a)
(Bos Taurus)
Mammalia GJA8 35
  • 86.68 (n)
  • 86.61 (a)
GJA8 36
  • 86 (a)
(Canis familiaris)
Mammalia GJA8 35
  • 88.43 (n)
  • 89.12 (a)
GJA8 36
  • 88 (a)
(Mus musculus)
Mammalia Gja8 35
  • 85.6 (n)
  • 88.68 (a)
Gja8 16
Gja8 36
  • 87 (a)
(Monodelphis domestica)
Mammalia GJA8 36
  • 85 (a)
(Ornithorhynchus anatinus)
Mammalia GJA8 36
  • 85 (a)
(Rattus norvegicus)
Mammalia Gja8 35
  • 86.07 (n)
  • 88.22 (a)
(Gallus gallus)
Aves GJA8 35
  • 73.16 (n)
  • 76.71 (a)
GJA8 36
  • 73 (a)
(Anolis carolinensis)
Reptilia GJA8 36
  • 68 (a)
African clawed frog
(Xenopus laevis)
Amphibia Xl.23631 35
tropical clawed frog
(Silurana tropicalis)
Amphibia gja8 35
  • 65 (n)
  • 68.17 (a)
(Danio rerio)
Actinopterygii cx44.1 35
  • 70.61 (n)
  • 73.68 (a)
cx44.1 36
  • 69 (a)
cx50.5 36
  • 38 (a)
Species with no ortholog for GJA8:
  • A. gosspyii yeast (Ashbya gossypii)
  • Actinobacteria (Mycobacterium tuberculosis)
  • African malaria mosquito (Anopheles gambiae)
  • Alicante grape (Vitis vinifera)
  • alpha proteobacteria (Wolbachia pipientis)
  • amoeba (Dictyostelium discoideum)
  • Archea (Pyrococcus horikoshii)
  • baker's yeast (Saccharomyces cerevisiae)
  • barley (Hordeum vulgare)
  • beta proteobacteria (Neisseria meningitidis)
  • bread mold (Neurospora crassa)
  • Chromalveolata (Phytophthora infestans)
  • common water flea (Daphnia pulex)
  • corn (Zea mays)
  • E. coli (Escherichia coli)
  • filamentous fungi (Aspergillus nidulans)
  • Firmicute bacteria (Streptococcus pneumoniae)
  • fission yeast (Schizosaccharomyces pombe)
  • fruit fly (Drosophila melanogaster)
  • green algae (Chlamydomonas reinhardtii)
  • honey bee (Apis mellifera)
  • K. lactis yeast (Kluyveromyces lactis)
  • loblloly pine (Pinus taeda)
  • malaria parasite (Plasmodium falciparum)
  • medicago trunc (Medicago Truncatula)
  • moss (Physcomitrella patens)
  • orangutan (Pongo pygmaeus)
  • pig (Sus scrofa)
  • rainbow trout (Oncorhynchus mykiss)
  • rice (Oryza sativa)
  • rice blast fungus (Magnaporthe grisea)
  • schistosome parasite (Schistosoma mansoni)
  • sea anemone (Nematostella vectensis)
  • sea squirt (Ciona intestinalis)
  • sea squirt (Ciona savignyi)
  • sea urchin (Strongylocentrotus purpuratus)
  • sorghum (Sorghum bicolor)
  • soybean (Glycine max)
  • stem rust fungus (Puccinia graminis)
  • sugarcane (Saccharum officinarum)
  • thale cress (Arabidopsis thaliana)
  • tomato (Lycopersicon esculentum)
  • toxoplasmosis (Toxoplasma gondii)
  • Trichoplax (Trichoplax adhaerens)
  • wheat (Triticum aestivum)
  • worm (Caenorhabditis elegans)

Evolution for GJA8 Gene

Gene Tree for GJA8 (if available)
Gene Tree for GJA8 (if available)

Paralogs for GJA8 Gene

Paralogs for GJA8 Gene

Selected SIMAP similar genes for GJA8 Gene using alignment to 1 proteins:

genes like me logo Genes that share paralogs with GJA8: view

Variants for GJA8 Gene

Sequence variations from dbSNP and Humsavar for GJA8 Gene

SNP ID Clin Chr 01 pos Sequence Context AA Info Type MAF
rs985711 -- 147,907,240(+) AAGTT(A/C)TCACT intron-variant
rs989192 -- 147,903,476(+) TGAAC(A/G)CTTTG intron-variant
rs1495960 -- 147,903,581(+) TCACA(G/T)CCTAG intron-variant
rs1532399 -- 147,909,317(-) CACCT(G/T)TTCCT downstream-variant-500B
rs2101872 -- 147,905,819(+) CCCTC(C/T)CCATT intron-variant

Structural Variations from Database of Genomic Variants (DGV) for GJA8 Gene

Variant ID Type Subtype PubMed ID
nsv7181 OTHER Inversion 18451855
nsv872266 CNV Gain 21882294
nsv463517 CNV Gain 19166990
nsv831437 CNV Loss 17160897

Relevant External Links for GJA8 Gene

HapMap Linkage Disequilibrium report
Human Gene Mutation Database (HGMD)
Locus Specific Mutation Databases (LSDB)

No data available for Polymorphic Variants from UniProtKB/Swiss-Prot for GJA8 Gene

Disorders for GJA8 Gene

(1) OMIM Diseases for GJA8 Gene (600897)


  • Cataract 1, multiple types (CTRCT1) [MIM:116200]: An opacification of the crystalline lens of the eye that frequently results in visual impairment or blindness. Opacities vary in morphology, are often confined to a portion of the lens, and may be static or progressive. CTRCT1 includes congenital, zonular pulverulent, nuclear progressive, nuclear pulverulent, nuclear total, total, and posterior subcapsular types of cataract. Zonular or lamellar cataracts are opacities, broad or narrow, usually consisting of powdery white dots affecting only certain layers or zones between the cortex and nucleus of an otherwise clear lens. The opacity may be so dense as to render the entire central region of the lens completely opaque, or so translucent that vision is hardly if at all impeded. Zonular cataracts generally do not involve the embryonic nucleus, though sometimes they involve the fetal nucleus. Usually sharply separated from a clear cortex outside them, they may have projections from their outer edges known as riders or spokes. In some cases cataract is associated with microcornea without any other systemic anomaly or dysmorphism. Microcornea is defined by a corneal diameter inferior to 10 mm in both meridians in an otherwise normal eye. {ECO:0000269 PubMed:10480374, ECO:0000269 PubMed:11846744, ECO:0000269 PubMed:14627691, ECO:0000269 PubMed:16234473, ECO:0000269 PubMed:16604058, ECO:0000269 PubMed:18006672, ECO:0000269 PubMed:21174522, ECO:0000269 PubMed:21921990, ECO:0000269 PubMed:23508780, ECO:0000269 PubMed:9497259, ECO:0000269 Ref.4}. Note=The disease is caused by mutations affecting the gene represented in this entry.

(2) University of Copenhagen DISEASES for GJA8 Gene

(6) Novoseek inferred disease relationships for GJA8 Gene

Disease -log(P) Hits PubMed IDs
pulverulent zonular cataract 94.9 3
cataract, autosomal dominant 85.4 1
congenital cataract 83.8 4
cataract 70.6 20
nuclear cataract 65.4 2

Relevant External Links for GJA8

Genetic Association Database (GAD)
Human Genome Epidemiology (HuGE) Navigator
genes like me logo Genes that share disorders with GJA8: view

Publications for GJA8 Gene

  1. The human lens intrinsic membrane protein MP70 (Cx50) gene: clonal analysis and chromosome mapping. (PMID: 7796604) Church R.L. … Steele E. (Curr. Eye Res. 1995) 2 3 4 23
  2. A missense mutation in the human connexin50 gene (GJA8) underlies autosomal dominant 'zonular pulverulent' cataract, on chromosome 1q. (PMID: 9497259) Shiels A. … Bhattacharya S. (Am. J. Hum. Genet. 1998) 2 3 4 23
  3. The human lens intrinsic membrane protein MP70 (Cx50) gene: clonal analysis and chromosome mapping. (PMID: 8549164) Church R.L. … Steele E. (Curr. Eye Res. 1995) 3 4 23
  4. Connexin 50 gene on human chromosome 1q21 is associated with schizophrenia in matched case control and family-based studies. (PMID: 17412882) Ni X. … Kennedy J.L. (J. Med. Genet. 2007) 3 23 48
  5. A novel connexin50 mutation associated with congenital nuclear pulverulent cataracts. (PMID: 18006672) Arora A. … Moore A.T. (J. Med. Genet. 2008) 3 4 23

Products for GJA8 Gene

  • Pathway & Disease-focused RT² Profiler PCR Arrays
  • QIAGEN qRT-PCR Assays for microRNAs that regulate GJA8
    • QuantiTect SYBR Green Assays in human,mouse,rat
    • Pre-validated RT² qPCR Primer Assay in human,mouse,rat
    • QuantiFast Probe-based Assays in human,mouse,rat
    • Predesigned siRNA for gene silencing in human,mouse,rat for GJA8
    • Block miRNA regulation of GJA8 using miScript Target Protectors

    Sources for GJA8 Gene

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