GJA8 gap junction protein, alpha 8, 50kDa [Homo sapiens (human)] - Gene

Summary

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Official Symbol: GJA8provided by HGNC
Official Full Name: gap junction protein, alpha 8, 50kDaprovided by HGNC
Primary source: HGNC:4281
See related: Ensembl:ENSG00000121634; HPRD:02939; MIM:600897
Gene type: protein coding
RefSeq status: REVIEWED
Organism: Homo sapiens
Lineage: Eukaryota; Metazoa; Chordata; Craniata; Vertebrata; Euteleostomi; Mammalia; Eutheria; Euarchontoglires; Primates; Haplorrhini; Catarrhini; Hominidae; Homo
Also known as: CAE; CAE1; CX50; CZP1; MP70; CTRCT1
Summary: 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]

Genomic context

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Location :: 1q21.1

Sequence :: Chromosome: 1; NC_000001.10 (147374946..147381396)

See GJA8 in Epigenomics, MapViewer

Chromosome 1 - NC_000001.10 Genomic Context describing neighboring genes

Genomic regions, transcripts, and products

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Genomic Sequence

Go to nucleotideGraphics FASTA GenBank

Go to reference sequence details

Bibliography

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GeneRIFs: Gene References Into Functions What's a GeneRIF?

A PDZ-binding motif and ZO-1 protein are necessary for Cx50 intercellular channel formation
Title: Cx50 requires an intact PDZ-binding motif and ZO-1 for the formation of functional intercellular channels.
A missense D47N mutation in GJA8 is associated with autosomal dominant congenital cataract in a Chinese family.
Title: Another evidence for a D47N mutation in GJA8 associated with autosomal dominant congenital cataract.
Mutations in GJA8 and CRYAA were identified in three Chinese families with cataract and microcornea.
Title: Mutational screening of six genes in Chinese patients with congenital cataract and microcornea.
The G46V and W45S mutations of connexin 50 are in adjacent amino acids. W45S inhibits gap junctional channel function while G46V reduces cell viability by forming open hemichannels.
Title: Different consequences of cataract-associated mutations at adjacent positions in the first extracellular boundary of connexin50.
Autophagy is involoved in the degradation of CX43 and CX50.
Title: Autophagy: a pathway that contributes to connexin degradation.
The genetic mutation in GJA3, GJA8, and LIM2 may slightly contribute to the development of age-related cataracts.
Title: Genetic variations in GJA3, GJA8, LIM2, and age-related cataract in the Chinese population: a mutation screening study.
Two novel nonsynonymous variations and four reported variations in CRYAB, CRYGC, CRYGD, and GJA8, were observed.
Title: Mutation screening and genotype phenotype correlation of α-crystallin, γ-crystallin and GJA8 gene in congenital cataract.
the gap junction protein-alpha 8 polymorphisms may have a role in age-related cataracts
Title: Association between gap junction protein-alpha 8 polymorphisms and age-related cataract.
The D47N mutation of Cx50 causes the hereditary nuclear cataract in this family in an autosomal dominant mode of inheritance with incomplete penetrance.
Title: Genetic linkage analyses and Cx50 mutation detection in a large multiplex Chinese family with hereditary nuclear cataract.
This report is the first to relate p.R198W mutation in GJA8 with congenital cataract-microcornea syndrome.
Title: A novel mutation in GJA8 causing congenital cataract-microcornea syndrome in a Chinese pedigree.

Submit: New GeneRIF Correction See all (30)

Phenotypes

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Find tests for this gene in the NIH Genetic Testing Registry (GTR)

Review eQTL and phenotype association data in this region using PheGenI

Cataract, zonular pulverulent 1

MIM: 116200

Genetic Testing Registry

Interactions

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Products	Interactant	Other Gene	Source	Pubs	Description
P48165	P30301	MIP	HPRD	PubMed
P48165	Q07157	TJP1	HPRD	PubMed
BioGRID:108970	BioGRID:112937	TJP1	BioGRID	PubMed	Affinity Capture-Western; Reconstituted Complex

Pathways from BioSystems

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Calcium Regulation in the Cardiac Cell, organism-specific biosystem (from WikiPathways)
Calcium Regulation in the Cardiac Cell, organism-specific biosystemCalcium is a common signaling mechanism, as once it enters the cytoplasm it exerts allosteric regulatory affects on many enzymes and proteins. Calcium can act in signal transduction after influx resu...
Gap junction assembly, organism-specific biosystem (from REACTOME)
Gap junction assembly, organism-specific biosystemThe assembly of gap junctions involves (1) synthesis of connexin polypeptides at endoplasmic reticulum membranes, (2) oligomerization into homomeric- and heteromeric gap junction connexons (hemi-chan...
Gap junction trafficking, organism-specific biosystem (from REACTOME)
Gap junction trafficking, organism-specific biosystemGap junctions are intercellular communication channels formed from Cx (connexin) protein subunits (see Segretain and Falk 2004 and Evans et al. 2006 for comprehensive reviews). Connexins are transpor...
Gap junction trafficking and regulation, organism-specific biosystem (from REACTOME)
Gap junction trafficking and regulation, organism-specific biosystemGap junctions are clusters of intercellular channels connecting adjacent cells and permitting the direct exchange of ions and small molecules between cells. These channels are composed of two hemicha...
Membrane Trafficking, organism-specific biosystem (from REACTOME)
Membrane Trafficking, organism-specific biosystemThe secretory membrane system allows a cell to regulate delivery of newly synthesized proteins, carbohydrates, and lipids to the cell surface, a necessity for growth and homeostasis. The system is ma...

General gene information

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Markers

NoName (e-PCR)
- UniSTS:489787

NoName (e-PCR)
- UniSTS:480892

GJA8 (e-PCR)
- UniSTS:266367

PMC197251P4 (e-PCR)
- UniSTS:271853

Genotypes

See GJA8 SNP Geneview Report
See GJA8 SNP Genotype Report
See GJA8 SNP Variation Viewer Report

Homology

Homologs of the GJA8 gene: The GJA8 gene is conserved in chimpanzee, Rhesus monkey, dog, cow, mouse, chicken, and zebrafish.
Map Viewer (Mouse)
OrthoDB: The Hierarchical Catalog of Eukaryotic Orthologs

Gene Ontology Provided by GOA

Function	Evidence Code	Pubs
channel activity	TAS Traceable Author Statement more info	PubMed

Process	Evidence Code	Pubs
cell-cell signaling	IEA Inferred from Electronic Annotation more info
lens development in camera-type eye	IEA Inferred from Electronic Annotation more info
protein homooligomerization	IEA Inferred from Electronic Annotation more info
transport	TAS Traceable Author Statement more info	PubMed
visual perception	TAS Traceable Author Statement more info	PubMed

Component	Evidence Code	Pubs
connexon complex	IEA Inferred from Electronic Annotation more info
integral to plasma membrane	TAS Traceable Author Statement more info	PubMed

General protein information

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Preferred Names: gap junction alpha-8 protein

Names: gap junction alpha-8 protein; connexin 50; connexin-50; lens fiber protein MP70; cell surface glycoprotein; lens intrinsic membrane protein MP70; gap junction membrane channel protein alpha-8

NCBI Reference Sequences (RefSeq)

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RefSeqs maintained independently of Annotated Genomes

These reference sequences exist independently of genome builds. Explain

These reference sequences are curated independently of the genome annotation cycle, so their versions may not match the RefSeq versions in the current genome build. Identify version mismatches by comparing the version of the RefSeq in this section to the one reported in Genomic regions, transcripts, and products above.

Genomic

NG_016242.1 RefSeqGene

Range

5001..11451

Download

GenBank, FASTA, Sequence Viewer (Graphics)

mRNA and Protein(s)

NM_005267.4 → NP_005258.2 gap junction alpha-8 protein

Status: REVIEWED

Source sequence(s)

AL445591, BQ184886, CD674975, DB476698

Consensus CDS

CCDS30834.1

UniProtKB/Swiss-Prot

P48165

Related

ENSP00000240986, ENST00000240986

Conserved Domains (3) summary

pfam00029
Location:3 – 109
Blast Score: 607

Connexin; Connexin

pfam03509
Location:260 – 323
Blast Score: 251

Connexin50; Gap junction alpha-8 protein (Cx50)

pfam10582
Location:161 – 227
Blast Score: 339

Connexin_CCC; Gap junction channel protein cysteine-rich domain

RefSeqs of Annotated Genomes: Homo sapiens Annotation Release 104

The following sections contain reference sequences that belong to a specific genome build. Explain

Reference GRCh37.p10 PATCHES

Genomic

NW_003871055.2 Reference GRCh37.p10 PATCHES

Range

4643325..4649774

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GenBank, FASTA, Sequence Viewer (Graphics)

Reference GRCh37.p10 Primary Assembly

Genomic

NC_000001.10 Reference GRCh37.p10 Primary Assembly

Range

147374946..147381396

Download

GenBank, FASTA, Sequence Viewer (Graphics)

Alternate HuRef

Genomic

AC_000133.1 Alternate HuRef

Range

120788421..120794871

Download

GenBank, FASTA, Sequence Viewer (Graphics)

Alternate CHM1_1.0

Genomic

NC_018912.1 Alternate CHM1_1.0

Range

154376277..154382726

Download

GenBank, FASTA, Sequence Viewer (Graphics)

Nucleotide		Protein
Heading	Accession and Version	Protein
genomic	ABBA01004402.1 (235162..241612)	None
genomic	AC239801.3 (108629..115078)	None
genomic	AF217524.1	AAF32309.1
genomic	AL445591.10	CAH72387.1
genomic	AMYH01001373.1 (2512231..2518680)	None
genomic	CH471223.1	EAW50926.1
genomic	U34802.2	AAA77062.1
mRNA	AI364417.1	None
mRNA	BQ184886.1	None
mRNA	CD674975.1	None
mRNA	DB476698.1	None
other-genetic	BC140363.1	AAI40364.1
other-genetic	BC146507.1	AAI46508.1