GJA8

Protein-coding gene in the species Homo sapiens

GJA8

Identifiers

Aliases

GJA8, CAE, CAE1, CTRCT1, CX50, CZP1, MP70, gap junction protein alpha 8

External IDs

OMIM: 600897 MGI: 99953 HomoloGene: 3857 GeneCards: GJA8

Gene location (Human)

Chr.	Chromosome 1 (human)^[1]

Band	1q21.2	Start	147,902,795 bp^[1]
Band	1q21.2	End	147,909,269 bp^[1]

Gene location (Mouse)

Chr.	Chromosome 3 (mouse)^[2]

Band	3 F2.1\|3	Start	96,820,882 bp^[2]
Band	3 F2.1\|3	End	96,833,336 bp^[2]

RNA expression pattern

Bgee

Human

Mouse (ortholog)

Top expressed in

muscle tissue

kidney

kidney

connective tissue

smooth muscle tissue

adipose tissue

right lobe of liver

viscus

spleen

abdominal fat

Top expressed in

lens

sternocleidomastoid muscle

More reference expression data

BioGPS


More reference expression data

Gene ontology
Molecular function	channel activity gap junction channel activity
Cellular component	integral component of membrane gap junction cell junction plasma membrane integral component of plasma membrane connexin complex membrane
Biological process	cell communication cell-cell signaling camera-type eye development lens development in camera-type eye protein homooligomerization transmembrane transport visual perception gap junction-mediated intercellular transport
Sources:Amigo / QuickGO

Orthologs

Species

Human

Mouse

Entrez


2703


14616

Ensembl


ENSG00000121634


ENSMUSG00000049908

UniProt


P48165


P28236

RefSeq (mRNA)


NM_005267


NM_008123

RefSeq (protein)


NP_005258


NP_032149

Location (UCSC)

Chr 1: 147.9 – 147.91 Mb

Chr 3: 96.82 – 96.83 Mb

PubMed search

^[3]

^[4]

Wikidata

View/Edit Human

View/Edit Mouse

Connexin50

Identifiers

Symbol

Connexin50

Pfam

PF03509

InterPro

IPR002266

Available protein structures:
Pfam	structures / ECOD
PDB	RCSB PDB; PDBe; PDBj
PDBsum	structure summary

Gap junction alpha-8 protein is a protein that in humans is encoded by the GJA8 gene.^[5]^[6]^[7] It is also known as connexin 50.

Interactions

GJA8 has been shown to interact with Tight junction protein 1.^[10]

References

^ ^a ^b ^c GRCh38: Ensembl release 89: ENSG00000121634 – Ensembl, May 2017
^ ^a ^b ^c GRCm38: Ensembl release 89: ENSMUSG00000049908 – Ensembl, May 2017
^ "Human PubMed Reference:". National Center for Biotechnology Information, U.S. National Library of Medicine.
^ "Mouse PubMed Reference:". National Center for Biotechnology Information, U.S. National Library of Medicine.
^ Shiels A, Mackay D, Ionides A, Berry V, Moore A, Bhattacharya S (Apr 1998). "A missense mutation in the human connexin50 gene (GJA8) underlies autosomal dominant "zonular pulverulent" cataract, on chromosome 1q". Am J Hum Genet. 62 (3): 526–32. doi:10.1086/301762. PMC 1376956. PMID 9497259.
^ Church RL, Wang JH, Steele E (Aug 1995). "The human lens intrinsic membrane protein MP70 (Cx50) gene: clonal analysis and chromosome mapping". Curr Eye Res. 14 (3): 215–21. doi:10.3109/02713689509033517. PMID 7796604.
^ "Entrez Gene: GJA8 gap junction protein, alpha 8, 50kDa".
^ ^a ^b Mefford HC, Sharp AJ, Baker C, Itsara A, Jiang Z, Buysse K, Huang S, Maloney VK, Crolla JA, Baralle D, et al. (October 2008). "Recurrent rearrangements of chromosome 1q21.1 and variable pediatric phenotypes". N. Engl. J. Med. 359 (16): 1685–99. doi:10.1056/NEJMoa0805384. PMC 2703742. PMID 18784092.
^ Rong P, Wang X, Niesman I, Wu Y, Benedetti LE, Dunia I, Levy E, Gong X (January 2002). "Disruption of Gja8 (alpha8 connexin) in mice leads to microphthalmia associated with retardation of lens growth and lens fiber maturation". Development. 129 (1): 167–74. doi:10.1242/dev.129.1.167. PMID 11782410.
^ Nielsen PA, Baruch A, Shestopalov VI, Giepmans BN, Dunia I, Benedetti EL, Kumar NM (June 2003). "Lens connexins alpha3Cx46 and alpha8Cx50 interact with zonula occludens protein-1 (ZO-1)". Mol. Biol. Cell. 14 (6): 2470–81. doi:10.1091/mbc.E02-10-0637. PMC 194895. PMID 12808044.

Andrew L Harris; Darren Locke (2009). Connexins, A Guide. New York: Springer. p. 574. ISBN 978-1-934115-46-6.
Cook PJ, Hamerton JL (1980). "Report of the committee on the genetic constitution of chromosome 1". Cytogenet. Cell Genet. 25 (1–4): 9–20. doi:10.1159/000131394. PMID 396131.
Jarvis LJ, Louis CF (1993). "The permeability of reconstituted liposomes containing the purified lens fiber cell integral membrane proteins MP20, MP26 and MP70". J. Membr. Biol. 130 (3): 251–63. doi:10.1007/bf00240482. PMID 1491428. S2CID 2698192.
Church RL, Wang JH, Steele E (1996). "The human lens intrinsic membrane protein MP70 (Cx50) gene: clonal analysis and chromosome mapping". Curr. Eye Res. 14 (10): 979–81. doi:10.3109/02713689508995138. PMID 8549164.
Geyer DD, Church RL, Steele EC, et al. (1998). "Regional mapping of the human MP70 (Cx50; connexin 50) gene by fluorescence in situ hybridization to 1q21.1". Mol. Vis. 3: 13. PMID 9479004.
Dunia I, Recouvreur M, Nicolas P, et al. (1998). "Assembly of connexins and MP26 in lens fiber plasma membranes studied by SDS-fracture immunolabeling". J. Cell Sci. 111 (15): 2109–20. doi:10.1242/jcs.111.15.2109. PMID 9664032.
Hopperstad MG, Srinivas M, Spray DC (2000). "Properties of gap junction channels formed by Cx46 alone and in combination with Cx50". Biophys. J. 79 (4): 1954–66. Bibcode:2000BpJ....79.1954H. doi:10.1016/S0006-3495(00)76444-7. PMC 1301086. PMID 11023900.
Xu X, Berthoud VM, Beyer EC, Ebihara L (2002). "Functional role of the carboxyl terminal domain of human connexin 50 in gap junctional channels". J. Membr. Biol. 186 (2): 101–12. doi:10.1007/s00232-001-0139-5. PMC 2744361. PMID 11944087.
Nielsen PA, Baruch A, Shestopalov VI, et al. (2004). "Lens connexins alpha3Cx46 and alpha8Cx50 interact with zonula occludens protein-1 (ZO-1)". Mol. Biol. Cell. 14 (6): 2470–81. doi:10.1091/mbc.E02-10-0637. PMC 194895. PMID 12808044.
Arora A, Minogue PJ, Liu X, et al. (2006). "A novel GJA8 mutation is associated with autosomal dominant lamellar pulverulent cataract: further evidence for gap junction dysfunction in human cataract". J. Med. Genet. 43 (1): e2. doi:10.1136/jmg.2005.034108. PMC 2564510. PMID 16397066.
Devi RR, Vijayalakshmi P (2006). "Novel mutations in GJA8 associated with autosomal dominant congenital cataract and microcornea". Mol. Vis. 12: 190–5. PMID 16604058.
Zhang X, Zou T, Liu Y, Qi Y (2006). "The gating effect of calmodulin and calcium on the connexin50 hemichannel". Biol. Chem. 387 (5): 595–601. doi:10.1515/BC.2006.076. PMID 16740131. S2CID 25915817.
Ni X, Valente J, Azevedo MH, et al. (2007). "Connexin 50 gene on human chromosome 1q21 is associated with schizophrenia in matched case control and family-based studies". J. Med. Genet. 44 (8): 532–6. doi:10.1136/jmg.2006.047944. PMC 2597930. PMID 17412882.
Kotsias BA, Salim M, Peracchia LL, Peracchia C (2007). "Interplay between cystic fibrosis transmembrane regulator and gap junction channels made of connexins 45, 40, 32 and 50 expressed in oocytes". J. Membr. Biol. 214 (1): 1–8. doi:10.1007/s00232-006-0064-8. PMID 17546509. S2CID 7095255.
Hansen L, Yao W, Eiberg H, et al. (2007). "Genetic heterogeneity in microcornea-cataract: five novel mutations in CRYAA, CRYGD, and GJA8". Invest. Ophthalmol. Vis. Sci. 48 (9): 3937–44. doi:10.1167/iovs.07-0013. PMID 17724170.

Membrane transport protein: ion channels (TC 1A)

Ca²⁺: Calcium channel

Ligand-gated	Inositol trisphosphate receptor 1 2 3 Ryanodine receptor 1 2 3
Voltage-gated	L-type/Ca_vα 1.1 1.2 1.3 1.4 N-type/Ca_vα2.2 P-type/Ca_vα 2.1 Q-type/Ca_vα2.1 R-type/Ca_vα2.3 T-type/Ca_vα 3.1 3.2 3.3 α₂δ-subunits 1 2 β-subunits β1 β2 β3 β4 γ-subunits γ1 γ2 γ3 γ4 Cation channels of sperm 1 2 3 4 Two-pore channel 1 2

Na⁺: Sodium channel

Constitutively active	Epithelial sodium channel α β γ δ
Proton-gated	Amiloride-sensitive cation channel 1 2 3 4
Voltage-gated	Na_vα 1.1 1.2 1.3 1.4 1.5 1.6 1.7 1.8 1.9 7A Na_vβ 1 2 3 4

K⁺: Potassium channel

Calcium-activated	BK channel α1 β1 β2 β3 β4 SK channel SK1 SK2 SK3 IK channel IK1 K_Ca 1.1 2.1 2.2 2.3 3.1 4.1 4.2 5.1
Inward-rectifier	K_ATP K_ir 1.1 2.1 2.2 2.3 2.4 2.6 GIRK/K_ir 3.1 3.2 3.3 3.4 K_ir 4.1 4.2 5.1 6.1 6.2 7.1
Tandem pore domain	K2P 1 2 3 4 5 6 7 9 10 12 13 15 16 17 18
Voltage-gated	K_vα1-6 1.1 1.2 1.3 1.4 1.5 1.6 1.7 1.8 2.1 2.2 3.1 3.2 3.3 3.4 4.1 4.2 4.3 5.1 6.1 6.2 6.3 6.4 K_vα7-12 7.1 7.2 7.3 7.4 7.5 8.1 8.2 9.1 9.2 9.3 10.1 10.2 11.1/hERG 11.2 11.3 12.1 12.2 12.3 K_vβ 1 2 3 KCNIP 1 2 3 4 minK/ISK minK/ISK-like MiRP 1 2 3 Shaker (gene)

Miscellaneous

Cl⁻: Chloride channel	Calcium-activated chloride channels Anoctamin ANO1 Bestrophin 1 2 Chloride Channel Accessory 1 2 3 4 CFTR CLCN 1 2 3 4 5 6 7 KA KB CLIC 1 2 3 4 5 6 L1 CLNS 1A 1B
H⁺: Proton channel	HVCN1
M⁺: CNG cation channel	α 1 2 3 4 β 1 2 3 HCN FC 1 2 3 4
M⁺: TRP cation channel	TRPA (1) TRPC 1 2 3 4 4AP 5 6 7 TRPM 1 2 3 4 5 6 7 8 TRPML 1 2 3 TRPN TRPP 1 2 TRPV 1 2 3 4 5 6
H₂O (+ solutes): Porin	Aquaporin 0 1 2 3 4 5 6 7 8 9 Voltage-dependent anion channel 1 2 3 General bacterial porin family
Cytoplasm: Gap junction	Connexin A GJA1 GJA3 GJA4 GJA5 GJA8 GJA9 GJA10 B GJB1 GJB2 GJB3 GJB4 GJB5 GJB6 GJB7 C GJC1 GJC2 GJC3 D GJD2 GJD3 GJD4 Innexin