Click here to close Hello! We notice that you are using Internet Explorer, which is not supported by Xenbase and may cause the site to display incorrectly. We suggest using a current version of Chrome, FireFox, or Safari.
Hum Genet 2004 Aug 01;1153:191-9. doi: 10.1007/s00439-004-1142-6.
Show Gene links Show Anatomy links

Altered gating properties of functional Cx26 mutants associated with recessive non-syndromic hearing loss.

Meşe G , Londin E , Mui R , Brink PR , White TW .

Connexins (Cx) form gap junctions that allow the exchange of small metabolites and ions. In the inner ear, Cx26 is the major gap junction protein and mutations in the Cx26-encoding gene, GJB2, are the most frequent cause of autosomal recessive non-syndromic hearing loss (DFNB1). We have functionally analyzed five Cx26 mutations associated with DFNB1, comprising the following single amino-acid substitutions: T8M, R143W, V153I, N206S and L214P. Coupling of cells expressing wild-type or mutant Cx26 was measured in the paired Xenopus oocyte assay. We found that the R143W, V153I and L214P mutations were unable to form functional channels. In contrast, the T8M and N206S mutants did electrically couple cells, though their voltage gating properties were different from wild-type Cx26 channels. The electrical coupling of oocytes expressing the T8M and N206S mutants suggest that these channels may retain high permeability to potassium ions. Therefore, deafness associated with Cx26 mutations may not only depend on reduced potassium re-circulation in the inner ear. Instead, abnormalities in the exchange of other metabolites through the cochlear gap junction network may also produce deafness.

PubMed ID: 15241677
Article link: Hum Genet
Grant support: [+]

Species referenced: Xenopus
Genes referenced: gjb2
GO keywords: gap junction-mediated intercellular transport

Disease Ontology terms: autosomal dominant nonsyndromic deafness 3A
References [+] :
Barrio, Gap junctions formed by connexins 26 and 32 alone and in combination are differently affected by applied voltage. 1991, Pubmed, Xenbase