Gap-junctional channel and hemichannel activity of two recently identified connexin 26 mutants associated with deafness
Gap-junction channels (GJCs) are formed by headto-head association of two hemichannels (HCs, connexin hexamers). HCs and GJCs are permeable to ions and hydrophilic molecules of up to Mr ~1 kDa. Hearing impairment of genetic origin is common, and mutations of connexin 26 (Cx26) are its major cause. W...
| Autores: | , , , , , , , , , |
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| Formato: | artículo |
| Estado: | Versión publicada |
| Fecha de publicación: | 2016 |
| País: | Argentina |
| Recursos: | Consejo Nacional de Investigaciones Científicas y Técnicas |
| Repositorio: | CONICET Digital (CONICET) |
| Idioma: | inglés |
| OAI Identifier: | oai:ri.conicet.gov.ar:11336/44334 |
| Acesso em linha: | http://hdl.handle.net/11336/44334 |
| Access Level: | acceso abierto |
| Palavra-chave: | Deafness Connexins Gap-Junction Channels Mutation https://purl.org/becyt/ford/3.1 https://purl.org/becyt/ford/3 |
| Resumo: | Gap-junction channels (GJCs) are formed by headto-head association of two hemichannels (HCs, connexin hexamers). HCs and GJCs are permeable to ions and hydrophilic molecules of up to Mr ~1 kDa. Hearing impairment of genetic origin is common, and mutations of connexin 26 (Cx26) are its major cause. We recently identified two novel Cx26 mutations in hearing-impaired subjects, L10P and G109V. L10P forms functional GJCs with slightly altered voltage dependence and HCs with decrease ATP/cationic dye selectivity. G109V does not form functional GJCs, but forms functional HCs with enhanced extracellular Ca2+ sensitivity and subtle alterations in voltage dependence and ATP/ cationic dye selectivity. Deafness associated with G109V could result from decreased GJCs activity, whereas deafness associated to L10P may have a more complex mechanism that involves changes in HC permeability. |
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