Artículos de revistas
Gap-junctional channel and hemichannel activity of two recently identified connexin 26 mutants associated with deafness
Fecha
2016Registro en:
Pflügers Archiv - European Journal of Physiology, May 2016, vol.468, n°5,p.909-918
Autor
Dalamon, Viviana
Fiori, Mariana
Figueroa, Vania
Oliva, Carolina
Del Río, Rodrigo
González, Wendy
Canan, Jonathan
Elgoyhen, Ana
Altenberg, Guillermo
Retamal, Mauricio
Institución
Resumen
Gap-junction channels (GJCs) are formed by head-to-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.