title: KCNK5 channels mostly expressed in cochlear outer sulcus cells are indispensable for hearing.
abstract: In the cochlea, K(+) is essential for mechano-electrical transduction. Here, we explore cochlear structure and function in mice lacking K(+) channels of the two-pore domain family. A profound deafness associated with a decrease in endocochlear potential is found in adult Kcnk5(-/-) mice. Hearing occurs around postnatal day 19 (P19), and completely disappears 2 days later. At P19, Kcnk5(-/-) mice have a normal endolymphatic [K(+)] but a partly lowered endocochlear potential. Using Lac-Z as a gene reporter, KCNK5 is mainly found in outer sulcus Claudius', Boettcher's and root cells. Low levels of expression are also seen in the spiral ganglion, Reissner's membrane and stria vascularis. Essential channels (KCNJ10 and KCNQ1) contributing to K(+) secretion in stria vascularis have normal expression in Kcnk5(-/-) mice. Thus, KCNK5 channels are indispensable for the maintenance of hearing. Among several plausible mechanisms, we emphasize their role in K(+) recycling along the outer sulcus lateral route.
authors.affiliation: Laboratoire de Neurosciences Intégratives et Adaptatives (UMR7260), Fédération de Recherche 3C (Cerveau, Comportement, Cognition), Aix-Marseille-Université and CNRS, Marseille 13331, France.
authors.forename: Yves
authors.initials: Y
authors.lastname: Cazals
authors.affiliation: Centre de Recherche en Neurobiologie et Neurophysiologie de Marseille (UMR7286), Aix-Marseille-Université and CNRS, Marseille 13344, France.
authors.forename: Michelle
authors.initials: M
authors.lastname: Bévengut
authors.affiliation: Centre de Recherche en Neurobiologie et Neurophysiologie de Marseille (UMR7286), Aix-Marseille-Université and CNRS, Marseille 13344, France.|Institut de Neurosciences de la Timone (UMR7289), Aix-Marseille Université and CNRS, Marseille 13005, France.
authors.forename: Sébastien
authors.initials: S
authors.lastname: Zanella
authors.affiliation: Institut de Neurosciences de la Timone (UMR7289), Aix-Marseille Université and CNRS, Marseille 13005, France.
authors.forename: Frédéric
authors.initials: F
authors.lastname: Brocard
authors.affiliation: Laboratoire de Physio-Médecine Moléculaire (UMR7370), Université de Nice-Sophia Antipolis and CNRS, Nice 06107, France.|Laboratories of Excellence, Ion Channel Science and Therapeutics, France.
authors.forename: Jacques
authors.initials: J
authors.lastname: Barhanin
authors.affiliation: Centre de Recherche en Neurobiologie et Neurophysiologie de Marseille (UMR7286), Aix-Marseille-Université and CNRS, Marseille 13344, France.
authors.forename: Christian
authors.initials: C
authors.lastname: Gestreau
mesh_terms: D000818:Animals; D003051:Cochlea / Q000378:metabolism* / Q000473:pathology / Q000502:physiology; D003638:Deafness / Q000235:genetics* / Q000503:physiopathology; D004710:Endolymph / Q000737:chemistry; D016057:Evoked Potentials, Auditory, Brain Stem; D006309:Hearing / Q000235:genetics* / Q000502:physiology; D007150:Immunohistochemistry; D051657:KCNQ1 Potassium Channel / Q000378:metabolism; D008564:Membrane Potentials / Q000235:genetics; D051379:Mice; D018345:Mice, Knockout; D009154:Mutation; D009419:Nerve Tissue Proteins / Q000235:genetics; D011188:Potassium; D015221:Potassium Channels / Q000235:genetics; D024661:Potassium Channels, Inwardly Rectifying / Q000378:metabolism; D024683:Potassium Channels, Tandem Pore Domain / Q000235:genetics*; D012405:Round Window, Ear / Q000503:physiopathology; D013136:Spiral Ganglion / Q000166:cytology / Q000473:pathology; D013316:Stria Vascularis / Q000378:metabolism; D014724:Vestibular Function Tests; D000098854:Kcnj10 Channel
chemical_list: D051657:KCNQ1 Potassium Channel; D000098854:Kcnj10 Channel; C498739:Kcnk5 protein, mouse; C496910:Kcnq1 protein, mouse; D009419:Nerve Tissue Proteins; D015221:Potassium Channels; D024661:Potassium Channels, Inwardly Rectifying; D024683:Potassium Channels, Tandem Pore Domain; C511784:TASK3 protein, mouse; C420132:potassium channel subfamily K member 3; D011188:Potassium