KCNK5 channels mostly expressed in cochlear outer sulcus cells are indispensable for hearing

• Published in: Nature communications 2015-11, Vol.6 (1), p.8780-8780, Article 8780
• Main Authors: Cazals, Yves, Bévengut, Michelle, Zanella, Sébastien, Brocard, Frédéric, Barhanin, Jacques, Gestreau, Christian
• Format: Article
• Language: English
• Subjects: 13; 13/51; 14/19; 14/34; 14/63; 631/378/2571; 631/378/2619/1387; 631/378/3917; 631/45/269/1151; 64; 64/110; 9/10; 9/30; Animals; Channels; Cochlea; Cochlea - metabolism; Cochlea - pathology; Cochlea - physiology; Deafness; Deafness - genetics; Deafness - physiopathology; Development Biology; Endolymph - chemistry; Evoked Potentials, Auditory, Brain Stem; Hearing - genetics; Hearing - physiology; Hearing loss; Humanities and Social Sciences; Immunohistochemistry; KCNQ1 Potassium Channel - metabolism; KCNQ1 protein; Life Sciences; Ligaments; Membrane Potentials - genetics; Mice; Mice, Knockout; multidisciplinary; Mutation; Nerve Tissue Proteins - genetics; Neurons and Cognition; Neurosciences; Potassium; Potassium channels; Potassium channels (voltage-gated); Potassium Channels - genetics; Potassium Channels, Inwardly Rectifying - metabolism; Potassium Channels, Tandem Pore Domain - genetics; Round Window, Ear - physiopathology; Science; Science (multidisciplinary); Secretion; Signal transduction; Spiral ganglion; Spiral Ganglion - cytology; Spiral Ganglion - pathology; Stria vascularis; Stria Vascularis - metabolism; Structure-function relationships; Vestibular Function Tests
• ISSN: 2041-1723; 2041-1723
• DOI: 10.1038/ncomms9780

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. Potassium is necessary for the mechanical-electrical transduction needed for hearing. Here the authors study mice lacking the potassium channel KCNK5 and show that these channels are mostly expressed in the outer sulcus and are required for hearing, pointing to their essential role in potassium recycling.