Physiology Commons^™

Mechanotransduction Current Is Essential For Stability Of The Transducing Stereocilia In Mammalian Auditory Hair Cells, A. Catalina Vélez-Ortega, Mary J. Freeman, Artur A. Indzhykulian, Jonathan M. Grossheim, Gregory I. Frolenkov

Physiology Faculty Publications

Mechanotransducer channels at the tips of sensory stereocilia of inner ear hair cells are gated by the tension of 'tip links' interconnecting stereocilia. To ensure maximal sensitivity, tip links are tensioned at rest, resulting in a continuous influx of Ca²⁺ into the cell. Here we show that this constitutive Ca²⁺ influx, usually considered as potentially deleterious for hair cells, is in fact essential for stereocilia stability. In the auditory hair cells of young postnatal mice and rats, a reduction in mechanotransducer current, via pharmacological channel blockers or disruption of tip links, leads to stereocilia shape changes and shortening. …