Mechanisms of Hair Cell Mechanotransduction Sensitivity Control

Our sense of hearing relies on converting sound vibrations into electrical signals in sensory hair cells. The apically located stereocilia hair bundle is responsible for this conversion of energy through the mechanotransduction process. The regulation of the sensitivity of the mechanotransduction process likely contributes to maximizing the dynamic range of hearing and contributes to the function of the cochlear amplifier. At least two mechanisms can regulate the sensitivity of mechanotransduction. cAMP has been shown to reduced sensitivity of the channel, and we recently described the mechanical changes in the hair bundle leading to the reduction in sensitivity. A second mechanism for sensitivity control is slow adaptation. We recently challenged the prevailing model of slow adaptation and proposed a new model of how slow adaptation functions.