Voltage does not drive prestin (SLC26a5) electro-mechanical activity at high frequencies where cochlear amplification is best.

Summary Cochlear amplification denotes a boost to auditory sensitivity and selectivity that is dependent on outer hair cells from Corti’s organ. Voltage-driven electromotility of the cell is believed to feed energy back into the cochlear partition via a cycle-by-cycle mechanism at very high acoustic frequencies. Here we show using wide-band macro-patch voltage-clamp to drive prestin, the molecular motor underlying electromotility, that its voltage-sensor charge movement is unusually low pass in nature, being incapable of following high frequency voltage changes. Our data are incompatible with a cycle-by-cycle mechanism responsible for high frequency tuning in mammals.