Functional properties of prestin - How the motormolecule works work

Outer hair cells (OHC) of the mammalian cochlea exhibit electromotility that occurs at acoustic frequencies and is thought to produce the amplification of vibrations required for the high sensitivity and frequency selectivity of the mammalian hearing organ. Recent work showed that electromotility is brought about by voltage-driven conformational changes of prestin, a member of the SLC26 family of anion transporters, which is highly expressed in the lateral membrane of the OHC. Prestin binds intracellular anions, predominantly chloride, and uses them as a voltage-sensor. Thus, anions are translocated across the membrane, a process that promotes the structural rearrangements that change the width of prestin in the membrane plane. Accordingly, voltage sensitivity of prestin is strongly affected by the anion species present on the cytoplasmic side as well as by the concentration of the respective anion.