The Evolution of Prestin: Examination with Membrane Thickness Sensitivity

摘要

Prestin (SLC26A5) is a membrane protein that is essential for electromotility of outer hair cells and, in turn, for the cochlear amplifier. This function is mammalian innovation and prestin orthologs in non-mammalian hair cells function as anion exchangers rather than a motile element. Taking advantage of this evolutionary change, we found that the sensitivity of prestin orthologs to membrane thickness is inversely related to their effectiveness for the motile function. In addition, a chimera between zebrafish prestin and rat prestin, which shows motile functionality, has membrane thickness sensitivity lower than any prestin ortholog we have examined, confirming the relationship.