Prestin, a member of the SLC26 family of anion transporters, generates the fast voltage-driven motility of mammalian outer hair cells. Conformational reorientation of the molecule is driven by the transmembrane movement of electrical charge, possibly monovalent anions. Charge translocation corresponds to a voltage-dependent non-linear capacitance (NLC). Recently, homologues of Prestin were identified from zebrafish ('zPres') and drosophila. The zebrafish SLC26 member is the closest homologue of mammalian prestin known so far. We have analyzed the electrophysiological properties of zPres transfected transiently into CHO cells. In cells expressing zPres-GFP, voltage jumps elicited capacitive currents, resembling the voltage dependent charge movement of mammalian prestin. Charge transfer could be reasonably described by a 2-state Boltzmann function; however voltage dependence was more shallow and voltage at half-maximum charge transfer was more positive than for mammalian prestin. Kinetics of charge transfer were voltage dependent and slower than with mammalian prestin. Moreover, zPres generated NLC with properties corresponding to those of the charge transfer. The similarity to mammalian prestin suggests that prestin-driven electromotility may have evolved from anion transport and may be mechanistically related to a transport cycle. (Supported by EC FP6 funding, contract no.512063, EuroHear)