PUBLICATION

From Zebrafish to Mammal: Functional Evolution of Prestin, the Motor Protein of Cochlear Outer Hair Cells

Authors
Tan, X., Pecka, J.L., Tang, J., Okoruwa, O.E., Zhang, Q., Beisel, K.W., and He, D.Z.
ID
ZDB-PUB-101108-30
Date
2011
Source
Journal of neurophysiology   105(1): 36-44 (Journal)
Registered Authors
Keywords
prestin, motility, outer hair cells, evolution, transporter
MeSH Terms
  • Cell Movement/physiology
  • Hair Cells, Auditory, Outer/physiology*
  • Antiporters/physiology
  • Zebrafish Proteins/physiology*
  • Humans
  • CHO Cells
  • Biological Evolution*
  • Cricetinae
  • Female
  • Gerbillinae
  • Animals
  • Kidney/cytology
  • Kidney/physiology
  • Zebrafish
  • Cricetulus
  • Motor Activity/physiology*
  • Chickens
  • Ovary/cytology
  • Ovary/physiology
  • Anion Transport Proteins/physiology*
  • Cells, Cultured
PubMed
21047933 Full text @ J. Neurophysiol.
Abstract
Prestin is the motor protein of cochlear outer hair cells. It belongs to a distinct anion transporter family called solute carrier protein 26A, or SLC26A. Members of this family serve two fundamentally distinct functions. While most members transport different anion substrates across a variety of epithelia, prestin (SLC26A5) is unique, functioning as a voltage-dependent motor protein. Recent evidence suggests that prestin orthologs from zebrafish and chicken are electrogenic divalent/chloride anion exchangers/transporters with no motor function. These studies appear to suggest that prestin was evolved from an anion transporter. We examined the motor and transport functions of prestin and its orthologs from 4 different species in the vertebrate lineage to gain insights of how these two physiological functions became distinct. Somatic motility, voltage-dependent nonlinear capacitance (NLC) and transporter function were measured in transfected human embryonic kidney (HEK) cells using voltage-clamp and anion uptake techniques. Zebrafish and chicken prestins both exhibited weak NLC with peaks significantly shifted in the depolarization (right) direction. This was contrasted by robust NLC with peaks left shifted in the platypus and gerbil. The platypus and gerbil prestins retained little transporter function in comparison with robust anion transport capacities in the zebrafish and chicken orthologs. Somatic motility was only detected in the platypus and gerbil prestins. There appears to be an inverse relationship between NLC and anion transport functions, whereas motor function appears to have only emerged in mammalian prestin. Our results suggest that motor function is an innovation of therian prestin and is concurrent with diminished transporter capabilities.
Genes / Markers
Figures
Expression
Phenotype
Mutations / Transgenics
Human Disease / Model
Sequence Targeting Reagents
Fish
Antibodies
Orthology
Engineered Foreign Genes
Mapping