The transmembrane inner ear (Tmie) protein is essential for normal hearing and balance in the zebrafish.
Little is known about the proteins that mediate mechanoelectrical transduction, the process by which acoustic and accelerational stimuli are transformed by hair cells of the inner ear into electrical signals. In our search for molecules involved in mechanotransduction, we discovered a line of deaf and uncoordinated zebrafish with defective hair-cell function. The hair cells of mutant larvae fail to incorporate fluorophores that normally traverse the transduction channels and their ears lack microphonic potentials in response to vibratory stimuli. Hair cells in the posterior lateral lines of mutants contain numerous lysosomes and have short, disordered hair bundles. Their stereocilia lack two components of the transduction apparatus, tip links and insertional plaques. Positional cloning revealed an early frameshift mutation in tmie, the zebrafish ortholog of the mammalian gene transmembrane inner ear. The mutant line therefore affords us an opportunity to investigate the role of the corresponding protein in mechanoelectrical transduction.
Gleason
Michelle R
MR
Howard Hughes Medical Institute and Laboratory of Sensory Neuroscience, The Rockefeller University, New York, NY 10065, USA.
Nagiel
Aaron
A
Jamet
Sophie
S
Vologodskaia
Maria
M
López-Schier
Hernán
H
Hudspeth
A J
AJ
D000818:Animals; D003638:Deafness; D007758:Ear, Inner / Q000473:pathology; D016368:Frameshift Mutation; D006198:Hair Cells, Auditory / Q000473:pathology; D006309:Hearing / Q000502:physiology*; D040542:Mechanotransduction, Cellular / Q000235:genetics; D008565:Membrane Proteins / Q000235:genetics / Q000502:physiology*; D004856:Postural Balance / Q000502:physiology*; D015027:Zebrafish; D029961:Zebrafish Proteins / Q000235:genetics / Q000502:physiology*
D008565:Membrane Proteins; C530850:Tmie protein, zebrafish; D029961:Zebrafish Proteins