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A two-state piezoelectric model for outer hair cell motility
1Biophysics Section, Laboratory of Cellular Biology, National Institute on Deafness and Other Communication Disorders, National Institutes of Health, Bethesda, Maryland 20892, USA. iwasa@nih.gov
Biophysical Journal
|October 19, 2001
Summary
Outer hair cells exhibit voltage-dependent motility explained by an area motor model. This study reveals the outer hair cell
Area of Science:
- Cellular mechanics
- Biophysics
- Piezoelectricity
Background:
- Outer hair cell (OHC) length changes are voltage-dependent, driven by membrane charge transfer.
- An "area motor" model explains OHC motility via conformational transitions and charge transfer.
Purpose of the Study:
- To demonstrate the piezoelectric nature of the OHC area motor.
- To characterize the piezoelectric properties of the outer hair cell.
Main Methods:
- Investigated the area motor model within the outer hair cell's lateral membrane.
- Analyzed the piezoelectric response of the outer hair cell.
Main Results:
- The area motor and the outer hair cell itself are shown to be piezoelectric.
- The outer hair cell possesses an exceptionally large piezoelectric coefficient, surpassing known materials by four orders of magnitude.
- Prominent nonlinearity in the outer hair cell's response is attributed to discrete motor states.
Conclusions:
- The outer hair cell functions as a highly efficient biological piezoelectric device.
- The unique piezoelectric properties of the outer hair cell are crucial for its auditory function.
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