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Reduced climbing and increased slipping adaptation in cochlear hair cells of mice with Myo7a mutations

Nature Neuroscience volume 5, pages 4147 (2002) | Download Citation

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Abstract

Mutations in Myo7a cause hereditary deafness in mice and humans. We describe the effects of two mutations, Myo7a6J and Myo7a4626SB, on mechano-electrical transduction in cochlear hair cells. Both mutations result in two major functional abnormalities that would interfere with sound transduction. The hair bundles need to be displaced beyond their physiological operating range for mechanotransducer channels to open. Transducer currents also adapt more strongly than normal to excitatory stimuli. We conclude that myosin VIIA participates in anchoring and holding membrane-bound elements to the actin core of the stereocilium. Myosin VIIA is therefore required for the normal gating of transducer channels.

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Acknowledgements

This work was supported by the MRC, Defeating Deafness and the EC. We thank J. Fleming for help with genotyping. G. Richardson is supported by the Wellcome Trust.

Author information

Author notes

    • C. J. Kros
    •  & W. Marcotti

    The first two authors contributed equally to this work

Affiliations

  1. School of Biological Sciences, University of Sussex, Falmer, Brighton BN1 9QG, UK

    • C. J. Kros
    • , W. Marcotti
    •  & G. P. Richardson
  2. Department of Physiology, School of Medical Sciences, University of Bristol, University Walk, Bristol BS8 1TD, UK

    • C. J. Kros
    •  & W. Marcotti
  3. Department of Neurobiophysics, University of Groningen, Nijenborgh 4, 9747 AG Groningen, The Netherlands

    • S. M. van Netten
  4. MRC Institute of Hearing Research, University of Nottingham, Nottingham NG7 2RD, UK

    • T. J. Self
    • , R. T Libby
    •  & K. P. Steel
  5. MRC Mammalian Genetics Unit, Harwell, Didcot, Oxfordshire OX11 0RD, UK

    • S. D. M. Brown

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The authors declare no competing financial interests.

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Correspondence to C. J. Kros.

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DOI

https://doi.org/10.1038/nn784

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