1. Physics of Living Systems
  2. Neuroscience
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Direct mechanical stimulation of tip links in hair cells through DNA tethers

  1. Aakash Basu
  2. Samuel Lagier
  3. Maria Vologodskaia
  4. Brian A Fabella
  5. A J Hudspeth  Is a corresponding author
  1. Howard Hughes Medical Institute, The Rockefeller University, United States
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Cite this article as: eLife 2016;5:e16041 doi: 10.7554/eLife.16041

Abstract

Mechanoelectrical transduction by hair cells commences with hair-bundle deflection, which is postulated to tense filamentous tip links connected to transduction channels. Because direct mechanical stimulation of tip links has not been experimentally possible, this hypothesis has not been tested directly. We have engineered DNA tethers that link superparamagnetic beads to tip links and exert mechanical forces on the links when exposed to a magnetic-field gradient. By pulling directly on tip links of the bullfrog's sacculus we have evoked transduction currents from hair cells, confirming the hypothesis that tension in the tip links opens transduction channels. This demonstration of direct mechanical access to tip links additionally lays a foundation for experiments probing the mechanics of individual channels.

Article and author information

Author details

  1. Aakash Basu

    Laboratory of Sensory Neuroscience, Howard Hughes Medical Institute, The Rockefeller University, New York, United States
    Competing interests
    The authors declare that no competing interests exist.
  2. Samuel Lagier

    Laboratory of Sensory Neuroscience, Howard Hughes Medical Institute, The Rockefeller University, New York, United States
    Competing interests
    The authors declare that no competing interests exist.
  3. Maria Vologodskaia

    Laboratory of Sensory Neuroscience, Howard Hughes Medical Institute, The Rockefeller University, New York, United States
    Competing interests
    The authors declare that no competing interests exist.
  4. Brian A Fabella

    Laboratory of Sensory Neuroscience, Howard Hughes Medical Institute, The Rockefeller University, New York, United States
    Competing interests
    The authors declare that no competing interests exist.
  5. A J Hudspeth

    Laboratory of Sensory Neuroscience, Howard Hughes Medical Institute, The Rockefeller University, New York, United States
    For correspondence
    hudspaj@rockefeller.edu
    Competing interests
    The authors declare that no competing interests exist.

Ethics

Animal experimentation: All procedures were approved by the University's Institutional Animal Care and Use Committee under protocol 13665. Animals were sacrificed by dual pithing after anesthesia by immersion in ethyl-3-aminobenzoate methanesulfonic acid.

Reviewing Editor

  1. Frank Jülicher, Max Planck Institute for the Physics of Complex Systems, Germany

Publication history

  1. Received: March 15, 2016
  2. Accepted: June 21, 2016
  3. Accepted Manuscript published: June 22, 2016 (version 1)
  4. Version of Record published: July 19, 2016 (version 2)

Copyright

© 2016, Basu et al.

This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.

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