Bidirectional helical motility of cytoplasmic dynein around microtubules

  1. Sinan Can
  2. Mark A Dewitt
  3. Ahmet Yildiz  Is a corresponding author
  1. University of California, Berkeley, United States

Abstract

Cytoplasmic dynein is a molecular motor responsible for minus-end directed motility along microtubules (MTs). Dynein motility has previously been studied on surface-immobilized MTs, which constrains the motors to move in two dimensions. Here, we explored the full trajectory of dynein motility in three dimensions using an MT bridge assay. We found that dynein moves in a helical trajectory around the MT with an average pitch of ~500 nm. Unlike other cytoskeletal motors that produce torque in a specific direction, dynein generates torque in either direction, resulting in bidirectional helical motion. Dynein has a net preference for right-handed rotation, suggesting that the heads tend to bind to the closest tubulin binding site when taking sideways steps. This bidirectional helical motility may allow dynein to avoid roadblocks in dense cytoplasmic environments during cargo transport.

Article and author information

Author details

  1. Sinan Can

    University of California, Berkeley, Berkeley, United States
    Competing interests
    The authors declare that no competing interests exist.
  2. Mark A Dewitt

    University of California, Berkeley, Berkeley, United States
    Competing interests
    The authors declare that no competing interests exist.
  3. Ahmet Yildiz

    University of California, Berkeley, Berkeley, United States
    For correspondence
    yildiz@berkeley.edu
    Competing interests
    The authors declare that no competing interests exist.

Reviewing Editor

  1. Anthony A Hyman, Max Planck Institute of Molecular Cell Biology and Genetics, Germany

Version history

  1. Received: April 27, 2014
  2. Accepted: July 25, 2014
  3. Accepted Manuscript published: July 28, 2014 (version 1)
  4. Version of Record published: August 20, 2014 (version 2)

Copyright

© 2014, Can 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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  1. Sinan Can
  2. Mark A Dewitt
  3. Ahmet Yildiz
(2014)
Bidirectional helical motility of cytoplasmic dynein around microtubules
eLife 3:e03205.
https://doi.org/10.7554/eLife.03205

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https://doi.org/10.7554/eLife.03205

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