Active contraction of microtubule networks

  1. Peter J Foster  Is a corresponding author
  2. Sebastian Fürthauer
  3. Michael J Shelley
  4. Daniel J Needleman
  1. Harvard University, United States
  2. New York University, United States

Abstract

Many cellular processes are driven by cytoskeletal assemblies. It remains unclear how cytoskeletal filaments and motor proteins organize into cellular scale structures and how molecular properties of cytoskeletal components affect the large scale behaviors of these systems. Here we investigate the self-organization of stabilized microtubules in Xenopus oocyte extracts and find that they can form macroscopic networks that spontaneously contract. We propose that these contractions are driven by the clustering of microtubule minus ends by dynein. Based on this idea, we construct an active fluid theory of network contractions which predicts a dependence of the timescale of contraction on initial network geometry, a development of density inhomogeneities during contraction, a constant final network density, and a strong influence of dynein inhibition on the rate of contraction, all in quantitative agreement with experiments. These results demonstrate that the motor-driven clustering of filament ends is a generic mechanism leading to contraction.

Article and author information

Author details

  1. Peter J Foster

    John A. Paulson School of Engineering and Applied Sciences, FAS Center for Systems Biology, Harvard University, Cambridge, United States
    For correspondence
    peterfoster@fas.harvard.edu
    Competing interests
    The authors declare that no competing interests exist.
  2. Sebastian Fürthauer

    Courant Institute of Mathematical Science, New York University, New York, United States
    Competing interests
    The authors declare that no competing interests exist.
  3. Michael J Shelley

    Courant Institute of Mathematical Science, New York University, New York, United States
    Competing interests
    The authors declare that no competing interests exist.
  4. Daniel J Needleman

    John A. Paulson School of Engineering and Applied Sciences, FAS Center for Systems Biology, Harvard University, Cambridge, United States
    Competing interests
    The authors declare that no competing interests exist.

Ethics

Animal experimentation: All animals were handled according to approved institutional animal care and use committee (IACUC) protocols (#28-18) of Harvard University.

Reviewing Editor

  1. Anna Akhmanova, Utrecht University, Netherlands

Publication history

  1. Received: August 18, 2015
  2. Accepted: December 20, 2015
  3. Accepted Manuscript published: December 23, 2015 (version 1)
  4. Version of Record published: February 8, 2016 (version 2)

Copyright

© 2015, Foster 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. Peter J Foster
  2. Sebastian Fürthauer
  3. Michael J Shelley
  4. Daniel J Needleman
(2015)
Active contraction of microtubule networks
eLife 4:e10837.
https://doi.org/10.7554/eLife.10837
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