Reversal of contractility as a signature of self-organization in cytoskeletal bundles

  1. Martin Lenz  Is a corresponding author
  1. CNRS, France


Bundles of cytoskeletal filaments and molecular motors generate motion in living cells, and have internal structures ranging from very organized to apparently disordered. The mechanisms powering the disordered structures are debated, and existing models predominantly predict that they are contractile. We reexamine this prediction through a theoretical treatment of the interplay between three well-characterized internal dynamical processes in cytoskeletal bundles: filament assembly and disassembly, the attachment-detachment dynamics of motors and that of crosslinking proteins. The resulting self-organization is easily understood in terms of motor and crosslink localization, and allows for an extensive control of the active bundle mechanics, including reversals of the filaments' apparent velocities and the possibility of generating extension instead of contraction. This reversal mirrors some recent experimental observations, and provides a robust criterion to experimentally elucidate the underpinnings of both actomyosin activity and the dynamics of microtubule/motor assemblies in vitro as well as in diverse intracellular structures ranging from contractile bundles to the mitotic spindle.

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This study does not involve the generation or analysis of data.

Article and author information

Author details

  1. Martin Lenz

    LPTMS, CNRS, Orsay, France
    For correspondence
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-2307-1106


FP7 European Research Council (PCIG12-GA-2012-334053)

  • Martin Lenz

H2020 European Research Council (Stg677532)

  • Martin Lenz

LabEx PALM (ANR-10-LABX-0039- PALM)

  • Martin Lenz

Agence Nationale de la Recherche (ANR-15-CE13-0004-03)

  • Martin Lenz

The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.

Reviewing Editor

  1. Raymond E Goldstein, University of Cambridge, United Kingdom

Publication history

  1. Received: September 9, 2019
  2. Accepted: March 5, 2020
  3. Accepted Manuscript published: March 9, 2020 (version 1)
  4. Version of Record published: March 19, 2020 (version 2)


© 2020, Lenz

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. Martin Lenz
Reversal of contractility as a signature of self-organization in cytoskeletal bundles
eLife 9:e51751.

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