1. Physics of Living Systems
  2. Cell Biology

Side-binding proteins modulate actin filament dynamics

  1. Alvaro H Crevenna  Is a corresponding author
  2. Marcelino Arciniega
  3. Aurélie Dupont
  4. Naoko Mizuno
  5. Kaja Kowalska
  6. Oliver F Lange
  7. Roland Wedlich-Söldner
  8. Don C Lamb
  1. Ludwig Maximilian University of Munich, Germany
  2. Max Planck Institute of Biochemistry, Germany
  3. Technische Universität München, Germany
  4. University of Münster, Germany
https://doi.org/10.7554/eLife.04599
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Cite this article
  1. Alvaro H Crevenna
  2. Marcelino Arciniega
  3. Aurélie Dupont
  4. Naoko Mizuno
  5. Kaja Kowalska
  6. Oliver F Lange
  7. Roland Wedlich-Söldner
  8. Don C Lamb
(2015)
Side-binding proteins modulate actin filament dynamics
eLife 4:e04599.
https://doi.org/10.7554/eLife.04599
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Abstract

Actin filament dynamics govern many key physiological processes from cell motility to tissue morphogenesis. A central feature of actin dynamics is the capacity of filaments to polymerize and depolymerize at their ends in response to cellular conditions. It is currently thought that filament kinetics can be described by a single rate constant for each end. Here, using direct visualization of single actin filament elongation, we show that actin polymerization kinetics at both filament ends are strongly influenced by the binding of proteins to the lateral filament surface. We also show that the pointed-end has a non-elongating state that dominates the observed filament kinetic asymmetry. Estimates of flexibility as well as effects on fragmentation and growth suggest that the observed kinetic diversity arises from structural alteration. Tuning elongation kinetics by exploiting the malleability of the filament structure may be a ubiquitous mechanism to generate a rich variety of cellular actin dynamics.

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Author details

  1. Alvaro H Crevenna

    Physical Chemistry, Department of Chemistry and Center for Nanoscience, Ludwig Maximilian University of Munich, Munich, Germany
    For correspondence
    alvaro.crevenna@cup.uni-muenchen.de
    Competing interests
    The authors declare that no competing interests exist.

  2. Marcelino Arciniega

    Max Planck Institute of Biochemistry, Martinsried, Germany
    Competing interests
    The authors declare that no competing interests exist.

  3. Aurélie Dupont

    Physical Chemistry, Department of Chemistry and Center for Nanoscience, Ludwig Maximilian University of Munich, Munich, Germany
    Competing interests
    The authors declare that no competing interests exist.

  4. Naoko Mizuno

    Cellular and Membrane Trafficking, Max Planck Institute of Biochemistry, Martinsried, Germany
    Competing interests
    The authors declare that no competing interests exist.

  5. Kaja Kowalska

    Cellular Dynamics and Cell Patterning, Max Planck Institute of Biochemistry, Martinsried, Germany
    Competing interests
    The authors declare that no competing interests exist.

  6. Oliver F Lange

    Department of Chemistry, Technische Universität München, Garching, Germany
    Competing interests
    The authors declare that no competing interests exist.

  7. Roland Wedlich-Söldner

    Institute of Cell Dynamics and Imaging, University of Münster, Münster, Germany
    Competing interests
    The authors declare that no competing interests exist.

  8. Don C Lamb

    Physical Chemistry, Department for Chemistry and Center for Nanoscience, Ludwig Maximilian University of Munich, Munich, Germany
    Competing interests
    The authors declare that no competing interests exist.

Copyright

© 2015, Crevenna 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. Alvaro H Crevenna
  2. Marcelino Arciniega
  3. Aurélie Dupont
  4. Naoko Mizuno
  5. Kaja Kowalska
  6. Oliver F Lange
  7. Roland Wedlich-Söldner
  8. Don C Lamb
(2015)
Side-binding proteins modulate actin filament dynamics
eLife 4:e04599.
https://doi.org/10.7554/eLife.04599

Share this article

https://doi.org/10.7554/eLife.04599

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