Control of lipid domain organization by a biomimetic contractile actomyosin cortex

  1. Sven Kenjiro Vogel  Is a corresponding author
  2. Ferdinand Greiss
  3. Alena Khmelinskaia
  4. Petra Schwille  Is a corresponding author
  1. Max-Planck Institute of Biochemistry, Germany

Abstract

The cell membrane is a heterogeneously organized composite with lipid-protein micro-domains. The contractile actin cortex may govern the lateral organization of these domains in the cell membrane, yet the underlying mechanisms are not known. Previously we have reconstituted minimal actin cortices (MACs; Vogel et al, 2013b). Here we investigate the effects of rearranging actin filaments on the lateral membrane organization by introducing various phase-separated lipid mono- and bilayers to the MACs. The addition of actin filaments reorganized membrane domains. We found that the process reached a steady state where line tension and lateral crowding balanced. Moreover, the phase boundary allowed myosin driven actin filament rearrangements to actively move individual lipid domains, often accompanied by their shape change, fusion or splitting. Our findings illustrate how actin cortex remodeling in cells may control dynamic rearrangements of lipids and other molecules inside domains without directly binding to actin filaments.

Article and author information

Author details

  1. Sven Kenjiro Vogel

    Max-Planck Institute of Biochemistry, Martinsried, Germany
    For correspondence
    svogel@biochem.mpg.de
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-2540-5947
  2. Ferdinand Greiss

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

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

    Max-Planck Institute of Biochemistry, Martinsried, Germany
    For correspondence
    schwille@biochem.mpg.de
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-6106-4847

Funding

Daimler und Benz Stiftung (32-09/11)

  • Sven Kenjiro Vogel

Max-Planck-Gesellschaft

  • Sven Kenjiro Vogel
  • Ferdinand Greiss
  • Alena Khmelinskaia
  • Petra Schwille

Bundesministerium für Bildung und Forschung

  • Sven Kenjiro Vogel
  • Petra Schwille

Deutsche Forschungsgemeinschaft (SCHW716/8-1)

  • Sven Kenjiro Vogel
  • Petra Schwille

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

Copyright

© 2017, Vogel 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. Sven Kenjiro Vogel
  2. Ferdinand Greiss
  3. Alena Khmelinskaia
  4. Petra Schwille
(2017)
Control of lipid domain organization by a biomimetic contractile actomyosin cortex
eLife 6:e24350.
https://doi.org/10.7554/eLife.24350

Share this article

https://doi.org/10.7554/eLife.24350

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