Membrane binding controls ordered self-assembly of animal septins

  1. Agata Szuba
  2. Fouzia Bano
  3. Gerard Castro Linares
  4. Francois Iv
  5. Manos Mavrakis  Is a corresponding author
  6. Ralf P Richter  Is a corresponding author
  7. Aurélie Bertin  Is a corresponding author
  8. Gijsje H Koenderink  Is a corresponding author
  1. University of Leeds, United Kingdom
  2. Umeå Universitet, Sweden
  3. Delft University of Technology, Netherlands
  4. Aix-Marseille Univ, France
  5. Institut Curie, France

Abstract

Septins are conserved cytoskeletal proteins that regulate cell cortex mechanics. The mechanisms of their interactions with the plasma membrane remain poorly understood. Here we show by cell-free reconstitution that binding to flat lipid membranes requires electrostatic interactions of septins with anionic lipids and promotes the ordered self-assembly of fly septins into filamentous meshworks. Transmission electron microscopy reveals that both fly and mammalian septin hexamers form arrays of single and paired filaments. Atomic force microscopy and quartz crystal microbalance demonstrate that the fly filaments form mechanically rigid, 12 to 18 nm thick, double layers of septins. By contrast, C-terminally truncated septin mutants form 4 nm thin monolayers, indicating that stacking requires the C-terminal coiled coils on DSep2 and Pnut subunits. Our work shows that membrane binding is required for fly septins to form ordered arrays of single and paired filaments and provides new insights into the mechanisms by which septins may regulate cell surface mechanics.

Data availability

All data generated or analysed during this study are included in the manuscript and supporting files.

Article and author information

Author details

  1. Agata Szuba

    Pollard Institute, School of Electronic & Electrical Engineering, University of Leeds, Leeds, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
  2. Fouzia Bano

    Department of Clinical Microbiology, Umeå Universitet, Umeå, Sweden
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-0634-7091
  3. Gerard Castro Linares

    Bionanoscience Department, Delft University of Technology, Delft, Netherlands
    Competing interests
    The authors declare that no competing interests exist.
  4. Francois Iv

    Institut Fresnel, CNRS, Aix-Marseille Univ, Marseille, France
    Competing interests
    The authors declare that no competing interests exist.
  5. Manos Mavrakis

    Institut Fresnel, CNRS, Aix-Marseille Univ, Marseille, France
    For correspondence
    manos.mavrakis@univ-amu.fr
    Competing interests
    The authors declare that no competing interests exist.
  6. Ralf P Richter

    School of Biomedical Sciences, Faculty of Biological Sciences, School of Physics and Astronomy, Faculty of Engineering and Physical Sciences, Astbury Centre for Structural Molecular Biology, and Bra, University of Leeds, Leeds, United Kingdom
    For correspondence
    R.Richter@leeds.ac.uk
    Competing interests
    The authors declare that no competing interests exist.
  7. Aurélie Bertin

    Laboratoire Physico Chimie Curie, Institut Curie, Paris, France
    For correspondence
    aurelie.bertin@curie.fr
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-3400-6887
  8. Gijsje H Koenderink

    Bionanoscience Department, Delft University of Technology, Delft, Netherlands
    For correspondence
    g.h.koenderink@tudelft.nl
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-7823-8807

Funding

H2020 European Research Council (ERC StG 335672,MINICELL)

  • Gijsje H Koenderink

H2020 European Research Council (ERC StG 306435; JELLY)

  • Ralf P Richter

Biotechnology and Biological Sciences Research Council (Equipment grant BB/R000174/1)

  • Ralf P Richter

Agence Nationale de la Recherche (ANR-13-JSV8-0002-01)

  • Manos Mavrakis
  • Aurélie Bertin

Agence Nationale de la Recherche (ANR-17-CE13-0014)

  • Manos Mavrakis
  • Aurélie Bertin

Fondation ARC pour la Recherche sur le Cancer (PJA 20151203182)

  • Manos Mavrakis
  • Aurélie Bertin

Nederlandse Organisatie voor Wetenschappelijk Onderzoek (024.003.019)

  • Gijsje H Koenderink

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

Reviewing Editor

  1. Mohan K Balasubramanian, University of Warwick, United Kingdom

Version history

  1. Received: September 22, 2020
  2. Accepted: April 12, 2021
  3. Accepted Manuscript published: April 13, 2021 (version 1)
  4. Version of Record published: May 5, 2021 (version 2)

Copyright

© 2021, Szuba 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. Agata Szuba
  2. Fouzia Bano
  3. Gerard Castro Linares
  4. Francois Iv
  5. Manos Mavrakis
  6. Ralf P Richter
  7. Aurélie Bertin
  8. Gijsje H Koenderink
(2021)
Membrane binding controls ordered self-assembly of animal septins
eLife 10:e63349.
https://doi.org/10.7554/eLife.63349

Share this article

https://doi.org/10.7554/eLife.63349

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