1. Structural Biology and Molecular Biophysics
  2. Cell Biology
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Crenactin forms actin-like double helical filaments regulated by arcadin-2

  1. Thierry Izoré
  2. Danguole Kureisaite-Ciziene
  3. Stephen H McLaughlin
  4. Jan Löwe  Is a corresponding author
  1. MRC Laboratory of Molecular Biology, United Kingdom
Research Article
  • Cited 17
  • Views 1,533
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Cite this article as: eLife 2016;5:e21600 doi: 10.7554/eLife.21600

Abstract

The similarity of eukaryotic actin to crenactin, a filament-forming protein from the crenarchaeon Pyrobaculum calidifontis supports the theory of a common origin of Crenarchaea and Eukaryotes. Monomeric structures of crenactin and actin are similar, although their filament architectures were suggested to be different. Here we report that crenactin forms bona fide double helical filaments that show exceptional similarity to eukaryotic F-actin. With cryo-electron microscopy and helical reconstruction we solved the structure of the crenactin filament to 3.8 Å resolution. When forming double filaments, the 'hydrophobic plug' loop in crenactin rearranges. Arcadin-2, also encoded by the arcade gene cluster, binds tightly with its C-terminus to the hydrophobic groove of crenactin. Binding is reminiscent of eukaryotic actin modulators such as cofilin and thymosin β4 and arcadin-2 is a depolymeriser of crenactin filaments. Our work further supports the theory of shared ancestry of Eukaryotes and Crenarchaea.

Article and author information

Author details

  1. Thierry Izoré

    MRC Laboratory of Molecular Biology, Cambridge, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
  2. Danguole Kureisaite-Ciziene

    MRC Laboratory of Molecular Biology, Cambridge, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
  3. Stephen H McLaughlin

    MRC Laboratory of Molecular Biology, Cambridge, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-9135-6253
  4. Jan Löwe

    MRC Laboratory of Molecular Biology, Cambridge, United Kingdom
    For correspondence
    jyl@mrc-lmb.cam.ac.uk
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-5218-6615

Funding

Medical Research Council (U105184326)

  • Danguole Kureisaite-Ciziene
  • Stephen H McLaughlin
  • Jan Löwe

Wellcome (095514/Z/11/Z)

  • Thierry Izoré
  • Jan Löwe

European Molecular Biology Organization (ALTF 1379-2011)

  • Thierry Izoré

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

Reviewing Editor

  1. Werner Kühlbrandt, Max Planck Institute of Biophysics, Germany

Publication history

  1. Received: September 17, 2016
  2. Accepted: November 14, 2016
  3. Accepted Manuscript published: November 17, 2016 (version 1)
  4. Version of Record published: December 20, 2016 (version 2)

Copyright

© 2016, Izoré 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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