The synaptonemal complex has liquid crystalline properties and spatially regulates meiotic recombination factors

  1. Ofer Rog  Is a corresponding author
  2. Simone Köhler
  3. Abby F Dernburg  Is a corresponding author
  1. University of Utah, United States
  2. University of California, Berkeley, United States

Abstract

The synaptonemal complex (SC) is a polymer that spans ~100nm between paired homologous chromosomes during meiosis. Its striated, periodic appearance in electron micrographs led to the idea that transverse filaments within this structure 'crosslink' the axes of homologous chromosomes, stabilizing their pairing. SC proteins can also form polycomplexes, three-dimensional lattices that recapitulate the periodic structure of SCs but do not associate with chromosomes. Here we provide evidence that SCs and polycomplexes contain mobile subunits and that their assembly is promoted by weak hydrophobic interactions, indicative of a liquid crystalline phase. We further show that in the absence of recombination intermediates, polycomplexes recapitulate the dynamic localization of pro-crossover factors during meiotic progression, revealing how the SC might act as a conduit to regulate chromosome-wide crossover distribution. Properties unique to liquid crystals likely enable long-range signal transduction along meiotic chromosomes and underlie the rapid evolution of SC proteins.

Article and author information

Author details

  1. Ofer Rog

    Biology Department, University of Utah, Salt Lake City, United States
    For correspondence
    ofer.rog@utah.edu
    Competing interests
    The authors declare that no competing interests exist.
  2. Simone Köhler

    Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, United States
    Competing interests
    The authors declare that no competing interests exist.
  3. Abby F Dernburg

    Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, United States
    For correspondence
    afdernburg@lbl.gov
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-8037-1079

Funding

Howard Hughes Medical Institute

  • Abby F Dernburg

National Institutes of Health (GM065591)

  • Abby F Dernburg

European Molecular Biology Organization (ALTF 564-2010)

  • Ofer Rog

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

Reviewing Editor

  1. Anthony A Hyman, Max Planck Institute of Molecular Cell Biology and Genetics, Germany

Publication history

  1. Received: September 12, 2016
  2. Accepted: January 2, 2017
  3. Accepted Manuscript published: January 3, 2017 (version 1)
  4. Version of Record published: January 26, 2017 (version 2)

Copyright

© 2017, Rog 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. Ofer Rog
  2. Simone Köhler
  3. Abby F Dernburg
(2017)
The synaptonemal complex has liquid crystalline properties and spatially regulates meiotic recombination factors
eLife 6:e21455.
https://doi.org/10.7554/eLife.21455
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