1. Structural Biology and Molecular Biophysics
  2. Chromosomes and Gene Expression
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Compaction and segregation of sister chromatids via active loop extrusion

  1. Anton Goloborodko
  2. Maxim V Imakaev
  3. John F Marko
  4. Leonid Mirny  Is a corresponding author
  1. Massachusetts Institute of Technology, United States
  2. Northwestern University, United States
Research Article
  • Cited 138
  • Views 6,589
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Cite this article as: eLife 2016;5:e14864 doi: 10.7554/eLife.14864

Abstract

The mechanism by which chromatids and chromosomes are segregated during mitosis and meiosis is a major puzzle of biology and biophysics. Using polymer simulations of chromosome dynamics, we show that a single mechanism of loop extrusion by condensins can robustly compact, segregate and disentangle chromosomes, arriving at individualized chromatids with morphology observed in vivo. Our model resolves the paradox of topological simplification concomitant with chromosome 'condensation', and explains how enzymes a few nanometers in size are able to control chromosome geometry and topology at micron length scales. We suggest that loop extrusion is a universal mechanism of genome folding that mediates functional interactions during interphase and compacts chromosomes during mitosis.

Article and author information

Author details

  1. Anton Goloborodko

    Department of Physics, Massachusetts Institute of Technology, Cambridge, United States
    Competing interests
    The authors declare that no competing interests exist.
  2. Maxim V Imakaev

    Department of Physics, Massachusetts Institute of Technology, Cambridge, United States
    Competing interests
    The authors declare that no competing interests exist.
  3. John F Marko

    Department of Molecular Biosciences, Department of Physics and Astronomy, Northwestern University, Evanston, United States
    Competing interests
    The authors declare that no competing interests exist.
  4. Leonid Mirny

    Department of Physics, Massachusetts Institute of Technology, Cambridge, United States
    For correspondence
    leonid@mit.edu
    Competing interests
    The authors declare that no competing interests exist.

Reviewing Editor

  1. Antoine M van Oijen, University of Groningen, Netherlands

Publication history

  1. Received: January 31, 2016
  2. Accepted: May 18, 2016
  3. Accepted Manuscript published: May 18, 2016 (version 1)
  4. Version of Record published: June 20, 2016 (version 2)

Copyright

© 2016, Goloborodko 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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