CTCF and cohesin regulate chromatin loop stability with distinct dynamics

  1. Anders S Hansen
  2. Iryna Pustova
  3. Claudia Cattoglio
  4. Robert Tjian
  5. Xavier Darzacq  Is a corresponding author
  1. University of California, Berkeley, United States

Abstract

Folding of mammalian genomes into spatial domains is critical for gene regulation. The insulator protein CTCF and cohesin control domain location by folding domains into loop structures, which are widely thought to be stable. Combining genomic and biochemical approaches we show that CTCF and cohesin co-occupy the same sites and physically interact as a biochemically stable complex. However, using single-molecule imaging we find that CTCF binds chromatin much more dynamically than cohesin (~1-2 min vs. ~22 min residence time). Moreover, after unbinding, CTCF quickly rebinds another cognate site unlike cohesin for which the search process is long (~1 min vs. ~33 min). Thus, CTCF and cohesin form a rapidly exchanging "dynamic complex" rather than a typical stable complex. Since CTCF and cohesin are required for loop domain formation, our results suggest that chromatin loops are dynamic and constantly break and reform throughout the cell cycle.

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The following data sets were generated
The following previously published data sets were used

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Author details

  1. Anders S Hansen

    Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, United States
    Competing interests
    No competing interests declared.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-7540-7858
  2. Iryna Pustova

    Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, United States
    Competing interests
    No competing interests declared.
  3. Claudia Cattoglio

    Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, United States
    Competing interests
    No competing interests declared.
  4. Robert Tjian

    Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, United States
    Competing interests
    Robert Tjian, President of the Howard Hughes Medical Institute (2009-present), one of the three founding funders of eLife, and a member of eLife's Board of Directors..
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-0539-8217
  5. Xavier Darzacq

    Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, United States
    For correspondence
    darzacq@berkeley.edu
    Competing interests
    No competing interests declared.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-2537-8395

Funding

Siebel Stem Cell Institute (NA)

  • Anders S Hansen

Howard Hughes Medical Institute (3061)

  • Robert Tjian

California Institute of Regenerative Medicine (LA1-08013)

  • Xavier Darzacq

National Institutes of Health (UO1-EB021236 U54-DK107980)

  • Xavier Darzacq

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

Reviewing Editor

  1. David Sherratt, University of Oxford, United Kingdom

Publication history

  1. Received: February 6, 2017
  2. Accepted: April 30, 2017
  3. Accepted Manuscript published: May 3, 2017 (version 1)
  4. Version of Record published: May 26, 2017 (version 2)

Copyright

© 2017, Hansen 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. Anders S Hansen
  2. Iryna Pustova
  3. Claudia Cattoglio
  4. Robert Tjian
  5. Xavier Darzacq
(2017)
CTCF and cohesin regulate chromatin loop stability with distinct dynamics
eLife 6:e25776.
https://doi.org/10.7554/eLife.25776

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