Mesoscale phase separation of chromatin in the nucleus

  1. Gaurav Bajpai  Is a corresponding author
  2. Daria Amiad Pavlov
  3. Dana Lorber
  4. Talila Volk
  5. Samuel Safran  Is a corresponding author
  1. Weizmann Institute of Science, Israel

Abstract

Intact-organism imaging of Drosophila larvae reveals and quantifies chromatin-aqueous phase separation. The chromatin can be organized near the lamina layer of the nuclear envelope, conventionally fill the nucleus, be organized centrally, or as a wetting droplet. These transitions are controlled by changes in nuclear volume and the interaction of chromatin with the lamina (part of the nuclear envelope) at the nuclear periphery. Using a simple polymeric model that includes the key features of chromatin self-attraction and its binding to the lamina, we demonstrate theoretically that it is the competition of these two effects that determines the mode of chromatin distribution. The qualitative trends as well as the composition profiles obtained in our simulations compare well with the observed intact-organism imaging and quantification. Since the simulations contain only a small number of physical variables we can identify the generic mechanisms underlying the changes in the observed phase separations.

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. Gaurav Bajpai

    Department of Chemical and Biological Physics, Weizmann Institute of Science, Rehovot, Israel
    For correspondence
    gaurav.bajpai@weizmann.ac.il
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-3875-4599
  2. Daria Amiad Pavlov

    Department of Molecular Genetics, Weizmann Institute of Science, Rehovot, Israel
    Competing interests
    The authors declare that no competing interests exist.
  3. Dana Lorber

    Molecular Genetics, Weizmann Institute of Science, Rehovot, Israel
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-0635-8703
  4. Talila Volk

    Department of Molecular Genetics, Weizmann Institute of Science, Rehovot, Israel
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-3800-2621
  5. Samuel Safran

    Department of Chemical and Biological Physics, Weizmann Institute of Science, Rehovot, Israel
    For correspondence
    sam.safran@weizmann.ac.il
    Competing interests
    The authors declare that no competing interests exist.

Funding

Perlman Family Foundation

  • Samuel Safran

Volkswagen Foundation

  • Samuel Safran

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

Reviewing Editor

  1. Karsten Kruse, University of Geneva, Switzerland

Publication history

  1. Received: October 13, 2020
  2. Accepted: April 30, 2021
  3. Accepted Manuscript published: May 4, 2021 (version 1)
  4. Version of Record published: May 21, 2021 (version 2)
  5. Version of Record updated: May 26, 2021 (version 3)

Copyright

© 2021, Bajpai 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. Gaurav Bajpai
  2. Daria Amiad Pavlov
  3. Dana Lorber
  4. Talila Volk
  5. Samuel Safran
(2021)
Mesoscale phase separation of chromatin in the nucleus
eLife 10:e63976.
https://doi.org/10.7554/eLife.63976

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