Mesoscale phase separation of chromatin in the nucleus
- 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
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
- Karsten Kruse, University of Geneva, Switzerland
Version history
- Received: October 13, 2020
- Accepted: April 30, 2021
- Accepted Manuscript published: May 4, 2021 (version 1)
- Version of Record published: May 21, 2021 (version 2)
- 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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Mesoscale phase separation of chromatin in the nucleus
eLife 10:e63976.
https://doi.org/10.7554/eLife.63976
Further reading
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- Developmental Biology
- Physics of Living Systems
Geometric criteria can be used to assess whether cell intercalation is active or passive during the convergent extension of tissue.
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