Depletion or cleavage of cohesin during anaphase differentially affects chromatin structure and segregation
- MRC London Institute of Medical Sciences, United Kingdom
- Institut Pasteur, France
Abstract
Chromosome segregation requires both the separation of sister chromatids and the sustained condensation of chromatids during anaphase. In yeast cells, cohesin is not only required for sister chromatid cohesion but also plays a major role determining the structure of individual chromatids in metaphase. Separase cleavage is thought to remove all cohesin complexes from chromosomes to initiate anaphase. It is thus not clear how the length and organisation of segregating chromatids is maintained during anaphase in the absence of cohesin. Here we show that degradation of cohesin at the anaphase onset causes aberrant chromatid segregation. Hi-C analysis on segregating chromatids demonstrates that cohesin depletion causes loss of intrachromatid organisation. Surprisingly, TEV-mediated cleavage of cohesin does not dramatically disrupt chromatid organisation in anaphase, explaining why bulk segregation is achieved. In addition, we identified a small pool of cohesin complexes bound to telophase chromosomes in wildtype cells and show that they play a role in the organisation of centromeric regions. Our data demonstrates that in yeast cells cohesin function is not over in metaphase, but extends to the anaphase period when chromatids are segregating.
Data availability
Sequencing data have been deposited in GEO under accession codesGSE183481
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Cohesin contribution to chromatid organisation is critical during chromosome segregation.NCBI Gene Expression Omnibus, GSE183481 Token to have access is cpghcwoajdonjix.
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FACT mediates cohesin function on chromatinGEO database. GSE118534.
Article and author information
Author details
Funding
Medical Research Council (UKRI MC-A652-5PY00)
- Luis Aragon
Agence Nationale de la Recherche
- Romain Koszul
Wellcome Trust (100955/Z/13/Z)
- Jonay Garcia-Luis
European Research Council
- Romain Koszul
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2022, Garcia-Luis 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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Depletion or cleavage of cohesin during anaphase differentially affects chromatin structure and segregation
eLife 11:e80147.
https://doi.org/10.7554/eLife.80147
Further reading
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