1. Chromosomes and Gene Expression

Cohesin architecture and clustering in vivo

  1. Siheng Xiang
  2. Douglas Koshland  Is a corresponding author
  1. University of California, Berkeley, United States
https://doi.org/10.7554/eLife.62243
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  1. Siheng Xiang
  2. Douglas Koshland
(2021)
Cohesin architecture and clustering in vivo
eLife 10:e62243.
https://doi.org/10.7554/eLife.62243
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Abstract

Cohesin helps mediate sister chromatid cohesion, chromosome condensation, DNA repair and transcription regulation. We exploited proximity-dependent labeling to define the in vivo interactions of cohesin domains with DNA or with other cohesin domains that lie within the same or in different cohesin complexes. Our results suggest both cohesin's head and hinge domains bind to DNA, and cohesin structure is dynamic with differential folding of its coiled coil regions to generate butterfly confirmations. This method also reveals that cohesins form ordered clusters on and off DNA. The levels of cohesin clusters and their distribution on chromosomes are cell cycle-regulated. Cohesin clustering is likely necessary for cohesion maintenance because clustering and maintenance uniquely require the same subset of cohesin domains and the auxiliary cohesin factor Pds5p. These conclusions provide important new mechanistic and biological insights into the architecture of the cohesin complex, cohesin-cohesin interactions, and cohesin's tethering and loop extruding activities.

Data availability

Sequencing data have been deposited in GEO as GSE157155.

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

Article and author information

Author details

  1. Siheng Xiang

    Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, United States
    Competing interests
    The authors declare that no competing interests exist.

  2. Douglas Koshland

    Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, United States
    For correspondence
    koshland@berkeley.edu
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-3742-6294

Funding

Helen Hay Whitney Foundation

  • Siheng Xiang

National Institute of General Medical Sciences (1R35 GM-118189-01)

  • Douglas Koshland

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

Copyright

© 2021, Xiang & Koshland

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. Siheng Xiang
  2. Douglas Koshland
(2021)
Cohesin architecture and clustering in vivo
eLife 10:e62243.
https://doi.org/10.7554/eLife.62243

Share this article

https://doi.org/10.7554/eLife.62243

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