1. Cell Biology
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Metaphase chromosome structure is dynamically maintained by Condensin I-directed DNA (de)catenation

  1. Ewa Piskadlo
  2. Alexandra Tavares
  3. Raquel A Oliveira  Is a corresponding author
  1. Instituto Gulbenkian de Ciência, Portugal
Research Article
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Cite this article as: eLife 2017;6:e26120 doi: 10.7554/eLife.26120


Mitotic chromosome assembly remains a big mystery in biology. Condensin complexes are pivotal for chromosome architecture yet how they shape mitotic chromatin remains unknown. Using acute inactivation approaches and live-cell imaging in Drosophila embryos, we dissect the role of condensin I in the maintenance of mitotic chromosome structure with unprecedented temporal resolution. Removal of condensin I from pre-established chromosomes results in rapid disassembly of centromeric regions while most chromatin mass undergoes hyper-compaction. This is accompanied by drastic changes in the degree of sister chromatid intertwines. While wild-type metaphase chromosomes display residual levels of catenations, upon timely removal of condensin I, chromosomes present high levels of de novo Topoisomerase II (TopoII)-dependent re-entanglements, and complete failure in chromosome segregation. TopoII is thus capable of re-intertwining previously separated DNA molecules and condensin I continuously required to counteract this erroneous activity. We propose that maintenance of chromosome resolution is a highly dynamic bidirectional process.

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Author details

  1. Ewa Piskadlo

    Instituto Gulbenkian de Ciência, Oeiras, Portugal
    Competing interests
    The authors declare that no competing interests exist.
  2. Alexandra Tavares

    Instituto Gulbenkian de Ciência, Oeiras, Portugal
    Competing interests
    The authors declare that no competing interests exist.
  3. Raquel A Oliveira

    Instituto Gulbenkian de Ciência, Oeiras, Portugal
    For correspondence
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-8293-8603


Fundação para a Ciência e a Tecnologia (SRFH/BD/52172/2013)

  • Ewa Piskadlo

European Commission (MCCIG321883/CCC)

  • Raquel A Oliveira

European Molecular Biology Organization (IG2778)

  • Raquel A Oliveira

Fundação para a Ciência e a Tecnologia (IF/00851/2012/CP0185/CT0004 WP1)

  • Raquel A Oliveira

European Commission (ERC-2014-STG-638917-ChromoCellDev)

  • Raquel A Oliveira

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 18, 2017
  2. Accepted: May 5, 2017
  3. Accepted Manuscript published: May 6, 2017 (version 1)
  4. Version of Record published: May 31, 2017 (version 2)


© 2017, Piskadlo 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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