1. Cell Biology
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Axial contraction and short-range compaction of chromatin synergistically promote mitotic chromosome condensation

  1. Tom Kruitwagen
  2. Annina Denoth-Lippuner
  3. Bryan J Wilkins
  4. Heinz Neumann
  5. Yves Barral  Is a corresponding author
  1. Eidgenössische Technische Hochschule Zürich, Switzerland
  2. Georg- August University Göttingen
Research Article
  • Cited 16
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Cite this article as: eLife 2015;4:e10396 doi: 10.7554/eLife.10396

Abstract

The mitotic segregation of chromosomes requires their extensive folding into units of manageable size. Here, we report on how phosphorylation at serine 10 of histone H3 contributes to this process. We developed a fluorescence-based assay to study local compaction of chromatin in living yeast cells and show that chromosome condensation entails two temporally and mechanistically independent processes. Initially, nucleosome-nucleosome interactions triggered by phosphorylation of S10 on H3 and deacetylation of K16 on histone H4 promote short-range compaction of chromatin during early mitosis. Subsequently, condensin mediates the axial contraction of chromosome arms, peaking in late anaphase. Whereas defects in chromatin compaction did not impair axial contraction and condensin inactivation did not affect short-range chromatin compaction, inactivation of both pathways caused synergistic defects in chromosome segregation and cell viability. Interestingly, both pathways rely on the deacetylase Hst2, suggesting that Hst2 coordinates chromatin compaction and axial contraction to shape mitotic chromosomes.

Article and author information

Author details

  1. Tom Kruitwagen

    Institute of Biochemistry, Department of Biology, Eidgenössische Technische Hochschule Zürich, Zürich, Switzerland
    Competing interests
    No competing interests declared.
  2. Annina Denoth-Lippuner

    Institute of Biochemistry, Department of Biology, Eidgenössische Technische Hochschule Zürich, Zürich, Switzerland
    Competing interests
    No competing interests declared.
  3. Bryan J Wilkins

    Free Floater (Junior) Research Group Applied Synthetic Biology, Georg- August University Göttingen
    Competing interests
    Bryan J Wilkins, : Conception and design: NoAcquisition of data: YesAnalysis and interpretation of data: YesDrafting or revising the article: NoContributed unpublished essential data or reagents: No.
  4. Heinz Neumann

    Free Floater (Junior) Research Group Applied Synthetic Biology, Georg- August University Göttingen
    Competing interests
    Heinz Neumann, : Conception and design: NoAcquisition of data: NoAnalysis and interpretation of data: YesDrafting or revising the article: YesContributed unpublished essential data or reagents: No.
  5. Yves Barral

    Institute of Biochemistry, Department of Biology, Eidgenössische Technische Hochschule Zürich, Zürich, Switzerland
    For correspondence
    yves.barral@bc.biol.ethz.ch
    Competing interests
    No competing interests declared.

Reviewing Editor

  1. Mohan Balasubramanian, University of Warwick, United Kingdom

Publication history

  1. Received: July 30, 2015
  2. Accepted: November 27, 2015
  3. Accepted Manuscript published: November 28, 2015 (version 1)
  4. Version of Record published: February 3, 2016 (version 2)

Copyright

© 2015, Kruitwagen 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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