1. Cell Biology
Download icon

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
  • Cited 26
  • Views 3,128
  • Annotations
Cite this article as: eLife 2017;6:e26120 doi: 10.7554/eLife.26120

Abstract

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.

Article and author information

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
    rcoliveira@igc.gulbenkian.pt
    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

Funding

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)

Copyright

© 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.

Metrics

  • 3,128
    Page views
  • 581
    Downloads
  • 26
    Citations

Article citation count generated by polling the highest count across the following sources: Scopus, Crossref, PubMed Central.

Download links

A two-part list of links to download the article, or parts of the article, in various formats.

Downloads (link to download the article as PDF)

Download citations (links to download the citations from this article in formats compatible with various reference manager tools)

Open citations (links to open the citations from this article in various online reference manager services)

Further reading

    1. Cell Biology
    2. Developmental Biology
    Yosuke Tona, Doris K Wu
    Research Advance

    The asymmetric hair bundle on top of hair cells (HCs), comprises a kinocilium and stereocilia staircase, dictates HC's directional sensitivity. The mother centriole (MC) forms the base of the kinocilium, where stereocilia are subsequently built next to it. Previously we showed that transcription factor Emx2 reverses hair bundle orientation and its expression in the mouse vestibular utricle is restricted, resulting in two regions of opposite bundle orientation (Jiang et al, 2017). Here, we investigated establishment of opposite bundle orientation in embryonic utricles by live-imaging GFP-labeled centrioles in HCs. The daughter centriole invariably migrated ahead of the MC from the center to their respective peripheral locations in HCs. Comparing HCs between utricular regions, centriole trajectories were similar but they migrated towards opposite directions, suggesting that Emx2 pre-patterned HCs prior to centriole migration. Ectopic Emx2, however, reversed centriole trajectory within hours during a critical time-window when centriole trajectory was responsive to Emx2.

    1. Biochemistry and Chemical Biology
    2. Cell Biology
    Mark Shaaya et al.
    Tools and Resources

    Engineered allosteric regulation of protein activity provides significant advantages for the development of robust and broadly applicable tools. However, the application of allosteric switches in optogenetics has been scarce and suffers from critical limitations. Here, we report an optogenetic approach that utilizes an engineered Light-Regulated (LightR) allosteric switch module to achieve tight spatiotemporal control of enzymatic activity. Using the tyrosine kinase Src as a model, we demonstrate efficient regulation of the kinase and identify temporally distinct signaling responses ranging from seconds to minutes. LightR-Src off-kinetics can be tuned by modulating the LightR photoconversion cycle. A fast cycling variant enables the stimulation of transient pulses and local regulation of activity in a selected region of a cell. The design of the LightR module ensures broad applicability of the tool, as we demonstrate by achieving light-mediated regulation of Abl and bRaf kinases as well as Cre recombinase.