Contractile acto-myosin network on nuclear envelope remnants positions human chromosomes for mitosis
- University of Dundee, United Kingdom
- University of Sussex, United Kingdom
- University of Minnesota, United States
Abstract
To ensure proper segregation during mitosis, chromosomes must be efficiently captured by spindle microtubules and subsequently aligned on the mitotic spindle. The efficacy of chromosome interaction with the spindle can be influenced by how widely chromosomes are scattered in space. Here, we quantify chromosome-scattering volume (CSV) and find that it is reduced soon after nuclear envelope breakdown (NEBD) in human cells. The CSV reduction occurs primarily independently of microtubules and is therefore not an outcome of interactions between chromosomes and the spindle. We find that, prior to NEBD, an acto-myosin network is assembled in a LINC complex-dependent manner on the cytoplasmic surface of the nuclear envelope. This acto-myosin network remains on nuclear envelope remnants soon after NEBD, and its myosin-II-mediated contraction reduces CSV and facilitates timely chromosome congression and correct segregation. Thus we find a novel mechanism that positions chromosomes in early mitosis to ensure efficient and correct chromosome-spindle interactions.
Data availability
A source data file has been provided for each figure, and it contains the source data at individual time points in individual cells where relevant.
Article and author information
Author details
Alexander JR Booth
Funding
Wellcome (096535/Z/11/Z)
- Tomoyuki Tanaka
Wellcome (097945/Z/11/Z)
- Tomoyuki Tanaka
Wellcome (208401/Z/17/Z)
- Tomoyuki Tanaka
Cancer Research UK (C28206/A114499)
- Helfrid Hochegger
Medical Research Council (MR/K015869/1)
- Tomoyuki Tanaka
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2019, Booth 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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Contractile acto-myosin network on nuclear envelope remnants positions human chromosomes for mitosis
eLife 8:e46902.
https://doi.org/10.7554/eLife.46902
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