Curvature-induced expulsion of actomyosin bundles during cytokinetic ring contraction
- University of Warwick, United Kingdom
- King's College London, United Kingdom
- Lawrence University, United States
Abstract
Many eukaryotes assemble a ring-shaped actomyosin network that contracts to drive cytokinesis. Unlike actomyosin in sarcomeres, which cycles through contraction and relaxation, the cytokinetic ring disassembles during contraction through an unknown mechanism. Here we find in Schizosaccharomyces japonicus and Schizosaccharomyces pombe that, during actomyosin ring contraction, actin filaments associated with actomyosin rings are expelled as micron-scale bundles containing multiple actomyosin ring proteins. Using functional isolated actomyosin rings we show that expulsion of actin bundles does not require continuous presence of cytoplasm. Strikingly, mechanical compression of actomyosin rings results in expulsion of bundles predominantly at regions of high curvature. Our work unprecedentedly reveals that the increased curvature of the ring itself promotes its disassembly. It is likely that such a curvature-induced mechanism may operate in disassembly of other contractile networks.
Article and author information
Author details
Robert Anthony Cross
Mohan K Balasubramanian
Funding
Wellcome (WT101885MA)
- Mohan K Balasubramanian
Royal Society
- Mohan K Balasubramanian
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2016, Huang 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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Curvature-induced expulsion of actomyosin bundles during cytokinetic ring contraction
eLife 5:e21383.
https://doi.org/10.7554/eLife.21383
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