A positive feedback-based mechanism for constriction rate acceleration during cytokinesis in C. elegans
- University of California, San Diego, United States
Abstract
To ensure timely cytokinesis, the equatorial actomyosin contractile ring constricts at a relatively constant rate despite its progressively decreasing size. Thus, the per-unit-length constriction rate increases as ring perimeter decreases. To understand this acceleration, we monitored cortical surface and ring component dynamics during the first cytokinesis of the C. elegans embryo. We found that, per-unit-length, the amount of ring components (myosin, anillin) and the constriction rate increase with parallel exponential kinetics. Quantitative analysis of cortical flow indicated that the cortex within the ring is compressed along the axis perpendicular to the ring, and the per-unit-length rate of cortical compression increases during constriction in proportion to ring myosin. We propose that positive feedback between ring myosin and compression-driven flow of cortex into the ring drives an exponential increase in the per-unit-length amount of ring myosin to maintain a high ring constriction rate and support this proposal with an analytical mathematical model.
Data availability
All data generated during this study are included in the manuscript and supporting files.
Article and author information
Author details
Funding
Ludwig Institute for Cancer Research
- Arshad Desai
- Karen Oegema
Beckman Laser Institute and Medical Clinic
- Michael W Berns
Air Force Office of Scientific Research (FA9550-08-1-0284)
- Michael W Berns
Jane Coffin Childs Memorial Fund for Medical Research
- Renat N Khaliullin
National Institutes of Health (T32 CA067754)
- J Sebastian Gomez-Cavazo
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Reviewing Editor
- Mohan K Balasubramanian, University of Warwick, United Kingdom
Version history
- Received: February 20, 2018
- Accepted: July 1, 2018
- Accepted Manuscript published: July 2, 2018 (version 1)
- Accepted Manuscript updated: July 5, 2018 (version 2)
- Version of Record published: July 27, 2018 (version 3)
Copyright
© 2018, Khaliullin 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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A positive feedback-based mechanism for constriction rate acceleration during cytokinesis in C. elegans
eLife 7:e36073.
https://doi.org/10.7554/eLife.36073
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