Multiple inputs ensure yeast cell size homeostasis during cell cycle progression
Abstract
Coordination of cell growth with division is essential for proper cell function. In budding yeast, although some molecular mechanisms responsible for cell size control during G1 have been elucidated, the mechanism by which cell size homeostasis is established remains to be discovered. Here, we developed a new technique based on quantification of histone levels to monitor cell cycle progression in individual cells with unprecedented accuracy. Our analysis establishes the existence of a mechanism controlling bud size in G2/M that prevents premature onset of anaphase, and controls the overall size variability. While most G1 mutants do not display impaired size homeostasis, mutants in which Cyclin B-Cdk regulation is altered display large size variability. Our study thus demonstrates that size homeostasis is not controlled by a G1-specific mechanism alone but is likely to be an emergent property resulting from the integration of several mechanisms that coordinate cell and bud growth with division.
Data availability
The raw cell cycle data are available on a dedicated server http://charvin.igbmc.science/yeastcycledynamics/ and further details on how to use the site are available in Appendix 1. The autotrack software is available at GitHub: https://github.com/gcharvin/autotrack
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Yeast Cell Cycle DynamicsPublicly available at the URL cited.
Article and author information
Author details
Funding
Atip-avenir CNRS/Inserm
- Gilles Charvin
Agence Nationale de la Recherche (ANR-10-LABX-0030-INRT)
- Gilles Charvin
Agence Nationale de la Recherche (ANR-10-IDEX-0002-02)
- Gilles Charvin
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2018, Garmendia-Torres 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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