Reliable cell cycle commitment in budding yeast is ensured by signal integration
- Harvard University, United States
- Peking University, China
- China Three Gorges University, China
Abstract
Cell fate decisions are critical for life, yet little is known about how their reliability is achieved when signals are noisy and fluctuating with time. Here we show that in budding yeast, the decision of cell cycle commitment (Start) is determined by the time integration of its triggering signal Cln3. We further identify the Start repressor, Whi5 as the integrator. The instantaneous kinase activity of Cln3-Cdk1 is recorded over time on the phosphorylated Whi5, and the decision is made only when phosphorylated Whi5 reaches a threshold. Cells adjust the threshold by modulating Whi5 concentration in different nutrient conditions to coordinate growth and division. Our work shows that the strategy of signal integration, which was previously found in decision-making behaviors of animals, is adopted at the cellular level to reduce noise and minimize uncertainty.
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Author details
Reviewing Editor
- James Ferrell, Stanford University, United States
Version history
- Received: July 11, 2014
- Accepted: January 7, 2015
- Accepted Manuscript published: January 15, 2015 (version 1)
- Accepted Manuscript updated: January 16, 2015 (version 2)
- Version of Record published: February 5, 2015 (version 3)
Copyright
© 2015, Liu 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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Reliable cell cycle commitment in budding yeast is ensured by signal integration
eLife 4:e03977.
https://doi.org/10.7554/eLife.03977
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