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Bifurcation analysis of a model of the budding yeast cell cycle

Dorjsuren Battogtokh·John J. Tyson
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Abstract

We study the bifurcations of a set of nine nonlinear ordinary differential equations that describe the regulation of the cyclin-dependent kinase that triggers DNA synthesis and mitosis in the budding yeast, Saccharomyces cerevisiae. We show that Clb2-dependent kinase exhibits bistability (stable steady states of high or low kinase activity). The transition from low to high Clb2-dependent kinase activity is driven by transient activation of Cln2-dependent kinase, and the reverse transition is driven by transient activation of the Clb2 degradation machinery. We show that a four-variable model retains the main features of the nine-variable model. In a three-variable model exhibiting birhythmicity (two stable oscillatory states), we explore possible effects of extrinsic fluctuations on cell cycle progression.

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Dorjsuren Battogtokh, John J. Tyson. 2004-04-05. Bifurcation analysis of a model of the budding yeast cell cycle. https://doi.org/10.1063/1.1780011

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