Virginia TechNovak, BelaPataki, Z.Ciliberto, AndreaTyson, John J.2014-04-092014-04-092001-03Novak, B.; Pataki, Z.; Ciliberto, A.; Tyson, J. J., "mathematical model of the cell division cycle of fission yeast," Chaos 11, 277 (2001); http://dx.doi.org/10.1063/1.13457251054-1500http://hdl.handle.net/10919/47057Much is known about the genes and proteins controlling the cell cycle of fission yeast. Can these molecular components be spun together into a consistent mechanism that accounts for the observed behavior of growth and division in fission yeast cells? To answer this question, we propose a mechanism for the control system, convert it into a set of 14 differential and algebraic equations, study these equations by numerical simulation and bifurcation theory, and compare our results to the physiology of wild-type and mutant cells. In wild-type cells, progress through the cell cycle (G1 -->S --> G2 -->M) is related to cyclic progression around a hysteresis loop, driven by cell growth and chromosome alignment on the metaphase plate. However, the control system operates much differently in double-mutant cells, wee1(-) cdc25 Delta, which are defective in progress through the latter half of the cell cycle (G2 and M phases). These cells exhibit "quantized" cycles (interdivision times clustering around 90, 160, and 230 min). We show that these quantized cycles are associated with a supercritical Hopf bifurcation in the mechanism, when the wee1 and cdc25 genes are disabled. (C) 2001 American Institute of Physics.en-USIn Copyrightanaphase-promoting complexp25(rum1) cdk inhibitors-phaseschizosaccharomyces-pombemolecular-modelmitotic inducerg1 phasemitosiskinasecdc2Article - Refereedhttp://scitation.aip.org/content/aip/journal/chaos/11/1/10.1063/1.1345725https://doi.org/10.1063/1.1345725