Cell Cycle Control by a Minimal Cdk Network
Figure 6
Robustness of MPF oscillations towards molecular noise in MCN-derived cells.
The stochastic model includes both intrinsic noise (equations in S4 Table) and parametric noise (see Stochastic simulations section). These calculations are done for Ω = 1000, σSMPF = 0.1 and σSRUM1 = 0.25; other parameter values as in Fig. 2. A. MCN strain. B. MCN Δrum1 strain. C. MCN-AF strain (equivalent to MCN Δwee1 Δmik1 strain). In the left panels, we plot, as in previous figures, the time evolution of selected proteins over successive cell cycles, to illustrate the magnitude of stochastic fluctuations observed in our model. In the right panels, we plot histograms of cell size at division in the same format as Fig. 5 in [7]. Black circles with bars correspond to the experimental measurements in [7], while the histograms are the proportions calculated with the mathematical model. The number of cells in each of our samples is 500. All strains carry deletions of the endogenous copies of cdc2, cdc13, cig1, cig2 and puc1.