Figure 6.

Combinatory effects of intrinsic noise (IN), extrinsic colored noise (CN) and cellular heterogeneity (CH) on the variability in oscillation. The influence of the CN alone, CN and IN, CN and CH, and three sources together on the amplitude (a), width (b), period (c) of p53 pulses and p53-Mdm2 delay (d). The dotted lines denote the estimates of CV. Parameters are set as follows: D = 0.1 for CN, Ω = 10² for IN, and S = 0.1 for CH. In each case, 1000 runs of stochastic simulations lasting 3000 min are performed. In the presence of CH, a set of parameter values is sampled for each simulation. The CN is only added to the process of gene transcription. The axis of τ is on logarithmic scale.