Figure 1.

Stochastic single cell behavior. A) Illuminating green fluorescent protein (paGFP) with blue light on a single photoactivatable cell (upper panel) results in paGFP diffusing away from source in a stochastic manner, as shown by the intensity plots (lower panels). Intensity was measured in arbitrary units (AUs). B) Fluorescence levels for four individual cells show stochastic response. Blue circles represent the tumour suppressor protein p53 dynamics and the yellow circles represent the dynamics of ubiquitin E3 ligase MDM2. A, B adopted from [8] and [10], respectively.