Exploration of model parameters to explain the observed stochastic gene expression for six cellular clones. (A) Relationship between normalized variance (NV) and mean fluorescence intensity (MFI) for six cellular clones (C1 to C17) stably transfected with a unique copy of the fluorescent reporter mCherry that was integrated at a different locus in each clone. Black line shows the relationship NV = 1/MFI. (B) Distributions of the possible chromatin dynamics. For each clone, all 1,087 possible couples of (1/k
) values were plotted, expressed as mean open time (1/k
) and mean closed time (1/k
) for all transcription-translation parameter sets explored analytically in the two-state model (see Methods). One dot therefore represents one possible analytical solution for that clone. h, hours; d, days; m, months.