Figure 6.

Influence of the time of administration of Fgf/Erk inhibitors on cell fate in Nanog^−/− embryos. (A) Scheme of the GRN corresponding to the Nanog^−/− mutant. (B) Proportions of cells maintaining Gata6 expression as a function of the time at which Fgf/Erk inhibitors are administered, simulated by setting va = 0 for all cells of the population. The histogram shows the average values for 10 simulations of the 25-cell model. γ_i is randomly chosen for each cell in the (−10%,+10%) interval. Parameter values and initial conditions are the same as in Fig. 4, with vsn1 = vsn2 = 0. (C) Time evolution of Gata6 simulated for the single-cell model. Cell 1, no inhibitor; cell 2, Fgf/Erk inhibitors administered at t = 1.5; cell 3, Fgf/Erk inhibitors administered at t = 1. (D) Bifurcation diagram of Gata6 as a function of ERK (taken as a control parameter) in the single-cell model (black curves), with the trajectories of the three cells shown in (C) (gray curves).