Figure 6
Fine-tuning of the R switch by microRNAs.
(a) Switching behavior of the A model with respect to parameters Γ2′ and α′. For a given value of Γ2′, the equilibrium curve of ϕ is plotted with respect to α′ (purple lines). At the saddle point (vertical lines), the higher stable steady state value of ϕ is the “on” value denoted by ϕ* and the value of α′ is the “off-on” value denoted by α*. The value of ϕ* determines the ensuing state of the cell, whether it will go into quiescence, cell cycle, cancer, or apoptosis. Cell states are indicated by the color of the regions. (b) and (c) The parameter Γ2′ of the A model controls both α* and ϕ*. Fixed parameters: ε = 0.1, κ = 5, Γ1′ = 1. (d) and (g) are similar to (a) except that the analysis was done on the R model and two parameters were considered: ΓE (d) and ΓM (g). The saddle node denotes the switching point (S*, E*), which is analogous to (α*, ϕ*) of (a). (e,f) The parameter ΓE can simultaneously control S* and E*. (h,i) The parameter ΓM controls both S* and E*. The values of the rest of the R model parameters are given in Table 1.
