Figure 5. Modulation of circuit dynamics.

(a) A bifurcation diagram obtained by solving Eq. 2 (δ=0.01; γ=10) analytically with standard methods ⁵⁰.

(b) Modeling stochastic switching between the OFF and ON cells and their differential growth. See Supplementary Methods for detailed model description (Eqs. S12–S14).

(c) The simulated time series of ON cells percentage in an OFF → ON culture (grey line) and an ON → OFF culture (black line) (α=19 and ϕ=100). The difference between the two (black dotted line) was fitted to a₀exp(−τ/τ_memory) to obtain τ_memory.

(d) The CFP level of ON → OFF cell cultures (black lines, filled squares) eventually converged to that of the OFF → ON cultures (grey lines, open squares) at the twelfth hour.

(e) Simulations predict that decreasing initial percentage of ON cells reduced memory.

(f) ON → OFF cultures (black lines, filled squares) were prepared by mixing varying ratios of ON cultures and OFF cultures (as indicated). Consistent with the model predictions (e), the CFP levels of ON → OFF cultures converged faster to that of the OFF → ON culture (grey line, open squares) with decreasing initial ON culture percentage. Each error bar indicates the standard deviation of three replicates.

(g) The maximal τ_memory is predicted to occur at low α for a low ϕ (=60) and at high α for a high ϕ ( = 90).

(h) Experimental validation of (g). The τ_memory was calculated by using average time series of at least four replicates (Fig. S11).