Fig. 4.

An increase in the basal levels of negative regulators reproduces the response dampening observed under conditions of oxidative stress. Simulations of pathway activation in Model 2 (a) and Model 3 (b) by an acute stimulus were run at different steady state levels of negative regulator (NegReg) molecules. Plots are shown for ‘Activator’ species. Rate constant k1 was set to zero and ‘NegReg’ abundance clamped at 4 different abundances. Stimulus strength = 100.