Effect of mimicking different mechanisms of miRNA action on translation. Effect of decreasing some model parameters mimicking different mechanisms of miRNA action on translation. Relaxation time here is defined as the latest time at which any chemical species in the model differs from its final steady state by 10% A) and B) correspond to the scenario with "inefficient" initiation, with use of the model parameters proposed in  (k1 = k2 = 2, k3 = 5, k4 = 1, [eIF 4F]0 = 6, [60S]0 = 25, [40S]0 = 100), which gives β = 0.48 < 1. C) and D) correspond to the scenario with "efficient" initiation, with parameters (k1 = 2, k2 = 3, k3 = 50, k4 = 0.1, [eIF 4F]0 = 6, [60S]0 = 25, [40S]0 = 100), which gives β = 7.2 > 1. The absciss value indicates the degree of inhibition (decreasing) of a parameter. E-H) same as A-D) but for a modified cap structure, modeled by reduced k1 parameter: k1 = 0.01 for these curves, the other parameters are the same as on A-D) correspondingly.