Dynamic simulation. Dynamical simulation of the system when dual mechanism and asymmetric deactivation of the receptor are assumed. The dynamics of the protein was complemented with a rate describing de deactivation and break down of the homodimeric protein P*P* ( = k4·P*P*). Figure 7 [a]: Time course for the relevant variables of the system: monomeric activated protein (P*), fully activated receptor (R*R*) and partially activated receptor (R*R). Figure 7 [b]: Time course for single (rSA) and double (rDA) protein activation rates during the simulation. Initial conditions: P(0) = 1.0; P*(0) = 0.0; R*R*(0) = 0:5; R*R(0) = 0.0. Parameter values: k1 = 0.02; k2 = 0 > 05; k3 = 5*k1 = 0.1; k4 = 0.0125; kD1 = kD2 = 0.01.