Figure 2 of Rotov, Mol Vis 2017; 23:416-430.

Figure 2. Time course of the production of active transducin (T*) and phosphodiesterase (PDE*) (modified from [1-3]). Times from t0 to t6 represent the durations of corresponding transitions in Figure 1 (state 0 to state 1, state 1 to state 2, etc.). The straight line initiating from t4 shows the time course of T* production, at the rate of νRG. The first PDE* would ideally appear at t6. The bent red line shows a more realistic approximation that may result from the extra delay between T*–PDE binding and activation of PDE. νRE is the steady rate of PDE* production achieved after an effective delay teff. In accordance with [3], we further assume νRE = νRG. td > t6 is placed, rather arbitrarily, as the delay time when the minimum deviation of PDE* from its dark level can be detected.