FIGURE 10.

Theoretical contribution of the myosin motor on the channel release model. (A) Rebound of open probability after a negative step (p_O) as a function of the duration of the step in the presence (black lines) and absence (red lines) of the myosin motor. The envelope of the rebound is an indicator of the adaptation process, which is little affected by removal of the myosin. (B) Effects of a positive 0.5-nN adapting step on the response onsets in the presence (black) and absence (red) of myosin. Note that lack of myosin does not affect the fast-adaptation time constant for small stimuli. The bundle displacement is 140 nm. (C) p_O-X relationships under control conditions (solid circles) and after the 0.5-nN adapting step (open circles) in the presence (black) and absence (red) of myosin. The shift in the p_O-X relationship is 110 nm. In these simulations, the rate constant for myosin-driven adaptation, k_A, was 0.05 nm·ms⁻¹·pN⁻¹.