Figure 4.

Analysis of ultrafast force-clamp spectroscopy experiments. (A) Fragments of traces corresponding to actin-myosin binding events are shown with different durations under a positive force of 1 pN and [ATP] = 20 μM. Dark gray areas delimit the nearly flat regions found by the PLANT algorithm, corresponding to binding events. White lines represent the reconstructed segments. (B) Histograms show the velocity of the fragments before (gray bars) and after (open bars) threshold-based classification. The dashed black line corresponds to the threshold value. (C) Cumulative histograms show the duration of actin-myosin binding events (gray) and the corresponding fit using a two-exponential cumulative probability density function (black line).