Figure 3.

Time course showing reversible changes in the sliding movement of an actin filament with repetitive temperature pulses. Displacement of the centroid of the fluorescence image of the actin filament (1.0 μm long) is shown by ○ every 1/30 s. A laser pulse of 0.53-s duration was given every 1.07 s. The temperature was estimated from the average intensity of the actin filament in each frame at 30 frames/s. ● and error bars show the average ± SD for 14 consecutive frames (0.47 s). The coverslip temperature was kept at 18°C ± 1°C.