Fig. 6.

Processive myosin movement is observed under confinement in the flow-cell CLIC device. (a) Interferometry of and least-squares fit to the CLIC imaging chamber height profile. The first two labeled interference minima (blue rings) correspond to heights of 184 nm and 368 nm respectively. (b) Two example kymographs of myosin proteins imaged in the chamber at heights of ~80 nm. (c) Distribution of the number of myosins exhibiting processive motion as a function of chamber height, normalized by area. Error bars represent the expected standard deviation assuming Poissonian counting statistics. (d) Scatter plot of processive motor speed vs. chamber height. The speed shows little correlation with chamber height, indicating that confinement does not significantly perturb the motor behavior at heights where motors continue to walk.