Figure 4.

Myosin binding preference is dependent on actin orientation and distance between thin and thick filaments

(A) Angular distribution of myosin heads shown by a circular histogram of the orientation of the actin subunits bound by myosin heads. The colors indicate three different thick filaments where the myosin heads originate.

(B) Hotspots of myosin binding from three thick filaments shown on actin filaments. Actin filaments are colored with the footprint of the myosin heads according to multiple sequence alignment of the myosin binding profile sequences determined from the annotated volume and the fitted model in Figure 3B. See also Figure S5. The preferred side on a thin filament for binding of a certain myosin group is shown in the schematic diagram below.

(C) Histograms of distances between thin and thick filaments at actin subunits with (orange) or without (green) a myosin head bound. Mean distances are 25.9 nm (SD 2.7 nm) and 26.3 nm (SD 2.7 nm), respectively. No skewness was measured in either population, meaning both distributions can be considered Gaussian.