Figure 6.

Nonlinear dependence of filament motility on motor-filament interaction probability. (A) Shown here is the trajectory of a filament for ρ_m = 4 μm⁻² and L = 15 μm as a function of time for different values of the duty ratio, r_D. Depth of color indicates time of the snapshot, as indicated by the scale. The blue circles mark the barbed ends. (B) Given here is the filament speed decomposed into longitudinal (filled symbols) and transverse (open symbols) components as a function of the dimensionless parameter $\mathcal{M}$ = ρ_ml_mLr_D, by independently varying ρ_m (green squares), L (red diamonds), and r_D (blue circles). The default parameters were ρ_m = 4 μm⁻², L = 15 μm, and r_D = 0.5. (C) Shown here is the mean squared displacement for various values of $\mathcal{M}$. The blue dashed line shows diffusive behavior and the orange dashed line shows ballistic behavior. (D) Given here is the path persistence length for simulations described in (B), evaluated via Eq. 9 over five replicates. The lines are theoretical predictions for these values using Eqs. 1–6 in Duke et al. (54). The red dashed line is for increasing L, the blue dotted line is for increasing r_D, and the green solid line is for increasing ρ_m. To see this figure in color, go online.