Fig. 3.

Stress buildup in bundles with nonidentical motors. (a) In a bundle with motors having nonidentical velocities (shades of gray), filaments of lengths ≈ ℓ_f are subjected to random motor forces at points ≈ ℓ₀ apart distributed throughout their length. (b) Prior to contraction, the environment of a filament of interest (red, delimited by dotted lines) can be approximated by a collection of evenly spaced motors (shades of gray).