We present the first numerical simulation of actin-driven propulsion by
elastic filaments. Specifically, we use a Brownian dynamics formulation of the
dendritic nucleation model of actin-driven propulsion. We show that the model
leads to a self-assembled network that exerts forces on a disk and pushes it
with an average speed. This simulation approach is the first to observe a speed
that varies non-monotonically with the concentration of branching proteins
(Arp2/3), capping protein and depolymerization rate (ADF), in accord with
experimental observations. Our results suggest a new interpretation of the
origin of motility that can be tested readily by experiment.Comment: 31 pages, 5 figure