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arXiv · 0806.0856

New Proposed Mechanism of Actin-Polymerization-Driven Motility

Kun-Chun Lee·Andrea J. Liu
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Abstract

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.

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Kun-Chun Lee, Andrea J. Liu. 2008-06-06. New Proposed Mechanism of Actin-Polymerization-Driven Motility. https://doi.org/10.1529/biophysj.108.134783

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