Cell Migration: A Physically Integrated Molecular Process

Integrins receive signals from other receptors that lead to activation of ligand binding (inside-out signaling) and matrix assembly. Upon binding ligands, they also activate intracellular signaling pathways. These signals converse with pathways that are initiated by soluble ligands to regulate cell functions. In this way, cell adhesion is coordinated with other events to orchestrate complex cellular behavior.

We present here a model for how chemical reactions generate protrusive forces by rectifying Brownian motion. This sort of energy transduction drives a number of intracellular processes, including filopodial protrusion, propulsion of the bacterium Listeria, and protein translocation.