BMC Biophysics

tracked for impact factor

Open Access Letter

Bistability in the actin cortex

Carsten Beta

Author Affiliations

Institut für Physik und Astronomie, Universität Potsdam, 14476 Potsdam, Germany

Max-Planck-Institut für Dynamik and Selbstorganisation, 37073 Göttingen, Germany

PMC Biophysics 2010, 3:12 doi:10.1186/1757-5036-3-12

Published: 24 June 2010

Abstract

Multi-color fluorescence imaging experiments of wave forming Dictyostelium cells have revealed that actin waves separate two domains of the cell cortex that differ in their actin structure and phosphoinositide composition. We propose a bistable model of actin dynamics to account for these experimental observation. The model is based on the simplifying assumption that the actin cytoskeleton is composed of two distinct network types, a dendritic and a bundled network. The two structurally different states that were observed in experiments correspond to the stable fixed points in the bistable regime of this model. Each fixed point is dominated by one of the two network types. The experimentally observed actin waves can be considered as trigger waves that propagate transitions between the two stable fixed points.

PACS Codes: 87.16.Ln, 87.17.Aa, 89.75.Fb