Elasticity of Stiff Biopolymer Networks
Abstract
The elasticity of cells is governed by the cytoskeleton, a partially crosslinked network of relatively stiff filaments forming a several 100 nm thick shell called the actin cortex. While the statistical properties of single cytoskeletal filaments are by now relatively well understood [1], theoretical concepts for the elasticity of stiff polymer networks are still evolving. One major open question is to understand how stresses and strains are transmitted in such networks. As a idealized model system we study the elasticity of a two-dimensional random network of rigid rods ("Mikado model")[2]. The essential features incorporated into the model are the anisotropic elasticity of the rods and the random geometry of the network. We show that there are three distinct scaling regimes, characterized by two distinct length scales on the elastic backbone. In addition to a critical rigidiy percolation region and a homogeneously elastic regime we find a novel intermediate scaling regime, where the elasticity is dominated by bending deformations. We discuss the application of these results to F-Actin and microtubule networks. [1] L. Le Goff, O. Hallatschek, E. Frey, F. Amblard, Phys. Rev. Lett. 89, 258101 (2002). [2] J. Wilhelm, and E. Frey, Phys. Rev. Lett. 91, 108103 (2003).
- Publication:
-
APS March Meeting Abstracts
- Pub Date:
- March 2004
- Bibcode:
- 2004APS..MAR.D8010W