Wednesday, 22 August, 2007
Mechanics of Bundled Semiflexible Polymer Networks
O. Lieleg, M.M.A.E. Claessens, C. Heussinger, E. Frey, and A.R. Bausch -
Phys. Rev. Lett. 99, 088102 (2007)
While actin bundles are used by living cells for structural fortification, the microscopic origin of the elasticity of bundled networks is not understood. Here, we show that above a critical concentration of the actin binding protein fascin, a solution of actin filaments organizes into a pure network of bundles. While the elasticity of weakly cross-linked networks is dominated by the affine deformation of tubes, the network of bundles can be fully understood in terms of nonaffine bending undulations.