Parts | Days | Selection | Search | Updates | Downloads | Help
BP: Fachverband Biologische Physik
BP 7: Posters: Statistical Physics in Biological Systems
BP 7.1: Poster
Monday, March 14, 2011, 17:15–20:00, P3
Boundary-induced polarity of random intra-cellular filament networks and vesicle agglomerations — •Philip Greulich1 and Ludger Santen2 — 1University of Edinburgh, Edinburgh, UK — 2Universität des Saarlandes, Saarbrücken
The distribution of nutrients and metabolic products within cells is crucial for cell function. It is performed by active directed transport of vesicles along polarized intracellular filaments, mediated by motor proteins.
We present a model that captures basic features of active vesicle transport on randomly evolving filaments. The filaments form disordered random networks. Filament-filament interactions are neglected and dynamics are homogeneous and isotropic. Due to these symmetries, there is no net bias of filament orientations for periodic boundary conditions. However, symmetry breaking by confining boundary conditions induces a self-organization towards a polarized structure. This occurs despite unbiased dynamics and the absence of external gradients. It leads to a separation and accumulation of vesicle species, following the geometry of the cell volume. The phenomenon can be theoretically understood by using an analogy to Electrostatics. For realistic geometries the model reproduces vesicle agglomerations as can be experimentally observed.