Actin self-assembly and the cellular cytoskeleton

COLL 417

Andrea J. Liu1, Itamar Borukhov2, Ajay Gopinathan1, Kun Chun Lee1, and Jennifer Schwarz1. (1) Dept. of Chemistry and Biochemistry, UCLA, 405 Hilgard Ave, Los Angeles, CA 90095, (2) Department of Materials and Interfaces, The Weizmann Institute of Science, P.B.O. 26, Rehovot, Israel
In the cellular cytoskeleton, linker proteins control the morphology of assemblies of actin filaments. This ability to control structure is crucial to cell motility. There are bundling proteins, which cause filaments to organize into bundles, and crosslinking proteins, that cause filaments to form networks. We will discuss theoretical work aimed at elucidating the important physical parameters that distinguish bundling and crosslinking proteins. The equilibrium phase behavior of charged rods suggest possible mechanisms by which the cell may exploit proximity to an underlying phase transition to control morphology. We will also discuss possible dynamical instabilities that can lead to selection of structures.