Dr. Alex Levine
Semiflexible networks with transient cross linkers: Bundling, rheology, ripping, and healing
102 Cardwell Hall
November 10, 2014
Networks of semiflexible filaments, such as those found in the cytoskeleton, may be cross-linked by molecules that can unbind and rebind in different places throughout the network. The structure of such networks is therefore dynamic. It may evolve slowly towards equilibrium, or rearrange itself in response to externally applied stresses. Cross linker mobility leads to new rheological features related to bundling/unbundling of filaments, and new dissipative mechanisms associated with cross linker unbinding.
I present in this talk the results of analytic calculations and numerical simulations exploring the effect of transient cross linkers on the linear rheology and structural evolution of semiflexible networks. I also discuss the fluctuation-induced or Casimir interactions between cross linkers in a semiflexible filament network, and examine how such networks rip and recover under large applied stresses.
Dr. Levine is a Professor in the Department of Chemistry & Biochemistry, Department of Physics & Astronomy, Department of Biomathematics at UCLA and the Director of the Center for Biological Physics.