Nonlinear dynamics and phase space flows to understand the phase behavior of motor protein motion on antiparallel filaments

Date

Aug 30, 2016

Time

11:00 AM - 12:30 PM

Speaker

Hui-Shun Kuan

Affiliation

University of Colorado

Language

en

Main Topic

Physik

Other Topics

Physik

Host

UB

Description

Motor protein motion on biopolymers can be described by driven diffusive models related to the totally asymmetric exclusion process (TASEP). Inspired by recent experiments on the motion of kinesin-4 motors on antiparallel microtubule overlaps, we develop a model incorporating the TASEP on two antiparallel lanes with binding kinetics and lane switching. We determine the steady-state motor density profiles and phase diagram using phase space flows at the mean-field level. We compared our results to kinetic Monte Carlo simulations. Phases previously identified for the single-filament model occur in the limit of zero switching rate. In addition, lane switching couples the density profiles on the two lanes and can lead to a new phase not possible for a single filament: switching moves motors from the higher density lane to lower density lane, causing local jamming and creating multiple domain walls. We determine the phase diagram of the model and discuss the boundary layer length as a function of bulk motor concentration and motor speed.

Last modified: Aug 30, 2016, 9:36:36 AM