Biophysics Letter

European Biophysics Journal

, Volume 37, Issue 8, pp 1361-1366

Open Access This content is freely available online to anyone, anywhere at any time.

Non-Gaussian curvature distribution of actin-propelled biomimetic colloid trajectories

  • Stephan SchmidtAffiliated withDepartment of Physical Chemistry II, University of Bayreuth
  • , Jasper van der GuchtAffiliated withLaboratory of Physical Chemistry and Colloid Science, Wageningen University
  • , P. Maarten BiesheuvelAffiliated withMax Planck Institute of Colloids and Interfaces
  • , Richard WeinkamerAffiliated withMax Planck Institute of Colloids and Interfaces
  • , Emmanuèle HelferAffiliated withLaboratoire d’Enzymologie et Biochimie Structurales, CNRS
  • , Andreas FeryAffiliated withDepartment of Physical Chemistry II, University of Bayreuth Email author 

Abstract

We analyze the motion of colloids propelled by a comet-like tail of polymerizing actin filaments. The curvature of the particle trajectories deviates strongly from a Gaussian distribution, implying that the underlying microscopic processes are fluctuating in a non-independent manner. Trajectories for beads of different size all showed the same non-Gaussian behavior, while the mean curvature decreased weakly with size. A stochastic simulation that includes nucleation, force-dependent dissociation, growth, and capping of filaments, shows that the non-Gaussian curvature distribution can be explained by a positive feedback mechanism in which attached chains under higher tension are more likely to snap.

Keywords

Actin Propulsion Trajectory analysis Stochastic simulation