Zipping mechanism for force generation by growing filament bundlesT. Kühne1, R. Lipowsky1 and J. Kierfeld1, 2
1 Max Planck Institute of Colloids and Interfaces - Science Park Golm, 14424 Potsdam, Germany, EU
2 Physics Department, TU Dortmund University - 44221 Dortmund, Germany, EU
received 19 January 2009; accepted in final form 2 June 2009; published June 2009
published online 9 July 2009
We investigate the force generation by polymerizing bundles of filaments, which form because of short-range attractive filament interactions. We show that bundles can generate forces by a zipping mechanism, which is not limited by buckling and operates in the fully buckled state. The critical zipping force, i.e. the maximal force that a bundle can generate, is given by the adhesive energy gained during bundle formation. For opposing forces larger than the critical zipping force, bundles undergo a force-induced unbinding transition. For larger bundles, the critical zipping force depends on the initial configuration of the bundles. Our results are corroborated by Monte Carlo simulations.
87.16.Ka - Filaments, microtubules, their networks, and supramolecular assemblies.
87.16.A- - Theory, modeling, and simulations.
87.15.rp - Polymerization.
© EPLA 2009