Crunching biofilament rings
1 Institut Charles Sadron, CNRS-UdS - 23 Rue du Loess, BP 84047, 67034 Strasbourg cedex 2, France
2 Equipe BioPhysStat, LCP- A2MC, Université de Lorraine - 1 boulevard Arago, 57070 Metz, France
Received: 2 July 2014
Accepted: 27 August 2014
We discuss a curious example for the collective mechanical behavior of coupled non-linear monomer units entrapped in a circular filament. Within a simple model we elucidate how multistability of monomer units and exponentially large degeneracy of the filament's ground state emerge as a collective feature of the closed filament. Surprisingly, increasing the monomer frustration, i.e., the bending prestrain within the circular filament, leads to a conformational softening of the system. The phenomenon, that we term polymorphic crunching, is discussed and applied to a possible scenario for membrane tube deformation by switchable dynamin or FtsZ filaments. We find an important role of cooperative inter-unit interaction for efficient ring-induced membrane fission.
PACS: 82.35.Pq – Biopolymers, biopolymerization / 87.16.Ka – Filaments, microtubules, their networks, and supramolecular assemblies
© EPLA, 2014