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arXiv · 1408.6787

Crunching Biofilament Rings

Julien Fierling·Martin Michael Müller·Hervé Mohrbach·Albert Johner·Igor M. Kulić
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Abstract

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.

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Julien Fierling, Martin Michael Müller, Hervé Mohrbach, Albert Johner, Igor M. Kulić. 2014-08-28. Crunching Biofilament Rings. https://doi.org/10.1209/0295-5075%2F107%2F68002

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