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arXiv · 0804.0859

Mechanochemical action of the dynamin protein

Martin Lenz·Jacques Prost·Jean-François Joanny
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Abstract

Dynamin is a ubiquitous GTPase that tubulates lipid bilayers and is implicated in many membrane severing processes in eukaryotic cells. Setting the grounds for a better understanding of this biological function, we develop a generalized hydrodynamics description of the conformational change of large dynamin-membrane tubes taking into account GTP consumption as a free energy source. On observable time scales, dissipation is dominated by an effective dynamin/membrane friction and the deformation field of the tube has a simple diffusive behavior, which could be tested experimentally. A more involved, semi-microscopic model yields complete predictions for the dynamics of the tube and possibly accounts for contradictory experimental results concerning its change of conformation as well as for plectonemic supercoiling.

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Martin Lenz, Jacques Prost, Jean-François Joanny. 2008-06-18. Mechanochemical action of the dynamin protein. https://doi.org/10.1103/physreve.78.011911

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