Lenz Martin, Prost Jacques, Joanny Jean-François
Institut Curie, Centre de Recherche, Laboratoire Physico-Chimie Curie, Paris F-75248, France.
Phys Rev E Stat Nonlin Soft Matter Phys. 2008 Jul;78(1 Pt 1):011911. doi: 10.1103/PhysRevE.78.011911. Epub 2008 Jul 21.
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, semimicroscopic 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.
发动蛋白是一种普遍存在的GTP酶，它能使脂质双层形成管状，并且参与真核细胞中的许多膜切断过程。为了更好地理解这种生物学功能，我们开发了一种广义流体动力学描述，用于描述大型发动蛋白 - 膜管的构象变化，同时将GTP消耗视为自由能来源。在可观测的时间尺度上，耗散主要由有效的发动蛋白 - 膜摩擦力主导，并且管的变形场具有简单的扩散行为，这可以通过实验进行验证。一个更复杂的半微观模型对管的动力学给出了完整的预测，并且可能解释了关于其构象变化以及麻花状超螺旋的相互矛盾的实验结果。
