Dynamin superfamily proteins are multi-domain mechano-chemical GTPases which are implicated in nucleotide-dependent membrane remodeling events. A prominent feature of these proteins is their assembly-stimulated mechanism of GTP hydrolysis. The molecular basis for this reaction has been initially clarified for the dynamin-related guanylate binding protein 1 (GBP1) and involves the transient dimerization of the GTPase domains in a parallel head-to-head fashion. A catalytic arginine finger from the phosphate binding (P-) loop is repositioned towards the nucleotide of the same molecule to stabilize the transition state of GTP hydrolysis. Dynamin uses a related dimerization-dependent mechanism, but instead of the catalytic arginine, a monovalent cation is involved in catalysis. Still another variation of the GTP hydrolysis mechanism has been revealed for the dynamin-like Irga6 which bears a glycine at the corresponding position in the P-loop. Here, we highlight conserved and divergent features of GTP hydrolysis in dynamin superfamily proteins and show how nucleotide binding and hydrolysis are converted into mechano-chemical movements. We also describe models how the energy of GTP hydrolysis can be harnessed for diverse membrane remodeling events, such as membrane fission or fusion.

中文翻译：

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动力蛋白超家族中 GTP 水解和构象转变的机制

动力蛋白超家族蛋白是涉及核苷酸依赖性膜重塑事件的多域机械化学 GTP 酶。这些蛋白质的一个突出特征是它们的组装刺激 GTP 水解机制。该反应的分子基础已初步阐明了与动力蛋白相关的鸟苷酸结合蛋白 1 (GBP1)，并涉及 GTPase 域以平行头对头方式的瞬时二聚化。来自磷酸盐结合 (P-) 环的催化精氨酸指重新定位到同一分子的核苷酸以稳定 GTP 水解的过渡态。Dynamin 使用相关的二聚化依赖机制，但不是催化精氨酸，而是一价阳离子参与催化。已经揭示了 GTP 水解机制的另一种变体，用于在 P 环中的相应位置带有甘氨酸的动力蛋白样 Irga6。在这里，我们强调了动力蛋白超家族蛋白中 GTP 水解的保守和发散特征，并展示了核苷酸结合和水解如何转化为机械化学运动。我们还描述了如何利用 GTP 水解的能量进行各种膜重塑事件的模型，例如膜裂变或融合。