Dynamic Interaction of Amphiphysin with N-WASP Regulates Actin Assembly
Dynamic Interaction of Amphiphysin with N-WASP Regulates Actin Assembly
复制标题
DOI：
10.1074/jbc.m109.064204
复制
发表时间：
2009-12-04
影响因子：
4.8
通讯作者：
Takei, Kohji
中科院分区：
文献类型：
--
作者：
Yamada, Hiroshi;Padilla-Parra, Sergi;Takei, Kohji
两栖素1是一种内吞接头，集中在连接网格蛋白介导的内吞作用和动力蛋白依赖的裂变的突触上，也被证明在肌动蛋白动力学中具有调节作用。在这里，我们报道了两栖素1与N-WASP相互作用并刺激N-WASP和arp2 /3依赖性肌动蛋白聚合。Src同源性和N-BAR结构域都是这种刺激所必需的。酸脂质体引发的N-WASP依赖的肌动蛋白聚合在两栖素1敲除小鼠的脑细胞质中严重受损。在Sertoli细胞中，内源性表达的amphiphysin 1与N-WASP在外周褶边共定位，FRET-FLIM分析证实了这两种蛋白在体内的相关性。这种关联经过调节，并通过用含磷脂酰丝氨酸脂质体刺激细胞表面的磷脂酰丝氨酸受体而增强，从而触发皱褶的形成。这些结果表明，肌动蛋白调控是amphiphysin 1的关键功能，并且该功能与内吞反应过程中该蛋白的内吞接头作用和膜形成/曲率传感特性协同作用。
Amphiphysin 1, an endocytic adaptor concentrated at synapses that couples clathrin-mediated endocytosis to dynamin-dependent fission, was also shown to have a regulatory role in actin dynamics. Here, we report that amphiphysin 1 interacts with N-WASP and stimulates N-WASP- and Arp2/3-dependent actin polymerization. Both the Src homology 3 and the N-BAR domains are required for this stimulation. Acidicliposome-triggered, N-WASP dependent actin polymerization is strongly impaired in brain cytosol of amphiphysin 1 knock-out mice. FRET-FLIM analysis of Sertoli cells, where endogenously expressed amphiphysin 1 co-localizes with N-WASP in peripheral ruffles, confirmed the association between the two proteins in vivo. This association undergoes regulation and is enhanced by stimulating phosphatidylserine receptors on the cell surface with phosphatidylserine-containing liposomes that trigger ruffle formation. These results indicate that actin regulation is a key function of amphiphysin 1 and that such function cooperates with the endocytic adaptor role and membrane shaping/curvature sensing properties of the protein during the endocytic reaction.