Tip-to-tip interaction in the crystal packing of PACSIN 2 is important in regulating tubulation activity
Tip-to-tip interaction in the crystal packing of PACSIN 2 is important in regulating tubulation activity
复制标题
DOI：
10.1007/s13238-013-3041-x
复制
发表时间：
2013-09-01
期刊：
影响因子：
21.1
通讯作者：
Zheng, Xiaofeng
中科院分区：
文献类型：
--
作者：
Bai, Xiaoyun;Zheng, Xiaofeng
含有F-BAR结构域的蛋白PACSIN是参与各种膜变形的细胞质磷蛋白，如肌动蛋白重组、囊泡运输和微管运动。我们的前期研究表明，所有的PACSINs都是由两个楔形环组成的新月形二聚体，楔形环介导的相邻二聚体之间的侧向相互作用对蛋白质的包装和蛋白质的活性具有重要意义。在这里，从PACSIN 2的晶体堆积，我们观察到一个紧密的尖端到尖端的相互作用，除了楔环介导的横向相互作用。通过这种头端对头端的相互作用，PACSIN 2的整个包装从顶视图上看显示出具有中心孔的螺旋状组装件。这种尖端到尖端连接的消除抑制了PACSIN 2的微管功能，表明尖端到尖端的相互作用在膜变形活动中起着重要作用。结合我们以前的研究，我们提出了PACSIN 2在膜上组装的包装模型，其中蛋白质通过尖端到尖端和楔环介导的膜表面横向相互作用连接，以产生不同直径的小管。
The F-BAR domain containing proteins PACSINs are cytoplasmic phosphoproteins involved in various membrane deformations, such as actin reorganization, vesicle transport and microtubule movement. Our previous study shows that all PACSINs are composed of crescent shaped dimers with two wedge loops, and the wedge loop-mediated lateral interaction between neighboring dimers is important for protein packing and tubulation activity. Here, from the crystal packing of PACSIN 2, we observed a tight tip-to-tip interaction, in addition to the wedge loop-mediated lateral interaction. With this tip-to-tip interaction, the whole packing of PACSIN 2 shows a spiral-like assembly with a central hole from the top view. Elimination of this tip-to-tip connection inhibited the tubulation function of PACSIN 2, indicating that tip-to-tip interaction plays an important role in membrane deformation activity. Together with our previous study, we proposed a packing model for the assembly of PACSIN 2 on membrane, where the proteins are connected by tip-to-tip and wedge loop-mediated lateral interactions on the surface of membrane to generate various diameter tubules.