Nuclear pore assembly proceeds by an inside-out extrusion of the nuclear envelope
Nuclear pore assembly proceeds by an inside-out extrusion of the nuclear envelope
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DOI：
10.7554/elife.19071
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发表时间：
2016-09-15
期刊：
影响因子：
7.7
通讯作者：
Ellenberg, Jan
中科院分区：
文献类型：
--
作者：
Otsuka, Shotaro;Bui, Khanh Huy;Ellenberg, Jan
核孔复合体（NPC）介导核质通过核膜的运输。NPC如何组装成这种双膜边界仍然是个谜。在这里，我们捕获的时间分期组装中间体相关的活细胞成像与高分辨率电子断层扫描和超分辨率显微镜。中间体是内核膜（INM）的圆顶状外翻，其直径和深度增长，直到它们与平坦的外核膜融合。活的和超分辨荧光显微镜显示分子成熟的中间体，其中最初包含核和细胞质环组件Nup107，只有后来的细胞质丝组件Nup358。EM粒子平均表明，外翻基地是由一个8倍的旋转对称的环结构从一开始就不断增长的蘑菇状密度与变形膜相关联。定量结构分析表明，相间NPC组装收益的INM的一个不对称的由内而外的挤出。
The nuclear pore complex (NPC) mediates nucleocytoplasmic transport through the nuclear envelope. How the NPC assembles into this double membrane boundary has remained enigmatic. Here, we captured temporally staged assembly intermediates by correlating live cell imaging with high-resolution electron tomography and super-resolution microscopy. Intermediates were dome-shaped evaginations of the inner nuclear membrane (INM), that grew in diameter and depth until they fused with the flat outer nuclear membrane. Live and super-resolved fluorescence microscopy revealed the molecular maturation of the intermediates, which initially contained the nuclear and cytoplasmic ring component Nup107, and only later the cytoplasmic filament component Nup358. EM particle averaging showed that the evagination base was surrounded by an 8-fold rotationally symmetric ring structure from the beginning and that a growing mushroom-shaped density was continuously associated with the deforming membrane. Quantitative structural analysis revealed that interphase NPC assembly proceeds by an asymmetric inside-out extrusion of the INM.