Influence of cargo size on Ran and energy requirements for nuclear protein import
Influence of cargo size on Ran and energy requirements for nuclear protein import
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DOI：
10.1083/jcb.200204163
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发表时间：
2002-10-14
影响因子：
7.8
通讯作者：
Gerace, L
中科院分区：
文献类型：
--
作者：
Lyman, SK;Guan, TL;Gerace, L
以前的工作表明，一些小的蛋白质货物通过核孔复合物（NPC）的运输可以在体外发生在没有核苷三磷酸水解的情况下。我们现在证明，在importin α/β和transportin进口途径，大蛋白质的有效的体外运输，与较小的蛋白质相反，需要水解GTP和小GTP酶Ran。形态学和生物化学分析表明，Ran和GTP的存在允许大货物有效地穿过NPC的中心区域。我们进一步证明，RanGTP的这一功能至少部分涉及其直接结合importin P和transportin。我们认为，RanGTP功能在这些途径，以促进运输的大型货物，提高能力的进口复合物穿越扩散限制区的NPC。
Previous work has shown that the transport of some small protein cargoes through the nuclear pore complex (NPC) can occur in vitro in the absence of nucleoside triphosphate hydrolysis. We now demonstrate that in the importin alpha/beta and transportin import pathways, efficient in vitro transport of large proteins, in contrast to smaller proteins, requires hydrolyzable GTP and the small GTpase Ran. Morphological and biochemical analysis indicates that the presence of Ran and GTP allows large cargo to efficiently cross central regions of the NPC. We further demonstrate that this function of RanGTP at least partly involves its direct binding to importin P and transportin. We suggest that RanGTP functions in these pathways to promote the transport of large cargo by enhancing the ability of import complexes to traverse diffusionally restricted areas of the NPC.