在RanBP2,SUMO1-RanGAP1,E2 Ubc9,Crm1和Ran GTPase之间的核素出口复合物的结构基础
Vladimir Baytshtok1, Michael A DiMattia1,2, Christopher D Lima3,4
1Structural Biology Program, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center, 1275 York Ave, New York, NY, USA.
Nature communications
|July 10, 2025
概括
这项研究揭示了核孔蛋白RanBP2如何与SUMO1修饰的RanGAP1和Ubc9.9相互作用. 这些相互作用对核运输和线粒细胞的进展至关重要,正如冷-EM结构所示.
科学领域:
- 细胞生物学 细胞生物学
- 分子生物学分子生物学
- 结构生物学 结构生物学
背景情况:
- 兰BP2/Nup358是一种关键的核,参与核运输.
- 它与核孔复合体 (NPC) 的SUMO1-修饰的RanGAP1和Ubc9相互作用.
- 这个综合体促进出口和出口的拆卸在Crm1/Ran (GTP) /货物综合体中.
研究的目的:
- 解决RanBP2 C终端碎片与Crm1,SUMO1-RanGAP1/Ubc9和Ran(GTP复合的冷EM结构.
- 阐明RanBP2与Crm1相互作用的结构基础及其在核运输和核分裂中的作用.
主要方法:
- 低温电子显微镜 (cryo-EM) 用于确定高分辨率结构.
- 生物化学测试以验证结构发现.
- 细胞局部化研究,以评估关键相互作用的功能.
主要成果:
- 冷-EM结构揭示了RanBP2,Crm1,SUMO1-RanGAP1/Ubc9和Ran(GTP之间的详细相互作用.
- 在Crm1交互界面中确定了RanGAP1的核出口信号 (NES).
- 删除RanGAP1 NES导致RanGAP1和Ran GTPase在细胞中的错位.
结论:
- 兰BP2的SUMO E3结合酶活性取决于Crm1,RanGAP1 NES和Ran GTPase循环.
- 这些发现支持RanBP2通过调节的相互作用促进核出口和线粒细胞进展的模型.
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