相关实验视频

Updated: May 1, 2026

In Vitro SUMOylation Assay to Study SUMO E3 Ligase Activity

In Vitro SUMOylation Assay to Study SUMO E3 Ligase Activity

Published on: January 29, 2018

通过SUMO-RanGAP1-Ubc9-Nup358复合体揭示了对E3酶活性的洞察力

David Reverter¹, Christopher D Lima

¹Structural Biology Program, Sloan-Kettering Institute, New York, New York 10021, USA.

|June 3, 2005

概括

小型泛素相关修饰剂 (SUMO) 结合调节关键细胞过程. 这项研究揭示了SUMOylation复合物的晶体结构,显示了Nup358/RanBP2如何通过Ubc9.9增强SUMO-1结合.

科学领域:

分子生物学分子生物学
结构生物学结构生物学
生物化学生物化学

背景情况:

后翻译性修改SUMOylation对于调节分化和亡等细胞过程中的蛋白质功能至关重要.
乌比基 (Ub) 和类似于乌比基 (Ubl) 的蛋白质结合涉及E2结合酶和E3结合酶.
Nup358/RanBP2 作为 SUMO E3 酶,将 SUMO 结合的 RanGAP1 定位到与 Ubc9 (SUMO E2) 的核孔复合体.

研究的目的:

阐明SUMOylation通过Nup358/RanBP2 E3结合酶介导的结构基础.
了解Nup358/RanBP2增强SUMO-1对其基质的结合的机制.

主要方法:

用X射线晶体学来确定四个蛋白质复合体的3.0-Å结构 (Ubc9,Nup358/RanBP2 E3酶域和SUMO-1结合的RanGAP1).
使用额外的基质进行生物化学和动力学测试以验证拟议的机制.

主要成果:

晶体结构揭示了Ubc9-Nup358/RanBP2-SUMO-1-RanGAP1复合物的复杂组合.
结构和生化数据支持一个模型,Nup358/RanBP2通过同时结合SUMO-1和Ubc9.9而作为E3结合酶.
这种结合将SUMO-E2二氧化定位为有效的结合.

结论:

Nup358/RanBP2 通过促进 SUMO-1 和 Ubc9 E2 结合酶之间的相互作用,作为 SUMO E3 结合酶起作用.
结构洞察力提供了对E3结合酶如何提高SUMOylation效率的机制性理解.
这项研究阐明了Nup358/RanBP2在核孔综合体中调节SUMOylation中的作用.

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