相关实验视频
Updated: Jul 16, 2025
06:06
In Vitro Analysis of E3 Ubiquitin Ligase Function
Published on: May 14, 2021
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时间解析的冷EM (TR-EM) 分析,通过RING E3形相促进复合体/环体 (APC/C) 进行基质聚化
Tatyana Bodrug1,2, Kaeli A Welsh2, Derek L Bolhuis1,2
1Department of Biochemistry and Biophysics and Lineberger Comprehensive Cancer Center, University of North Carolina, Chapel Hill, NC, USA.
Nature structural & molecular biology
|September 22, 2023
概括
研究人员可视化了亚纳酶促进复合体/循环体 (APC/C) 如何构建聚比基链. 这提供了一个模型,介绍了ubiquitin结合酶如何产生蛋白质体降解信号,这对于细胞过程至关重要.
科学领域:
- 生物化学 生物化学
- 分子生物学分子生物学
- 结构生物学 结构生物学
背景情况:
- 基质聚基因化对于细胞周期调节,细胞亡和免疫反应等关键细胞过程至关重要.
- 由于中间体的短暂性质,了解聚比化动态机制一直是具有挑战性的,通常需要人工稳定.
- 精确的机制,通过E3无素连接酶组装多素链,特别是正规的四个或更多的无素信号为proteasomal降解,仍然在很大程度上是未知的.
研究的目的:
- 阐明由亚纳酶促进复合体/环体 (APC/C) 进行基质聚基化的动态机制.
- 想象Ubiquitin链形成过程中E3结合酶,E2共酶和基质之间的直接相互作用.
- 为了建模E3链酶,特别是APC/C,如何构建蛋白质体降解信号.
主要方法:
- 时间分辨率低温电子显微镜 (cryo-EM) 用于捕获APC/C的快照.
- 基于神经网络的方法CryoDRGN被用来从冷EM数据中重建结构动态.
- 这项研究的重点是人类的APC/C复合体及其相关的E2共酶,UBE2C/UBCH10和UBE2S.
主要成果:
- 在polyubiquitination过程中重建人类APC/C的形状景观.
- 活跃的E3-E2酶对修改基质的直接可视化.
- 发现新生泛素链与APC/C机制之间的新型相互作用,包括其协活性剂CDH1.
- 证明使用新生的泛素链进行修改可以增强过程性多聚素化.
结论:
- 这项研究提供了前所未有的机械洞察力,了解APC/C如何构建聚比基链.
- 提出了一个模型,说明如何通过增强的多素化,无素化酶产生蛋白质体降解信号.
- 这些发现提升了我们对乌比奎信号传递及其在基本细胞过程中的作用的理解.
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