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In Vitro Analysis of E3 Ubiquitin Ligase Function
Published on: May 14, 2021
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一个HOIP/E2~ubiquitin复合物的结构揭示了RBR E3连接酶机制和调节
Bernhard C Lechtenberg1, Akhil Rajput2, Ruslan Sanishvili3
1NCI-Designated Cancer Center, Sanford Burnham Prebys Medical Discovery Institute, 10901 North Torrey Pines Road, La Jolla, California 92037, USA.
Nature
|January 21, 2016
概括
研究人员发现了活性HOIP RING-between-RING (RBR) E3结合酶的结构. 这一发现阐明了RBR E3链酶在泛素转移中的机制,揭示了类似HECT的过程和新的泛素结合位点.
科学领域:
- 生物化学
- 分子生物学
- 结构生物学
背景情况:
- 它可以调节细胞的信号传递和功能.
- E3 基因酶调解基因转移,而 RING 型 E3 基因酶通常是直接作用的.
- 包括HOIP在内的RING-between-RING (RBR) E3链酶通过形成共价中间体而偏离,类似于HECT类型链酶.
研究的目的:
- 确定完全活跃的人类HOIP RBR E3结合酶与E2~ubiquitin结合物的结构.
- 阐明RBR E3连接酶的作用机制.
主要方法:
- 用X射线结晶学检测活性HOIP RBR E3结合酶的结构.
- 生物化学测定用于研究泛素转移机制.
主要成果:
- 确定了与E2~ubiquitin结合物的完整,完全活跃的人类HOIP RBR E3结合酶的第一个结构.
- 活性HOIP RBR采用独特的形状,以延长的方式结合E2~ubiquitin,对齐催化中心进行ubiquitin转移.
- 在HOIP RBR中,有三种螺旋IBR折叠基因与激活的泛素和额外的调节性泛素分子结合,显示出一种类似于HECT的机制.
结论:
- 该结构为RBR E3联酶催化循环提供了关键的见解.
- 这些发现表明RBR E3连接酶的一般机制与以前理解的RING类型连接酶不同.
- 这项研究阐明了以前未知的RBR E3结合酶的机制.
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