由结构研究揭示的在无素受体hRpn13中的一个自适应性结位
Bakar Hassan1, Monika Chandravanshi1, Martin Y Ng2
1Protein Processing Section, Center for Structural Biology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Frederick, MD, USA.
Nature communications
|July 2, 2025
概括
在hRpn13中的泛素 (Pru) 域的普雷克斯特林类受体结合了泛素和乱的基质序列. 这种双重结合机制对于基质转移到蛋白酶ATPases至关重要.
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:
- 蛋白质hRpn13包含一个类似于pleckstrin的受体,用于ubiquitin (Pru) 域.
- 众所周知,这种Pru域与全方位素和蛋白质酶子单元hRpn2.2相互作用.
研究的目的:
- 阐明hRpn13的Pru域及其绑定伙伴之间的相互作用的结构基础.
- 为了研究hRpn13与ubiquitinated基质的拟议的双酸相互作用模型.
主要方法:
- 通过X射线晶体学,确定Pru与hRpn13.的极端N端 (ENT) 结合的结构.
- 分子动力学模拟以评估ENT:Pru相互作用的稳定性.
- 溶液核磁共振 (NMR) 光谱学用于研究结合亲和力和动态.
主要成果:
- 晶体结构显示,ENT采用U形,本地序列与Pru W108中心的口袋相互作用,非本地序列形成格子相互作用.
- 分子动力学模拟证实了ENT:Pru相互作用的稳定性.
- 核磁共振研究显示,Pru与各种的结合较弱,与乌比奎丁的同时结合,以及hRpn2.2对ENT的取代.
结论:
- hRpn13可以通过双基相互作用参与到无处不在的基质中,结合到无处不在的链和无序的基质序列.
- 与hRpn2的相互作用对于调解基质转移到蛋白酶ATPases至关重要,突出显示了蛋白质降解中的关键调节步骤.
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