单分子光揭示了多域蛋白中的序列特异性错折
Madeleine B Borgia1, Alessandro Borgia, Robert B Best
1University of Cambridge Chemical Laboratory, Lensfield Road, Cambridge CB2 1EW, UK.
Nature
|May 31, 2011
概括
与疾病相关的蛋白质错折,可以通过在多域蛋白中保持域间的低序列相同性来避免. 这项研究量化了错误折叠事件,并证实了序列多样化作为预防蛋白质错误折叠的进化策略.
科学领域:
- 生物化学 生物化学
- 结构生物学 结构生物学
- 分子生物学分子生物学
背景情况:
- 蛋白质错误折叠与许多衰弱性疾病有关.
- 多域蛋白质占真核蛋白质组的75%,但防止域间错误折叠的机制尚不清楚.
- 假设链接域之间的低序列相同性是为了防止错误折叠.
研究的目的:
- 来自titin的协同免疫球蛋白域中调查域间错误折叠事件.
- 为了量化错误折叠的蛋白质状态的稳定性.
- 确定序列识别在防止蛋白质错折的作用.
主要方法:
- 单分子Förster共振能量转移 (smFRET) 用于检测和量化体外错误折叠事件.
- 在本地条件下分析了具有不同序列身份的双联免疫球蛋白域.
- 使用粗粒度分子模拟来建模错折结构.
主要成果:
- 在体外重新折叠过程中,大约5.5%的相同域分子错误折叠,形成稳定的错误折叠状态.
- 配对域具有42%的序列身份表现出错折叠,而那些具有24%的序列身份则没有.
- 分子模拟预测了域互换结构,与实验smFRET数据一致.
结论:
- 蛋白质错误折叠涉及特定的,依赖序列的域交换机制.
- 邻近域之间的序列同一性的多样化是一种有效的进化策略,以防止多域蛋白质的错误折叠.
- 了解这些机制对于解决与蛋白质错折相关的疾病至关重要.
相关概念视频
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