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Protein Misfolding Cyclic Amplification of Prions
Published on: November 7, 2012
三种酵母子菌株的仅蛋白质传播
Chih-Yen King1, Ruben Diaz-Avalos
1Institute of Molecular Biophysics, Florida State University, Tallahassee, Florida 32306, USA. chihyen@sb.fsu.edu
Nature
|March 19, 2004
概括
这项研究表明,使用酵母模型,子菌株仅含蛋白质. 同一个蛋白质的不同折叠模式编码不同的子菌株信息,传播感染力.
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:
- 子是感染性蛋白质,与神经退行性疾病有关.
- 关键问题仍然是如何从单一蛋白质中产生不同的子菌株以及它们的基本组成.
- 酵母[PSI]基因元素,一个模型子,增强了无意义突变的读透.
研究的目的:
- 为了研究子菌株的纯蛋白质性质.
- 为了确定不同的子菌株是否被相同蛋白质的不同的折叠模式编码.
- 为了在体外证明新生代的普里昂感染力.
主要方法:
- 从酵母中净化Sup35蛋白的传染性纤维聚合物.
- 在实验室中生成使用纯化聚合物作为种子的延长型粉样纤维.
- 电子显微镜和电子衍射分析纤维结构.
- 在酵母宿主中引入体外生成的纤维,以评估传染性.
主要成果:
- 传染性粉样蛋白纤维在体外从纯化的酵母子种子中产生.
- 在试验室生成的纤维在引入酵母时表现出菌株特定的传染性.
- 电子显微镜和衍射证实了纤维的交叉β粉样蛋白结构,与种子一致.
- 在体外生成的纤维的形态与原来的酵母种子是不可区分的.
结论:
- 子菌株确实是纯蛋白质实体.
- 独特的子菌株信息被编码在Sup35蛋白质的不同,自我传播的交叉β折叠模式中.
- 这项研究为子菌株多样性和传播的结构基础提供了有力的证据.
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