人类质蛋白的天然变体完全防止了质疾病
Emmanuel A Asante1, Michelle Smidak1, Andrew Grimshaw1
1MRC Prion Unit, Department of Neurodegenerative Disease, UCL Institute of Neurology, London WC1N 3BG, UK.
Nature
|June 11, 2015
概括
G127V蛋白 (PrP) 变体对诸如 kuru 和 Creutzfeldt-Jakob 疾病 (CJD) 等蛋白疾病提供了完全的抵抗力. 这种变异也强烈抑制了其他子菌株的传播.
科学领域:
- 神经退行性疾病的神经退行性疾病
- 子生物学 子生物学
- 进化遗传学的进化遗传学
背景情况:
- 哺乳动物的子是错误折叠的子蛋白 (PrP) 组件,导致致命的神经退行性疾病.
- 在 kuru 流行病期间,G127V PrP 变种在阳性选择下出现,在异构菌中提供保护.
- 该G127V变异仅在M129 PRNP等位基因上发现.
研究的目的:
- 研究G127V PrP变种的保护作用.
- 检查G127V和M129V PrP多态之间的相互作用.
- 确定G127V介导的电阻的机制.
主要方法:
- 转基因小鼠模型表达人类PrP变体 (G127V和野生类型).
- 使用kuru,古典克鲁茨菲尔特-雅各布病 (CJD) 和CJD变体子的感染研究.
- 分析不同PrP表达比的转换和传播.
主要成果:
- 表达G127V和野生类型PrP的转基因小鼠抵抗了kuru和经典CJD子.
- 只有G127V PrP表达的小鼠对所有测试的子菌株都具有抗性.
- G127V PrP对离子转化具有耐火性,并且以剂量依赖的方式抑制野生型离子的传播.
结论:
- 该G127V PrP变种提供强大的,菌株特异性对病的抗性.
- 与M129V多态相比,G127V通过不同的机制提供保护.
- G127V作为子传播的强有力的抑制剂,提供了潜在的治疗标.
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