最具传染性的蛋白颗粒是最具传染性的
Jay R Silveira1, Gregory J Raymond, Andrew G Hughson
1Laboratory of Persistent Viral Diseases, Rocky Mountain Laboratories, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, Montana 59840, USA.
Nature
|September 9, 2005
概括
较小的蛋白质聚合物,而不是大型纤维,是传染性海绵状脑病变 (TSEs) 的主要驱动因素. 含有PrP的非纤维颗粒显示出最高的传染性和致病潜力.
科学领域:
- 神经生物学 神经生物学 神经生物学
- 蛋白质错误折叠疾病 蛋白质错误折叠疾病
- 子生物学 子生物学
背景情况:
- 像阿尔茨海默氏症和帕金森症这样的神经退行性疾病涉及异常的蛋白质沉积.
- 传染性海绵状脑病变 (TSEs) 的特征是具有抗蛋白酶的蛋白 (PrP(res)) 聚合物.
- 在TSE中确切的致病物种 (纤维素与寡聚体) 仍在争论中.
研究的目的:
- 调查 PrP 聚合物的大小与它们的传染性和转化活性之间的关系.
- 为了确定较小的寡合体或较大的纤维是否是TSE病原体的主要原因.
- 为了描述负责TSE传播的PrP(res) 聚合物的特定尺寸范围.
主要方法:
- 部分分解 PrP () 聚合物的部分分离.
- 使用染色学对PrP(res) 聚合物的尺寸分化.
- 使用光散射和非变质凝电泳,分析聚合物大小,感染力和蛋白质转化活性.
主要成果:
- 传染性和转化活性在17-27 nm (300-600 kDa) 的非纤维 PrP 颗粒中达到顶峰.
- 与这些较小的颗粒相比,大型纤维的活性明显较低.
- 由少于或等于5个PrP分子组成的寡合体几乎没有传染性或转化活性.
结论:
- 非纤维状PrP分子,相当于14-28个蛋白质分子,是TSE疾病的最强有力的发起者.
- 这些发现挑战了大型粉样纤维素是TSE病原体的唯一或主要罪祸首的观点.
- 该研究确定了特定的聚合物大小作为理解和潜在治疗病的关键目标.
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