通过固态NMR光谱学探测的Y145Stop人类蛋白粉样蛋白纤维的分子间对齐
Jonathan J Helmus1, Krystyna Surewicz, Marcin I Apostol
1Department of Chemistry, The Ohio State University, Columbus, 43210, United States.
Journal of the American Chemical Society
|August 11, 2011
概括
人类质蛋白的Y145Stop突变体形成了粉样纤维,并有一个平行在注册表中的β-sheet核心. 这一发现促进了对蛋白粉样蛋白结构和疾病机制的理解.
科学领域:
- 结构生物学 结构生物学
- 神经退行性疾病 神经退行性疾病
- 生物物理学的生物物理.
背景情况:
- 人类蛋白 (huPrP23-144) 的Y145Stop突变体与PrP脑粉样血管病变有关.
- 这种突变物作为研究粉样蛋白菌株及其分子基础的模型.
- 之前的研究在huPrP23-144粉样纤维中发现了一个紧的,富含β核和一个非结构化的N端.
研究的目的:
- 为了研究huPrP23-144粉样纤维的高阶结构.
- 为了确定粉样核内的β链的分子间对齐.
主要方法:
- 采用了魔力角旋转 (MAS) 固态NMR光谱学.
- 纤维是由同位素标记蛋白质 ((15) N和 (13) C) 的等等分子混合物制备的.
- 分析了分子间相关性和二极合.
主要成果:
- 在2D (15) N-(13) C光谱中的众多分子间相关性表明β表的平行在注册表中的对齐.
- 分子间 (15) N- (((13) CO 和 (15) N- (((13) Cα 双极合提供了链间距的估计.
- 估计的线条间距大约为4.7-4.8 Å,与平行β片相一致.
结论:
- 这项研究毫不含糊地表明,huPrP23-144粉样核中β链的平行在注册表中的对齐.
- 这种结构洞察对于理解蛋白粉样蛋白形成和相关疾病至关重要.
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