粉样纤维细胞核的多维视图,以原子的细节
Fahimeh Baftizadeh1, Xevi Biarnes, Fabio Pietrucci
1SISSA , Via Bonomea 265, Trieste, Italy.
Journal of the American Chemical Society
|January 27, 2012
概括
研究人员使用分子动力学模拟了粉样β结构的形成. 他们详细介绍了一条复杂的核化途径,涉及反平行和平行β片,挑战了蛋白质聚合的经典核化理论.
科学领域:
- 生物物理学的生物物理.
- 计算化学计算化学
- 分子生物学分子生物学
背景情况:
- 粉样纤维素与神经退行性疾病有关.
- 了解粉样蛋白形成的初始阶段对于治疗的发展至关重要.
研究的目的:
- 为了阐明粉样β结构的核化路径.
- 描述聚合物形成的自由能源景观.
主要方法:
- 从无序聚合物中模拟了有序粉样β结构的形成,使用明确溶剂中的18个多链.
- 采用了偏差交换元动力学加速的分子动力学.
- 利用8个集体变量来计算数百个聚合结构的自由能量.
主要成果:
- 描述了详细的核化路径,包括初始形成反平行β片,随后出现平行片.
- 确定了一个关键点,在足够形成平行板时,自由能量显著下降.
- 发现复杂的核化途径不能用单个反应坐标的经典核化理论来描述.
结论:
- 粉样纤维的核化是一个复杂的过程,涉及从反平行到平行β-sheet结构的过渡.
- 经典核化理论不足以描述观察到的多面核化途径.
- 这项研究提供了关于蛋白质聚合和纤维细胞形成的早期事件的见解.
相关概念视频
Amyloid Fibrils
Amyloid fibrils are aggregates of misfolded proteins. Under most circumstances, misfolded proteins are either refolded by chaperone proteins or degraded by the proteasome. However, in the case of a mutation or a disease, these proteins can accumulate to form large clusters and often further assemble to form elongated fibers, called fibrils.
Amyloid deposits were observed as early as 1639 in the liver and the spleen. In 1854, Rudolph Virchow performed iodine staining, normally used to...
Amyloid deposits were observed as early as 1639 in the liver and the spleen. In 1854, Rudolph Virchow performed iodine staining, normally used to...
Amyloid Fibrils
Amyloid fibrils are aggregates of misfolded proteins. Under most circumstances, misfolded proteins are either refolded by chaperone proteins or degraded by the proteasome. However, in the case of a mutation or a disease, these proteins can accumulate to form large clusters and often further assemble to form elongated fibers, called fibrils.
Amyloid deposits were observed as early as 1639 in the liver and the spleen. In 1854, Rudolph Virchow performed iodine staining, normally used to...
Amyloid deposits were observed as early as 1639 in the liver and the spleen. In 1854, Rudolph Virchow performed iodine staining, normally used to...
Formation of Intermediate Filaments
Intermediate filaments are cytoskeletal proteins with higher tensile strength and flexibility than microfilaments and microtubules. Unlike the other two cytoskeletal proteins, intermediate filament formation lacks the enzymatic activity to hydrolyze nucleotides like ATP and GTP to generate energy for polymerization. Therefore, the formation of intermediate filaments is multistep self-assembly. The involvement of any accessory proteins in intermediate filament formation has not yet been reported.

