超膜β-桶模型的α-Synuclein寡合体
Manuela Maurer1, Themis Lazaridis1
1Department of Chemistry & Biochemistry, City College of New York/CUNY, 160 Convent Ave, New York, New York 10031, United States.
Journal of chemical information and modeling
|November 14, 2023
概括
阿尔法-同核素寡合体可能通过形成跨膜β-桶来损害细胞. 模拟显示这些结构可以插入膜,其稳定性取决于特定的蛋白质区域和质突状态,为神经退行性疾病机制提供了洞察力.
科学领域:
- 结构生物学是结构生物学.
- 神经科学是一个神经科学.
- 生物物理学的生物物理.
背景情况:
- 阿尔法-同核素聚合与帕金森病和多重系统缩有关.
- 阿尔法-同核素寡合体的细胞毒性机制,特别是它们与细胞膜的相互作用,仍然不清楚.
- 目前没有嵌入膜的α-synuclein oligomers的高分辨率结构.
研究的目的:
- 构建和评估由α-synuclein形成的潜在的跨膜β-桶结构.
- 研究这些假定嵌入膜复合物的稳定性和结构动力学.
- 探索特定蛋白质区域 (NAC,35-56) 和丁质突在桶形成和稳定中的作用.
主要方法:
- 序列分析以确定在α-synuclein内潜在的嵌入膜β-hairpin区域.
- 由NAC (64-92) 和35-56区域形成的β-桶的计算建模.
- 分子动力学模拟 (隐含的膜孔和高达10μs的全原子模拟) 来评估桶稳定性和水分.
主要成果:
- 由NAC区域 (64-92) 形成的β-桶显示,在膜内稳定插入和水合超过10μs.
- 由35-56区域形成的β-桶显示稳定插入,但在中性His50条件或His50-to-Q突变下脱水并崩.
- 在35-56桶中对His50残留物的质子化产生了圆形,并保持了至少10微秒的水分.
结论:
- 由α-synuclein形成的跨膜β-桶,特别是NAC区域,可以是稳定的膜嵌入结构.
- 35-56区域桶的稳定性和水分是敏感的histidine质子,表明在疾病病理学中的作用.
- 这些发现提供了对神经退行性疾病中α-synuclein诱导细胞毒性的潜在机制的结构性见解.
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