洞察与ALS和FTLD相关的四分子DNAG-四复合体:阴离子相互作用和高阶结构的形成
Matja Zalar1, Baifan Wang1, Janez Plavec1,2,3
1Slovenian NMR Center, National Institute of Chemistry, Hajdrihova 19, SI-1000 Ljubljana, Slovenia.
International journal of molecular sciences
|September 9, 2023
概括
在C9orf72中G4C2重复扩张导致ALS/FTLD. 这项研究揭示了和离子如何影响G-四重复结构,影响疾病发展和更高阶复合物形成.
科学领域:
- 生物化学 生物化学
- 分子生物学分子生物学
- 神经遗传学 神经遗传学
背景情况:
- 在C9orf72基因中的G4C2六核酸重复扩张是肌缩侧面硬化症 (ALS) 和前叶退化症 (FTLD) 的主要遗传驱动因素.
- G-四重复形成与这些神经退行性疾病的发病有着内在的联系.
- 是G-四重复结构和稳定性的关键决定因素.
研究的目的:
- 为了研究离子对由G4C2重复形成的G-四重复结构的影响.
- 为了利用15N标记的离子作为K+替代物,对阴离子结合和交换动态进行详细分析.
- 阐明G-四重复形成和更高阶组装的基础结构机制.
主要方法:
- 核磁共振 (NMR) 谱学用于分析G-quadruplex结构和动态.
- 分子动力学 (MD) 模拟用于模拟G-四重复通道内的阴离子相互作用和离子运动.
- 使用15N标记的离子 (15NH4+) 作为探针,检测阴离子结合点和交换通路.
主要成果:
- 单个d(G4C2) 重复形成了一个四分子G-四重复合体,在15NH4+的存在下,在5'-末端有一个全syn四重复合体.
- 15NH4+离子在G-四重复体内的运动由空离子结合点和5'-end全同步四重奏调节.
- 将K+离子添加到与15NH4+结合的G四复合体中,可以通过5'-end G四复合体促进堆叠,形成稳定的高阶结构.
结论:
- 在C9orf72相关的ALS/FTLD中,离子相互作用,特别是与5'-end G-四重奏的相互作用,对于G-四重奏折叠和稳定性至关重要.
- 阴离子结合和交换的动态影响G-四重复的结构转变和潜在聚合.
- 了解这些介质介导的结构机制,可以深入了解疾病的病原和潜在的治疗策略.
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