甜菜西黄病毒的机械展开 -1 移信号信号
Katherine H White1, Marek Orzechowski, Dominique Fourmy
1Department of Chemistry and Biochemistry, University of Arizona, Tucson, Arizona 85721, USA.
Journal of the American Chemical Society
|May 24, 2011
概括
离子对于甜菜西黄病毒伪结的稳定性和移效率至关重要. 光学子和模拟揭示了这些离子如何稳定关键结构,解释了病毒突变效应.
科学领域:
- 分子生物学分子生物学
- 生物物理学的生物物理.
- 计算生物学 计算生物学
背景情况:
- 甜菜西黄病毒 (BWYV) 伪结 (PK) 对于病毒复制至关重要.
- 了解BWYV PK的结构动态是开发抗病毒策略的关键.
- 双价离子,特别是Mg2+) 离子在PK稳定性和功能的作用仍然不完全理解.
研究的目的:
- 阐明Mg(2+) 离子在BWYV PK的机械展开阻力中的关键作用.
- 调查Mg(2+) 离子对BWYV PK.介导的-1转移效率的影响.
- 确定Mg2+) 离子稳定PK结构的精确机制.
主要方法:
- 使用光学子 (OT) 的机械展开实验.
- 全原子引导分子动力学 (SMD) 模拟.
- 在不同pH值和核酸序列下分析野生型和突变BWYV PK结构.
主要成果:
- OT和SMD实验证实了干1在PK展开中的关键作用.
- SMD模拟显示,Mg2+) 离子对于稳定干1至关重要,从而影响-1的移.
- 基于离子水化状态,提出了两种不同的Mg2+) 离子介导的稳定干1的机制.
- 这些发现解释了在C8U突变体中观察到的移效率降低.
结论:
- 2+) 离子对于BWYV PK的结构完整性和框架转移功能是不可或缺的.
- 用Mg(2+) 离子稳定干1对于有效的-1核糖体框架转移至关重要.
- 该研究提供了详细的分子层面的了解Mg2+) 离子相互作用在BWYV PK.
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