使用定向动态曲调节RNA对齐:使用NMR残留双极合器确定头发针的原子分辨率组合的应用
Loïc Salmon1, George M Giambaşu2, Evgenia N Nikolova3
1Department of Molecular, Cellular, and Developmental Biology and Howard Hughes Medical Institute, University of Michigan , Ann Arbor, Michigan 48109, United States.
Journal of the American Chemical Society
|August 27, 2015
概括
研究人员开发了一种新方法来对准核酸以进行更好的分子动力学模拟. 这种方法提高了原子分辨率集的精度,揭示了RNA动态和结构灵活性.
科学领域:
- 生物物理
- 计算生物学
- 结构生物学
背景情况:
- 确定生物分子的原子分辨率集需要大量的实验数据.
- 核磁共振 (NMR) 余极合 (RDC) 提供了有价值的动态信息,但受到调节核酸对齐的挑战的限制.
研究的目的:
- 通过终端螺旋的可变动态扭曲来调节RNA对齐的新策略.
- 测试分子动力学 (MD) 模拟的准确性,并确定RNA的原子分辨率.
- 在原子分辨率下描述RNA动态.
主要方法:
- 在终端螺旋体中引入可变的动态扭曲以调节RNA对齐.
- 在cUUCGg圆环中测量了七组RDC.
- 使用珀ff10力场进行0.8μs的MD模拟.
- 从MD模拟中选择了一个子集,以匹配实验RDC.
- 获得的NMR旋转放松数据,包括R ((1ρ) 放松分散.
主要成果:
- 由MD生成的集合量化地复制了测量的RDC,但为了准确的协议,需要选择子集合.
- 在RDC选择和MD组合之间的差异在灵活的循环区域和连接的骨干角度中最为突出.
- 与MD组合相比,RDC选择的组合表现出更为统一的动态.
- 核磁共振回旋放松数据证实了RNA的ps-ns时间表动态.
- 满足RDC的组合包括在晶体结构中观察到的形状,这表明RNA形状适应的内在可塑性.
结论:
- 开发的策略有效调节RNA对齐,使原子分辨率组合能够更准确地确定.
- 这项研究验证了MD模拟用于表征RNA动态,需要进行子集选择以获得高精度.
- 这种方法对于测试核酸力场和理解原子分辨率下各种RNA动态是有价值的.
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