一个稳定的G发针的结构
Martin Gajarský1, Martina Lenarčič Živković2, Petr Stadlbauer3
1Central European Institute of Technology, Masaryk University , Kamenice 753/5, 62500 Brno, Czech Republic.
Journal of the American Chemical Society
|February 21, 2017
概括
研究人员从酵母端粒DNA中发现了第一个稳定的G-hairpin原子结构. 这种富含G的DNA形成了一种由动态G:G基对稳定的新型折叠结构,揭示了复杂的折叠原理.
科学领域:
- 结构生物学
- 生物化学
- 遗传学
背景情况:
- 富G的DNA序列在端粒中普遍存在,并且可以形成非正规的结构.
- 了解这些结构对于理解端粒维护和基因组稳定至关重要.
- 之前的研究表明,富含G的寡核酸具有复杂的折叠模式.
研究的目的:
- 通过原生酵母DNA序列形成的稳定的G-hairpin的原子分辨率结构.
- 阐明控制富G的寡核酸结构的折叠原理和基配对机制.
- 探索对预测自然DNA结构和设计人工DNA元素的影响.
主要方法:
- 使用X射线结晶学来获得原子分辨率结构.
- 从Saccharomyces cerevisiae端粒DNA中合成了一种11核酸G丰富的寡核酸 (5'-d(GTGTGTG) - 3').
- 进行热力学稳定性分析以评估结构完整性.
主要成果:
- 这项研究报告了从原生DNA序列中稳定的G-hairpin的第一个原子分辨率结构.
- DNA采用一种新的混合平行/反平行折叠结构,由动态G:G基对稳定.
- 结构呈现出复杂的拓结构,其中有中心骨干链反转和3'-to-5'-终端堆叠.
结论:
- 这些发现揭示了富含G的寡核酸折叠的新原理,挑战了关于它们复杂性的先前假设.
- 发现的结构对预测自然DNA识别元素和设计人工元素有影响.
- 这项研究突出了短DNA单链的复杂折叠.
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