SARS-CoV-2 的突变率在不同部位之间非常可变,并受到序列上下文,基因组区域和RNA结构的影响
Hugh K Haddox1, Georg Angehrn2, Luca Sesta2,3
1Computational Biology Program, Fred Hutchinson Cancer Research Center, Seattle, WA 98102, United States.
Nucleic acids research
|June 12, 2025
概括
SARS-CoV-2 (严重急性呼吸系统综合征冠状病毒2) 呈现出高突变率,具有显著的特定部位变异性. 这种变异性受到序列上下文和RNA结构的影响,揭示了对病毒进化的洞察力.
科学领域:
- 病毒学 病毒学
- 分子生物学分子生物学
- 基因组学就是基因组学.
- 进化生物学 进化生物学
背景情况:
- 包括SARS-CoV-2在内的RNA病毒以高突变率而闻名,推动了快速的进化.
- 病毒基因组中的突变率不均,取决于突变类型和基因组位置.
- 了解特定位点的突变速率变化对于准确建模病毒进化至关重要.
研究的目的:
- 估计SARS-CoV-2中每个突变类型的特定地点同名突变率.
- 调查导致突变率观察到变化的因素.
- 描述突变的适应性影响,并确定强受选择的区域.
主要方法:
- 对数百万个SARS-CoV-2全基因组序列的分析.
- 估计每个位点和突变类型的同名突变率.
- 基于序列上下文,基因组区域和RNA二次结构的突变率变异性的建模.
- 通过比较观察到的与预期的突变频率来估计突变适应性影响.
主要成果:
- 在不同部位的同名突变率中观察到高度的变异性.
- 局部序列上下文,基因组区域和RNA二次结构解释了这种变化的很大一部分.
- 特定的基因组区域显示同名或非编码突变的发生率明显低于预期,这表明独立于蛋白质编码的强烈净化选择.
结论:
- 这项研究详细描述了SARS-CoV-2突变过程在个别地点水平.
- 鉴定的突变模式表明了复杂的进化动态和对病毒基因组起作用的选择压力.
- 这些发现增强了对SARS-CoV-2进化的基本理解,并为定量进化建模提供了信息.
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