在宿主内部与宿主间的SARS-CoV-2进化是由不相关的选择驱动的 - - 进化被挫败了
Mei Hou1, Jingrong Shi2, Zanke Gong1
1State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-sen University, Guangzhou, China.
Molecular biology and evolution
|September 14, 2023
概括
病毒进化涉及两个阶段:宿主内部的扩散和人口竞争. 在这些阶段的敌对选择性力量意味着成功的突变必须首先在宿主瓶中生存,才能成为可传播的SARS-CoV-2变种.
科学领域:
- 病毒学 病毒学
- 进化生物学 进化生物学
- 遗传学 是一个遗传学.
背景情况:
- 病毒进化需要突变首先在宿主中繁殖 (I阶段),然后在更广泛的人群中传播和竞争 (II阶段).
- 了解肠内单核酸变体 (iSNVs) 的动态对于跟踪病毒适应和新菌株的出现至关重要.
研究的目的:
- 分析单个宿主体内的iSNV频率及其随后在SARS-CoV-2更广泛的宿主群体中发生的关系.
- 研究在宿主内复制过程中对病毒突变起作用的选择性力量,以及宿主间传播和竞争.
主要方法:
- 分析了79名感染SARS-CoV-2的患者的iSNVs,这些患者有跟踪传播.
- 宿主内部的iSNV频率的量化 (I阶段) 和宿主间的突变发生 (II阶段).
主要成果:
- 一小部分非同义的iSNV在宿主中达到高频率,但很少在人群中变得普遍.
- 在I阶段 (内宿主) 和II阶段 (间宿主) 的选择性压力往往是无关联的,并且可能是对立的.
- 在第一阶段成功的突变可能缺乏第二阶段所需的传播优势,导致它们的稀有性.
结论:
- 宿主内部进化 (I阶段) 作为一个瓶,可以阻碍或反对长期的病毒进化.
- 成功的病毒变异,包括令人担忧的变异,必须克服肠道内选择才能出现和占主导地位.
- 这些发现强调了考虑宿主内部动态在理解病毒适应和新SARS-CoV-2菌株的出现方面的重要性.
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