病毒进化中的扩散和传播之间的权衡 - - 来自SARS-CoV-2的进化和功能分析的见解
Jui-Hung Tai1,2, Ding-Chin Lee3, Hsin-Fu Lin1
1Graduate Institute of Clinical Medicine, College of Medicine, National Taiwan University, Taipei, 10002, Taiwan.
Virology journal
|April 19, 2025
概括
病毒进化面临着相互矛盾的需求:传播和宿主内部的适应. 根据SARS-CoV-2的数据,突变可以在宿主之间造成损害,这表明多样性驱动多样性和潜在的新变种,如Omicron.
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:
- 病毒需要在宿主之间具有很高的传播能力,以及在宿主内部有效的适应才能取得成功.
- 这些需求与病毒遗传多样性之间的相互作用尚未得到充分理解.
- SARS-CoV-2 (严重急性呼吸系统综合征冠状病毒2) 提供了一个独特的数据集来研究这些进化压力.
研究的目的:
- 研究宿主内部适应对SARS-CoV-2宿主间传播能力的影响.
- 识别由潜在的相互冲突的选择压力形成的遗传变异.
- 探索类型在维护病毒遗传多样性和推动新变异的出现中的作用.
主要方法:
- 从2020年初到2021年中期,分析了大约200万个SARS-CoV-2序列.
- 对宿主内部和宿主之间突变的识别和频率分析.
- 在体外鉴定特定突变的特征,如尖峰M1237I,以评估它们的功能影响.
主要成果:
- 发现宿主内部的高频突变对宿主间的传播有害,这表明反向选择.
- 一个非同义突变的子集,由类型维持,显示显著高于中性预期的频率,没有克隆扩张.
- 尖峰的M1237I突变体现了类型,增强了病毒的组合,但减少了体外传播.
- 这些类变异构成了SARS-CoV-2遗传多样性的很大一部分 (37%),尽管是总变化的很小一部分 (2%).
- 这些突变在Omicron变异中的流行程度表明,类可能会促进积极的表现和成功变异的兴起.
结论:
- 主体内部适应和主体间传播之间的相互冲突的选择压力塑造了SARS-CoV-2的进化.
- 类型在维护病毒遗传多样性方面发挥着至关重要的作用,可能有助于新型变异的出现.
- 目前对病毒群体动态的估计,通常假定宿主内部变异的中立性,可能需要重新评估,因为这些突变的适应性效应.
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