个别地点的选择性事件是病毒病毒群的演变的基础
Cristian Molteni1, Diego Forni1, Rachele Cagliani1
1Scientific Institute IRCCS E. MEDEA, Bioinformatics, Via don Luigi Monza, Bosisio Parini 23842, Italy.
Virus evolution
|June 12, 2023
概括
病毒 (MPXV) 进化揭示了核心基因的净化选择和免疫相关基因的积极选择. 目前的疫情血统清除了有害的突变,观察到的有益变化很少.
科学领域:
- 病毒学和进化遗传学
- 人口遗传学 人口遗传学
- 分子生物学分子生物学
背景情况:
- 病毒 (MPXV) 呈现出地理遗传结构,分为I类和II类,具有不同的毒性和宿主关联.
- 2022年全球MPXV疫情主要由与Clade IIb相关的B.1血统主导,该血统携带的突变可能来自阿波利波蛋白B mRNA编辑催化聚类3 (APOBEC3) 活性.
研究的目的:
- 通过人口遗传学和家族遗传学研究历史非洲传播期间的MPXV进化.
- 为了推断健康效应对MPXV基因的分布.
- 分析主要的人类MPXV1 (hMPXV1) B.1血统中的突变和正在进行的疫情变化.
主要方法:
- 应用了种群遗传学-遗传学方法来分析MPXV遗传多样性和进化压力.
- 计算选择系数以推断突变的适应性影响.
- 研究病毒基因进化,专注于那些参与形态发生,复制,转录和宿主免疫相互作用的人.
主要成果:
- 观察到与形态发生,复制和转录相关的基因中的密码体上强烈的净化选择.
- 检测到富含免疫调节和毒性相关基因的积极选择信号,包括那些劫持细胞DNA传感途径的基因.
- 确定了潜在的抗体逃生突变,并推断B.1血统清除了有害的突变,而不是由有益的突变驱动.
结论:
- 在MPXV基因中的积极选择信号表明宿主适应性,并导致Clades I和II之间的毒性差异.
- 主要的B.1爆发谱系已经经历了有害突变的清除,很少发现低频的有益突变.
- 需要进一步的研究来确定观察到的多态突变对正在进行的MPXV进化的意义.
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