在SARS-CoV中的29核酸删除:ORF8的截断版本正在进行净化选择
Anastassia Bykova1, Andreu Saura1, Galina V Glazko2
1Life Science Research Centre, Faculty of Science, University of Ostrava, Ostrava, 710 00, Czech Republic.
BMC genomics
|July 10, 2023
概括
该研究发现,正如进化分析所指出的那样,SARS-CoV辅助基因ORF8a和ORF8b在功能上很重要. 这一发现与SARS-CoV-2的观察结果是一致的,这表明这些辅助蛋白质的作用是保留的.
科学领域:
- 病毒学 病毒学
- 分子进化分子进化
- 基因组学就是基因组学.
背景情况:
- 辅助蛋白在冠状病毒病原发生过程中起着至关重要的作用.
- 在2003年大流行期间,SARS-CoV的开放阅读框架8 (ORF8) 基因经历了显著的删除,分裂为ORF8a和ORF8b.
- 这种ORF8删除的功能影响在很大程度上仍然不清楚.
研究的目的:
- 为了研究SARS-CoVORF8a和ORF8b基因的进化压力.
- 将ORF8a和ORF8b的选择压力与其他SARS-CoV辅助基因进行比较.
主要方法:
- 对ORF8a和ORF8b基因序列的进化分析.
- 同义和非同义突变率的比较分析.
- 与对其他SARS-CoV辅助基因的选择压力进行比较,例如ORF7a.
主要成果:
- ORF8a和ORF8b都处于净化选择过程中,同义突变的频率高于非同义突变的频率.
- 由ORF8a和ORF8b编码的蛋白质可能具有功能意义.
- ORF8a,ORF8b和ORF7a表现出类似的选择压力,这表明其功能重要性得到保留.
结论:
- 对SARS-CoV的发现证实了SARS-CoV-2中ORF7a-ORF7b-ORF8基因复合体中观察到的高频率删除.
- 这种辅助基因复合体中的频繁删除可能代表着探索有利的蛋白质配置的进化策略.
- 在SARS-CoV的ORF8中固定删除突出了辅助蛋白质进化的潜力,以影响病毒适应.
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