自然选择影响了孟加拉国SARS-CoV-2 Omicron的演变
Mohammad Tanbir Habib1, Saikt Rahman1, Mokibul Hassan Afrad2
1Institute for Developing Science and Health Initiatives, Dhaka, Bangladesh.
Frontiers in genetics
|August 25, 2023
概括
孟加拉国的SARS-CoV-2 Omicron变种显示出适应性进化,特别是在其尖端蛋白中.
科学领域:
- 病毒学和进化生物学
- 基因组学和生物信息学
背景情况:
- 严重急性呼吸系统综合征冠状病毒2 (SARS-CoV-2) Omicron,一种高度传染的变种,表现出免疫逃逸.
- 了解Omicron的演变以及疫情的驱动因素至关重要.
- 尖端蛋白受体结合域 (RBD) 替代是Omicron免疫逃避和ACE2相互作用的关键.
研究的目的:
- 来自孟加拉国的SARS-CoV-2 Omicron基因组的适应性进化研究.
- 在积极选择下识别特定的基因和部位.
- 了解选择压力在这个地区Omicron的演变中的作用.
主要方法:
- 来自孟加拉国的SARS-CoV-2 Omicron基因组的分析 (GISAID数据库).
- 计算非同义词与同义词替代率比率 (Ka/Ks或 ω) 以检测选择压力.
- 识别具有 ω > 1 (正选择) 或 ω ≈ 0 (净化选择) 的编码子.
主要成果:
- 来自孟加拉国的SARS-CoV-2 Omicron的尖 (S) 基因中的适应性进化的证据.
- 在S基因中的22个编码位显示了积极选择的特征.
- 尖端葡萄糖蛋白的RBD是适应性进化的热点,其中的密码体显示 ω > 1.
- M基因和ORF6也显示出积极选择的迹象.
- 一些已识别的适应性RBD网站与增加的病毒适应性有关.
结论:
- 净化选择是主要的进化力量,但积极的达尔文选择显著影响了孟加拉国的SARS-CoV-2 Omicron进化.
- 关键病毒基因的适应性进化,包括尖端蛋白的RBD,有助于Omicron的特征.
- 持续监测病毒演变对于理解和管理SARS-CoV-2疫情至关重要.
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