对HIV-1 Vif多态性选择压力的全球和时间动态的计算探索
Md Sakil Arman1, Md Zafrul Hasan1
1Department of Biochemistry and Molecular Biology, Shahjalal University of Science and Technology, Sylhet 3114, Bangladesh.
Virus research
|January 18, 2024
概括
艾滋病毒-1 Vif 蛋白通过保护关键功能区域,特别是与 APOBEC3 相互作用的区域,适应宿主防御. 这种由免疫压力驱动的适应性表明,特定的Vif区域是HIV-1感染的潜在治疗点.
科学领域:
- 病毒学 病毒学
- 免疫学 免疫学 免疫学
- 计算生物学 计算生物学
背景情况:
- 人类免疫缺陷病毒1型 (HIV-1) 病毒感染因子 (Vif) 蛋白质对于病毒复制至关重要.
- Vif对抗宿主APOBEC3蛋白质,这些蛋白质通常会限制病毒感染力.
- 艾滋病毒-1的进化受到人类白细胞抗原 (HLA) 和病毒遗传多样性等宿主因素的影响,使疫苗开发复杂化.
研究的目的:
- 通过计算分析HIV-1 Vif基因的进化动态和功能约束.
- 确定受选择压力下的VIF区域,并评估它们对蛋白质稳定性和宿主相互作用的影响.
- 探索Vif蛋白内潜在的治疗点.
主要方法:
- 从洛斯阿拉莫斯国家实验室数据库 (1998-2021) 中分析了超过5万个HIV-1 M vif序列.
- 选择压力 (dn/ds比) 和蛋白质随时间推移的的计算.
- 使用计算工具预测突变频率,序列保存以及误解突变对Vif蛋白稳定性和Vif-APOBEC3结合接口的影响.
主要成果:
- 观察到vif基因 (dn/ds=1.58) 的积极选择压力,随着时间的推移,dn/ds的下降趋势和蛋白质的增加趋势.
- 在研究期间,对Vif共识序列的预测突变频率显著下降.
- 在关键的功能动机 (F1,F2,F3,G,BC盒,CBFβ结合区域) 中发现了序列保存,而N-/C-终端和指区域的变异性很突出,可能是由于HLA-I受限制的CD8+ T细胞压力.
- 预计Missense突变,特别是Vif-APOBEC3结合接口 (例如R17K,Y44F) 的突变会破坏Vif-APOBEC3相互作用的稳定性.
结论:
- 艾滋病毒-1 Vif通过保留APOBEC3对抗性至关重要的功能动机来适应宿主生理学.
- 免疫压力,特别是来自CD8+T细胞的免疫压力,驱动特定Vif区域的变异性.
- 保存的Vif-APOBEC3相互作用点代表了新型抗HIV-1疗法的有希望的目标.
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