拉萨病毒跨膜域内的pH依赖的构造变化引起了高效的膜融合
Patrick M Keating1, Nicholas P Schifano1, Xinrui Wei1
1Department of Chemistry and Biochemistry, University of Maryland, College Park, MD 20742, USA.
Biochimica et biophysica acta. Biomembranes
|September 21, 2023
概括
拉萨病毒糖蛋白2 (GP2) 经历了pH依赖的结构变化,这对膜融合至关重要. 了解跨膜领域的这些变化可能会导致新的拉萨热病治疗方法.
科学领域:
- 病毒学 病毒学
- 结构生物学 结构生物学
- 生物化学 生物化学
背景情况:
- 拉萨病毒 (LASV) 引起拉萨热,这是一个严重的公共卫生威胁,目前没有疫苗或治疗方法.
- 由糖蛋白2 (GP2) 介导的病毒膜融合对LASV感染至关重要.
- 聚变期间GP2跨膜域的结构细节在很大程度上是未知的.
研究的目的:
- 调查在膜融合过程中拉萨病毒GP2跨膜域的结构和功能作用.
- 为了阐明GP2内的pH依赖性构造变化.
主要方法:
- 循环二重化 (CD) 和核磁共振 (NMR) 光谱被用来研究构造变化.
- 用于评估特定区域的功能影响的定位基因突变 (proline突变物).
- 开发了一种修改后的脂质混合试验,以量化膜融合效率.
主要成果:
- CD和NMR揭示了在GP2跨膜域的N端的pH依赖的α螺旋延伸.
- 这一区域的氨酸突变取消了螺旋延伸,并降低了膜融合效率.
- 在低pH下,融合效率是最佳的,在突变物中观察到活性降低.
结论:
- 在GP2跨膜域中的pH依赖的构造变化对于拉萨病毒膜融合至关重要.
- 这些发现为LASV融合机制和潜在的治疗点提供了洞察力.
- 针对这些形状变化可以提供一种策略,用于开发针对拉萨热的抗病毒疗法.
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