裂谷热病毒包裹蛋白的冷EM结构与强大的中和抗体复合在一起
Linjing Zhang1,2,3, Kaiwen Meng1,2,3, Ye Xiang1,2,3
1Beijing Frontier Research Center for Biological Structure, Center for Infection Biology, School of Basic Medical Sciences, Tsinghua University, Beijing 100084, People's Republic of China.
概括
裂谷热病毒 (RVFV) 糖蛋白 Gn 和 Gc 的结构细节使用冷EM揭示出来. 发现一种中和抗体 (RVFV-140) 通过稳定 GnGc 六合体的预注射构造来阻止病毒的进入.
科学领域:
- 结构生物学是结构生物学.
- 病毒学 病毒学
- 免疫学 免疫学 免疫学
背景情况:
- 裂谷热病毒 (RVFV) 进入宿主细胞是由其Gn和Gc糖蛋白促进的.
- 对于RVFV Gn和Gc的精确结构组织和组装机制的理解尚不完全.
研究的目的:
- 为了阐明RVFV GnGc六合体的近原子分辨率结构.
- 了解中和抗体RVFV-140抑制病毒进入的机制.
主要方法:
- 使用冷电子显微镜 (cryo-EM) 来确定GnGc六合体的结构.
- 使用中和单克隆抗体RVFV-140及其碎片抗原结合 (Fab) 域 (Fab140) 来稳定糖蛋白复合体.
- 对蛋白质-蛋白质相互作用和参与六体组装的构造变化的分析.
主要成果:
- 与Fab140复合的GnGc六合体的结构以近原子分辨率确定.
- RVFV-140与三元性表位结合,交叉连接相邻的Gn头,并防止输血前到输血后的过渡.
- 六合体内的内部和间糖蛋白相互作用涉及范德瓦尔斯力和键,主要是Gn头和特定的Gn/Gc域之间.
- 六合体组装需要在Gn和Gc链区域的特定循环中发生显著的形状变化.
- 再组合的GnGc体主要通过Gc域I残留物 (693-713) 相互作用,根据当地环境的变化.
结论:
- 该结构为RVFV进入的机制以及Gn和Gc糖蛋白的功能提供了关键的见解.
- 中和抗体RVFV-140通过将糖蛋白锁定在预注液状态中起作用,从而抑制病毒的进入.
- 了解这些相互作用对于开发针对RVFV的向抗病毒疗法至关重要.
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