保存的HIV-1间隔2触发了矩阵格子成熟的过程
James C V Stacey1,2, Dominik Hrebík1, Elizabeth Nand3
1Department of Cell and Virus Structure, Max Planck Institute of Biochemistry, 82152 Martinsried, Germany.
bioRxiv : the preprint server for biology
|November 22, 2024
概括
间隔2 (SP2) 结合人类免疫缺陷病毒1型 (HIV-1) 的MA蛋白,触发其结构成熟. 这种相互作用对于形成传染性HIV-1病毒和增强病毒融合至关重要.
科学领域:
- 病毒学 病毒学
- 结构生物学 结构生物学
- 分子生物学分子生物学
背景情况:
- 人类免疫缺陷病毒1型 (HIV-1) 病毒从未成熟的非传染性状态成熟到传染性形式,通过Gag多蛋白的蛋白质分解裂变.
- 艾滋病毒-1的矩阵蛋白 (MA) 在不成熟的病毒细胞中形成一个六边形格子,在分裂时转换为成熟的格子结构.
- 驱动MA网格结构成熟的机制仍然是难以捉摸的.
研究的目的:
- 阐明艾滋病毒-1中MA格子成熟的机制.
- 为了确定MA网格结构转变的触发因素.
- 为了确定保存的间隔2 (SP2) 的功能.
主要方法:
- 高分辨率的病毒内结构确定MA.
- 分析了Gag分离部位的突变物.
- 纯化MA在脂质层上的体外成熟试验.
- 病毒融合试验.
主要成果:
- 间隔2 (SP2) 与MA结合,诱导MA网格的结构成熟.
- 马结合SP2在蛋白质-蛋白质接口中稳定成熟的网格,而不是在脂质结合口袋中.
- 从Gag中释放SP2对于MA成熟至关重要.
- 单独SP2可以在体外诱导MA在脂质层上的成熟.
- SP2诱导的MA成熟加速了HIV-1与目标细胞的融合.
结论:
- SP2是HIV-1中MA结构成熟的触发因素.
- SP2在稳定成熟的MA网格的蛋白质-蛋白质相互作用中起到关键作用.
- SP2和MA之间的相互作用是一个新的发现,它解释了MA格子的成熟,并为SP2赋予了功能.
- 通过促进更快的细胞融合,SP2介导的成熟增强了病毒感染力.
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