轮状病毒VP5*/VP8*的形状转变使膜透到Ca2中
Marilina de Sautu1,2, Tobias Herrmann1, Gustavo Scanavachi3,4
1Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, Massachusetts, United States of America.
PLoS pathogens
|April 4, 2024
概括
罗塔病毒通过形成膜囊泡并释放它们的遗传物质进入细胞. 这项研究证实,外部病毒蛋白VP4插入囊泡膜,形成病毒进入所必需的泄漏.
科学领域:
- 病毒学 病毒学
- 细胞生物学 细胞生物学
- 结构生物学 结构生物学
背景情况:
- 罗塔病毒是双链RNA病毒,通过将内核粒子 (双层粒子,DLP) 输送到细胞质中来感染细胞.
- 病毒进入涉及外层囊层,它介导吸收到囊泡和随后的DLP释放.
研究的目的:
- 为了验证轮状病毒进入的拟议机制,特别是外层蛋白质VP4在膜相互作用和流中的作用.
- 提供早期轮状病毒进入事件的分子描述.
主要方法:
- 活细胞成像用于追踪轮状病毒 (状轮状病毒,RRV) 进入阶段.
- 低温电子显微镜 (cryo-EM) 和断层扫描 (cryo-ET) 用于结构分析.
- 脂质体附着病毒的冷EM (三层颗粒,TLPs).
- 脂质体附着TLP的单颗粒光成像.
主要成果:
- 确认轮状病毒的进入涉及膜包裹和吞,导致囊泡中的Ca2+损失.
- 通过冷-EM和光成像,证明了VP4 C-终端段插入脂质体膜.
- 表明这种插入会产生Ca2+泄漏,支持拟议的进入机制.
结论:
- VP4 C端段插入目标细胞膜是轮状病毒进入的关键事件.
- 这种机制促进了Ca2+的流入,这对于释放双层粒子至关重要.
- 这些发现为早期的轮状病毒细胞相互作用提供了详细的分子理解.
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