对于卡波西肉瘤相关的疹病毒编码的GPCR的连接物杂交和高信号活性的结构基础
Jun Bae Park1, Bibekananda Sahoo2, Amita Rani Sahoo2
1Cancer Biology Department, Infection Biology Program, and Global Center for Pathogen and Human Health Research, Lerner Research Institute, Cleveland Clinic, Cleveland, OH, USA.
Nature communications
|September 25, 2025
概括
卡波西肉瘤相关的疹病毒ORF74,一种病毒受体,由于其开放的结构,显示出高的基底信号传递,使带乱交和自发激活对于病毒瘤发生至关重要.
科学领域:
- 结构生物学 结构生物学
- 病毒学 病毒学
- 分子生物学分子生物学
背景情况:
- 卡波西的肉瘤相关疹病毒 (KSHV) 编码ORF74,一种病毒G蛋白结合受体 (GPCR).
- ORF74与人类的CXCR2同源,并通过高基底信号传递在卡波西肉瘤的发展中发挥关键作用.
- 了解ORF74的结构和信号传递对于向KSHV驱动的瘤发生至关重要.
研究的目的:
- 阐明ORF74的结合体独立和构成信号的结构基础.
- 调查ORF74的连接体乱交和自发激活的基础机制.
- 确定调节ORF74活动的关键区域,以实现潜在的治疗向.
主要方法:
- 低温电子显微镜 (cryo-EM) 用于确定不同状态的ORF74结构.
- 分子动力学模拟 (元动力学) 探索结构动力学.
- 构建和分析CXCR2-ORF74模拟器以探测功能区域.
主要成果:
- 冷EM揭示了ORF74的静态,开放的细胞外腔,促进了连接体的乱交.
- 结构分析发现了微开关 (CWxP,E/DRY,NPxxY) 稳定了活性构造,导致构成信号.
- 超动力学模拟支持通过非活跃状态和活跃状态之间的动态组合的自发激活.
- CXCR2-ORF74仿真体确定了细胞内循环2和3对于基底和激素诱导活性至关重要.
结论:
- 这项研究定义了ORF74的配体乱交和高基底信号的结构基础.
- 阐明了ORF74的自发激活机制,突出了它在病毒瘤发生中的作用.
- 对ORF74结构-功能关系的洞察力为开发向的KSHV疗法提供了基础.
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