对KSHV-GPCR构成性激活和CXCL1化学基因识别的结构洞察
Aijun Liu1,2, Yezhou Liu1, Clàudia Llinàs Del Torrent Masachs3
1Kobilka Institute of Innovative Drug Discovery, School of Medicine, The Chinese University of Hong Kong, Shenzhen, Guangdong 518172, China.
概括
卡波西卡波西 (Kaposi Kaposi) 是一个
科学领域:
- 病毒学 病毒学
- 结构生物学 结构生物学
- 免疫学 免疫学 免疫学
背景情况:
- 卡波西肉瘤相关性疹病毒 (KSHV) 编码KSHV-GPCR,这是一个病毒G蛋白合受体,对免疫逃避和卡波西肉瘤的发病至关重要.
- KSHV-GPCR与CXCR2具有很高的相似性,并且具有构成性活性,在疹病毒GPCR中很常见.
研究的目的:
- 阐明KSHV-GPCR依赖体和构成性激活的结构基础.
- 了解KSHV-GPCR与G蛋白和化学因子连接体相互作用的分子机制.
主要方法:
- 使用高分辨率冷电子显微镜 (cryo-EM) 来确定KSHV-GPCR-Gi复合物的结构.
- 对于apo-KSHV-GPCR-Gi和与CXCL1化学基因结合的复合物,都获得了结构.
- 为了验证结构发现,进行了功能性测试.
主要成果:
- Apo-KSHV-GPCR-Gi结构揭示了细胞外循环2在受体构成性激活中的作用.
- 结合CXCL1的结构阐明了一种新的双位体连接体结合模式和详细的CXCL1相互作用.
- 结构模型通过功能测定得到证实,支持双重激活机制.
结论:
- KSHV-GPCR采用了一种涉及细胞外循环2的双激活机制,以及CXCL1.1的双位点结合模式.
- 这种机制是免疫逃避的进化适应,有助于卡波西肉瘤的发病.
- 这些结构性见解为开发针对KSHV感染的治疗策略提供了潜力.
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