塞姆利基森林病毒的冷冻电镜结构研究
贾旭东#，李锶铎#，于宏洋#，张勤奋，何 键*
（1.中山大学，生命科学学院，广东 广州 510275；2.生物岛实验室，广东 广州 510005）
摘 要 塞姆利基森林病毒（Semliki forest virus, SFV）是一种典型的甲病毒，主要通过节肢动物作为媒介进行传播，对人类及多种哺乳动物构成潜在的感染威胁。然而当前针对SFV的结构生物学研究相对不足，限制了对其在病毒-宿主互作、入侵机制以及病毒颗粒组装与成熟过程的认知。本研究采用冷冻电镜技术对SFV成熟颗粒的三维结构进行了高精度解析，并系统分析了囊膜蛋白E1和E2上的N-糖基化位点及二硫键，揭示了这些结构特征在维持病毒蛋白稳定性中的关键作用。这些发现对于阐明SFV的生物学特性、推动抗病毒药物研发及优化疫苗设计都具有重要意义。
关键词 塞姆利基森林病毒；甲病毒；N-糖基化；二硫键；冷冻电镜
中图分类号：Q336；Q937
文献标识码：Doi:10.3969/j.issn.1000-6281.2025.01.003
Structural study of Semliki forest virus through Cryo-EM
JIA Xudong#, LI Siduo#, YU Hongyang#, ZHANG Qinfen, HE Jian*
(1.School of Life Sciences, Sun Yat-sen University, Guangzhou Guangdong 510275；2.Bioland Lab, Guangzhou Guangdong 510005，China)
Abstract Semliki forest virus (SFV), a typical member of the Alphavirus genus, is mainly transmitted through arthropod vectors and poses a potential infection threat to humans and various mammals. However, the current structural biology research on SFV is relatively insufficient, which limits the understanding of its interactions with host cells, invasion mechanisms, and the processes involved in virion assembly and maturation. To address this, we analyzed the three-dimensional structure of mature SFV particles using cryo-electron microscopy technology. The N-glycosylation sites and disulfide bonds on envelope proteins E1 and E2 were systematically analyzed, revealing their key roles in maintaining viral protein stability. These findings are of significance for elucidating the biological characteristics of SFV, advancing antiviral drug development, and optimizing vaccine design.
Keywords Semliki forest virus；alphavirus；N-glycosylation；disulfide bond；Cryo-EM
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