State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin 150036, China.
National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences (CAS), Beijing 100101, China.
Viruses. 2022 Feb 5;14(2):327. doi: 10.3390/v14020327.
Getah virus (GETV) is a member of the alphavirus genus, and it infects a variety of animal species, including horses, pigs, cattle, and foxes. Human infection with this virus has also been reported. The structure of GETV has not yet been determined. In this study, we report the cryo-EM structure of GETV at a resolution of 3.5 Å. This structure reveals conformational polymorphism of the envelope glycoproteins E1 and E2 at icosahedral 3-fold and quasi-3-fold axes, which is believed to be a necessary organization in forming a curvature surface of virions. In our density map, three extra densities are identified, one of which is believed a "pocket factor"; the other two are located by domain D of E2, and they may maintain the stability of E1/E2 heterodimers. We also identify three N-glycosylations at E1 N141, E2 N200, and E2 N262, which might be associated with receptor binding and membrane fusion. The resolving of the structure of GETV provides new insights into the structure and assembly of alphaviruses and lays a basis for studying the differences of biology and pathogenicity between arthritogenic and encephalitic alphaviruses.
基孔肯雅病毒（GETV）属于甲病毒属，可感染多种动物物种，包括马、猪、牛和狐狸。也有人类感染该病毒的报道。目前尚未确定 GETV 的结构。在本研究中，我们报告了 GETV 的冷冻电镜结构，分辨率为 3.5Å。该结构揭示了衣壳蛋白 E1 和 E2 在二十面体 3 倍和准 3 倍轴上的构象多态性，这被认为是形成病毒曲率表面的必要组织。在我们的密度图中，鉴定出三个额外的密度，其中一个被认为是“口袋因子”；另外两个位于 E2 的结构域 D 处，它们可能维持 E1/E2 异二聚体的稳定性。我们还鉴定了 E1 N141、E2 N200 和 E2 N262 上的三个 N-糖基化位点，这些位点可能与受体结合和膜融合有关。GETV 结构的解析为甲病毒的结构和组装提供了新的见解，并为研究关节炎和脑炎型甲病毒之间的生物学和致病性差异奠定了基础。
