Near-atomic cryo-electron microscopy structures of varicella-zoster virus capsids

VZV是一种广泛存在并且具有高度传染性的人类α-疱疹病毒。初次感染VZV可导致水痘，人群普遍易感（感染率约为61%～100%）。该病毒可在背根神经节潜伏感染，持续终生。夏宁邵教授团队长期开展VZV相关基础与新型疫苗研究，通过系统和精细探索建立了高效的VZV规模化培养和病毒颗粒纯化技术体系，成功获得高质量的VZV颗粒样品。首次揭示了疱疹病毒α家族的水痘-带状疱疹病毒（VZV）不同类型核衣壳的近原子分辨率结构，阐明了VZV核衣壳不同组成蛋白的相互作用网络与衣壳装配机制，可为进一步开展新型载体疫苗设计及抗病毒药物等研究提供重要支持。 我校博士后王玮、高级工程师郑清炳、博士生潘德全和俞海副教授为该论文共同第一作者，我校夏宁邵教授、程通副教授、李少伟教授以及美国罗格斯大学朱桦（Hua Zhu）教授、加利福尼亚大学洛杉矶分校周正洪（Z. Hong Zhou）教授为该论文的共同通讯作者。【Abstract】Varicella-zoster virus (VZV) is a medically important human herpesvirus that causes chickenpox and shingles, but its cell-associated nature has hindered structure studies. Here we report the cryo-electron microscopy structures of purified VZV A-capsid and C-capsid, as well as of the DNA-containing capsid inside the virion. Atomic models derived from these structures show that, despite enclosing a genome that is substantially smaller than those of other human herpesviruses, VZV has a similarly sized capsid, consisting of 955 major capsid protein (MCP), 900 small capsid protein (SCP), 640 triplex dimer (Tri2) and 320 triplex monomer (Tri1) subunits. The VZV capsid has high thermal stability, although with relatively fewer intra- and inter-capsid protein interactions and less stably associated tegument proteins compared with other human herpesviruses. Analysis with antibodies targeting the N and C termini of the VZV SCP indicates that the hexon-capping SCP—the largest among human herpesviruses—uses its N-terminal half to bridge hexon MCP subunits and possesses a C-terminal flexible half emanating from the inner rim of the upper hexon channel into the tegument layer. Correlation of these structural features and functional observations provide insights into VZV assembly and pathogenesis and should help efforts to engineer gene delivery and anticancer vectors based on the currently available VZV vaccine.This research was supported by grants from the National Science and Technology Major Projects for Major New Drugs Innovation and Development (no. 2018ZX09711003-005-003), the National Science and Technology Major Project of Infectious Diseases (no. 2017ZX10304402), the National Natural Science Foundation of China (no. 81871648, 81601762), the Research Unit of Frontier Technology of Structural Vaccinology of Chinese Academy of Medical Sciences (no. 2019RU022) and the US National Institutes of Health (DE025567/028583). 该研究获得了国家自然科学基金、新药创制国家科技重大专项和传染病防治国家科技重大专项等资助

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Chiral Primary Amine/Ketone Cooperative Catalysis for Asymmetric α-Hydroxylation with Hydrogen Peroxide

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Near-atomic cryo-electron microscopy structures of varicella-zoster virus capsids

Varicella-zoster virus (VZV) is a medically important human herpesvirus that causes chickenpox and shingles, but its cell-associated nature has hindered structure studies. Here we report the cryo-electron microscopy structures of purified VZV A-capsid and C-capsid, as well as of the DNA-containing capsid inside the virion. Atomic models derived from these structures show that, despite enclosing a genome that is substantially smaller than those of other human herpesviruses, VZV has a similarly sized capsid, consisting of 955 major capsid protein (MCP), 900 small capsid protein (SCP), 640 triplex dimer (Tri2) and 320 triplex monomer (Tri1) subunits. The VZV capsid has high thermal stability, although with relatively fewer intra- and inter-capsid protein interactions and less stably associated tegument proteins compared with other human herpesviruses. Analysis with antibodies targeting the N and C termini of the VZV SCP indicates that the hexon-capping SCP-the largest among human herpesviruses-uses its N-terminal half to bridge hexon MCP subunits and possesses a C-terminal flexible half emanating from the inner rim of the upper hexon channel into the tegument layer. Correlation of these structural features and functional observations provide insights into VZV assembly and pathogenesis and should help efforts to engineer gene delivery and anticancer vectors based on the currently available VZV vaccine