Structures of the portal vertex in dsDNA viruses and virus-infected cells

双链 DNA 病毒和病毒感染细胞的门静脉顶点结构

基本信息

批准号：
7847601
负责人：
Wah Chiu
金额：
$ 50.58万
依托单位：
BAYLOR COLLEGE OF MEDICINE
依托单位国家：
美国
项目类别：
财政年份：
2009
资助国家：
美国
起止时间：
2009-05-22 至 2012-04-30
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/7847601
关键词：
3-Dimensional Adhesions Bacterial Adhesins Bacteriophage P22 Bacteriophages Binding Biological Models Biology Caliber Capsid Capsid Proteins Cell Communication Cell Nucleus Cell surface Cell-Matrix Junction Cells Classification Collaborations Complex Cryoelectron Microscopy DNA DNA Packaging DNA Sequence Rearrangement DNA delivery Development Disease Docking Double Stranded DNA Virus Electron Microscopy Genome Herpesviridae Herpesvirus 1 Human Image In Situ Individual Infection Injection of therapeutic agent Investigation Membrane Methodology Methods Molecular Structure Morphogenesis Nuclear Envelope Nuclear Pore Nuclear Receptors Nucleic Acids Pathway interactions Pharmaceutical Preparations Population Principal Investigator Procedures Process Proteins Protocols documentation Research Personnel Resolution Salmonella Scaffolding Protein Staging Structure Tail Technology Tomogram Viral Virion Virus Work abstracting anti-viral gene delivery base cell envelope cellular imaging computerized tools ds-DNA image reconstruction mutant particle pathogen programs protein complex reconstruction terminase tomography viral DNA virology

项目摘要

Program Director/Principal Investigator (Last, First, Middle): Chiu, Wah 1R01 AI075208-01A1 ABSTRACT Herpesviruses are major pathogens in human populations, causing disease in normal and immuno-compromised individuals. Double-stranded DNA (dsDNA) tailed bacterial viruses and herpesviruses share surprising similarities in capsid assembly and organization. In both viral classes, a precursor (procapsid) shell is formed with the help of scaffolding proteins. During viral/phage morphogenesis, newly replicated dsDNA is inserted into the procapsid by a terminase protein complex through a unique portal vertex, which contains multiple gene products. In addition, both viruses deliver their nucleic acid into a membrane bound compartment while the emptied capsids remain outside this compartment. These similarities in assembly, structure, and infection suggest that herpesviruses and dsDNA phages arose from a common ancestor. The portal and associated proteins are critical in the transport of the DNA genome from the virion across the bacterial envelope for phage, and across the nuclear envelope for Herpesvirus. Until very recently the structures of such complexes - lacking icosahedral symmetry - could not be resolved by current structure analysis methods. Recent advances in asymmetric single particle reconstructions from electron cryo-microscopy images of the infectious virions of epsilon15 and P22 phages have revealed details of components of the portal vertex. However, the structural organization of the portal vertex before DNA entry and later when the DNA exits, remains to be determined. Our recent results with the herpesvirus capsid and virion suggest that its portal organization is also similar to that of the phage portal. The herpesvirus portal vertex may act like the phage portal vertex, and rearrange to release or deliver DNA into the cell nucleus. Such an apparatus presents a potential target for anti-viral therapies. We propose to use electron cryo-microscopy and electron cryo-tomography to visualize higher resolution features in the portal vertex in the herpesvirus virion and to determine the structural rearrangements of the phage portal vertex during the process of DNA ejection into host cells. The structures to be determined include not only the isolated virus particles but also the forms generated upon interaction with the host cell and release of DNA. The imaging and computational tools developed for these investigations should be generally applicable to the infection processes of many other viruses. The proposed studies, when combined with other biological and modeling information, will yield valuable structural information for developing anti-viral and gene delivery strategies targeted at these processes.

项目总监/首席调查员（最后一个，中间）：Chiu，WAH 1R01 AI075208-01A1 抽象的疱疹病毒是人群中的主要病原体，导致正常和免疫功能低下的个体疾病。双链DNA（DsDNA）尾部细菌病毒和疱疹病毒在衣壳组装和组织中具有令人惊讶的相似性。在两个病毒类别中，都在脚手架蛋白的帮助下形成前体（procapsid）壳。在病毒/噬菌体的形态发生过程中，新复制的dsDNA通过含有多个基因产物的独特门户顶点插入了末端酶蛋白复合物中的propapsid。此外，这两种病毒都将其核酸输送到膜结合的隔室中，而空的衣壳仍留在此隔室之外。组装，结构和感染中的这些相似之处表明，疱疹病毒和dsDNA噬菌体源于共同的祖先。门户和相关蛋白对于从病毒粒子从细菌包膜中以及跨越疱疹病毒的核包膜中的DNA基因组运输至关重要。直到最近，这种复合物的结构（缺乏二十面体对称性）才能通过当前的结构分析方法来解决。来自epsilon15和p22噬菌体的传染性病毒体的电子冷冻微镜图像的不对称单粒子重建的最新进展揭示了门户顶点的组件的细节。但是，在DNA进入之前和DNA退出时，门户网站顶点的结构组织仍有待确定。我们最近在疱疹病毒Capsid和Virion的结果表明，其门户组织也类似于噬菌体门户网站。疱疹病毒门户网站顶点可能像噬菌体门户顶点一样，重新排列以释放或将DNA释放到细胞核中。这样的设备为抗病毒疗法提供了潜在的靶标。我们建议使用电子冷冻微镜和电子冷冻术摄影，以可视化疱疹病毒病毒病毒病毒的门口顶点中的更高分辨率特征，并确定在DNA射出宿主细胞过程中噬菌体门户顶点的结构重排。要确定的结构不仅包括与宿主细胞相互作用和DNA释放时产生的形式产生的形式。为这些研究开发的成像和计算工具通常应适用于许多其他病毒的感染过程。拟议的研究与其他生物学和建模信息结合使用，将产生有价值的结构信息，以制定针对这些过程的抗病毒和基因输送策略。