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：
7526288
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 2011-04-30
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/7526288
关键词：
Bacteria Bacterial Adhesins Bacteriophage P22 Bacteriophages Binding Biochemical Biological Models Biology Caliber Capsid Capsid Proteins Cell Communication Cell Nucleus Cell surface Cell-Matrix Junction Cells Collaborations Complex Cryoelectron Microscopy DNA DNA Packaging DNA Sequence Rearrangement DNA delivery Development Disease Docking Double Stranded DNA Virus Electron Microscopy Funding Genome Herpesviridae Herpesvirus 1 Human Image In Situ Individual Infection Injection of therapeutic agent Investigation Medicine Membrane Methodology Methods Molecular Conformation Molecular Structure Morphogenesis Nuclear Envelope Nucleic Acids Pathway interactions Pharmaceutical Preparations Population Principal Investigator Procedures Process Proteins Protocols documentation Research Personnel Resolution Salmonella Salmonella Phages Scaffolding Protein Staging Structure Tail Universities Viral Viral Proteins Virion Virus Work abstracting anti-viral gene delivery base cell envelope college computerized tools ds-DNA electron tomography 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.

项目主任/首席研究员（姓、名、中）：赵华 1R01 AI075208-01A1 抽象的疱疹病毒是人群中的主要病原体，在正常和免疫功能低下的个体中引起疾病。双链 DNA (dsDNA) 尾细菌病毒和疱疹病毒在衣壳组装和组织方面具有惊人的相似之处。在这两个病毒类别中，前体（原衣壳）外壳是在支架蛋白的帮助下形成的。在病毒/噬菌体形态发生过程中，新复制的 dsDNA 通过终止酶蛋白复合物通过独特的门户顶点插入衣壳，其中包含多种基因产物。此外，两种病毒都将其核酸递送到膜结合区室中，而空的衣壳保留在该区室之外。这些在组装、结构和感染方面的相似性表明疱疹病毒和 dsDNA 噬菌体起源于共同的祖先。对于噬菌体来说，门户网站和相关蛋白对于病毒颗粒的 DNA 基因组穿过细菌包膜以及疱疹病毒穿过核包膜的运输至关重要。直到最近，这种缺乏二十面体对称性的配合物的结构还无法通过当前的结构分析方法来解析。根据 epsilon15 和 P22 噬菌体感染性病毒粒子的电子冷冻显微镜图像进行不对称单粒子重建的最新进展揭示了门静脉顶点组成的细节。然而，DNA 进入之前和之后 DNA 退出时门顶点的结构组织仍有待确定。我们最近对疱疹病毒衣壳和病毒体的研究结果表明，其门户组织也与噬菌体门户相似。疱疹病毒门顶点可以像噬菌体门顶点一样发挥作用，并重新排列以释放或递送DNA到细胞核中。这种装置为抗病毒治疗提供了潜在的靶标。我们建议使用电子冷冻显微镜和电子冷冻断层扫描来可视化疱疹病毒病毒体门顶点的更高分辨率特征，并确定噬菌体门顶点在DNA喷射到宿主细胞的过程中的结构重排。待确定的结构不仅包括分离的病毒颗粒，还包括与宿主细胞相互作用和释放DNA时产生的形式。为这些研究开发的成像和计算工具应该普遍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相结合，将为开发针对这些过程的抗病毒和基因传递策略提供有价值的结构信息。