Structural studies of Togaviruses

披膜病毒的结构研究

• 批准号: 8286599
• 负责人: MICHAEL G ROSSMANN
• 金额: $ 64.23万
• 依托单位: PURDUE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2012
• 资助国家: 美国
• 起止时间: 2012-02-20 至 2017-01-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8286599
• 关键词: Africa; Alphavirus; Antibodies; Applications Grants; Asia; Capsid Proteins; Cell fusion; Cells; Chikungunya virus; Collaborations; Complex; Cryoelectron Microscopy; Crystallography; Cytoplasm; Dependence; Electron Microscopy; Electrons; Endocytosis; Fab Immunoglobulins; Family; Gene Order; Genome; Glycoproteins; Grant; Health; Homologous Gene; Human; Image; Immunoglobulin Fragments; India; Individual; Infection; Investigation; Life Cycle Stages; Lipids; Maps; Membrane Lipids; Microscopic; Monoclonal Antibodies; Morphology; NIH Vaccine Research Center; Nucleocapsid; Peptide antibodies; Peptides; Play; Process; Recombinants; Reliance; Resolution; Role; Rubella virus; Sindbis Virus; Southeastern Asia; Staging; Structure; Surface; Techniques; Technology; Togaviridae; Tomogram; Vaccines; Viral; Viral Proteins; Virion; Virus; Virus Inhibitors; Virus-like particle; Work; World Health; X-Ray Crystallography; base; design; electron density; electron tomography; improved; inhibitor/antagonist; insight; mutant; neutralizing antibody; neutralizing monoclonal antibodies; particle; pathogen; polypeptide; receptor; reconstruction; structural biology; tool; virology

DESCRIPTION (provided by applicant: Crystallography was the primary structural tool that first opened up structural investigation of viruses at near-atomic resolution. However, larger viruses with lipid envelopes are too variable in their structures and have too small a proportion of their surface involved in lattice contacts to make stable crystals. Cryo-electron microscopy later emerged as the leading tool for advancing Structural Biology to give the "big picture", with crystallography playing a supporting role in the determination of the crystallizable viral components. Single particle averaging of cryo-electron microscopic images is now approaching almost atomic resolution in favorable cases but, once again, the limits of this technology are becoming apparent in the investigations of progressively more complex pleomorphic assemblies. Cryo-electron tomography has now emerged as an invaluable tool for the determination of the structure of individual viral particles without reliance on averaging between symmetrically equivalent components or on the availability of identical homogeneous particles. However, the resolution of a tomographic reconstruction is insufficient to determine structure in atomic detail. Thus, a part of this grant application is dedicated towards extracting more information from tomograms, especially as applied to the slightly pleomorphic, structurally largely unknown, Rubella virus. Alphaviruses and Rubella virus constitute the Togavirus family because of their similarity in gene order and morphology. Among alphaviruses, Chikungunya virus is a major world health concern because of its recent re-emergence in Asia and Africa. We plan to extend our previous studies of the icosahedral, lipid containing alphaviruses, and tackle the more difficult structural analysis of pleomorphic Rubella virus. Specifically, we are planning to extend the resolution of Chikungunya virus-like particles to near-atomic resolution using cryo-electron microscopy in part as an aid to the design of a vaccine against Chikungunya virus with Gary Nabel at the NIH Vaccine Research Center. We also plan to determine the structure of Rubella virus by analyses of electron tomograms. We plan to use antibodies and peptide inhibitors to block maturation, attachment and fusion with host cells in order to study the structural intermediates encountered in the viral life cycle. We are planning to determine the remaining unknown structures of the Rubella virus components and use both crystallography and electron microscopy to study their interactions with each other and with antibodies. PUBLIC HEALTH RELEVANCE: Alphaviruses can be lethal human pathogens and the recent emergence of Chikungunya virus (an alphavirus) in India and Southeast Asia is a major concern to world health. Thus, our studies with neutralizing antibodies and peptides that inhibit infection are relevant to major current health concerns. Furthermore, our studies depend on extending current structural techniques to pleomorphic viruses, thus making possible structural studies of numerous, lipid membrane containing enveloped viruses (such as Rubella virus, an alphavirus homologue) that were previously out of range.

DESCRIPTION (provided by applicant: Crystallography was the primary structural tool that first opened up structural investigation of viruses at near-atomic resolution. However, larger viruses with lipid envelopes are too variable in their structures and have too small a proportion of their surface involved in lattice contacts to make stable crystals. Cryo-electron microscopy later emerged as the leading tool for advancing Structural Biology to give the "big picture", with crystallography playing在确定可结晶的病毒成分中的支撑作用。不依赖对称等效的组件之间的平均值或相同均匀粒子的可用性。但是，断层重建的分辨率不足以确定原子细节的结构。因此，该赠款应用的一部分致力于从断层图中提取更多信息，尤其是应用于略有多态性的，结构上未知的风疹病毒。 由于它们在基因顺序和形态上的相似性，α病毒和风疹病毒构成了togavirus家族。在甲状腺病毒中，基孔肯雅病毒是世界健康的主要关注，因为它最近在亚洲和非洲重新出现。我们计划扩展我们先前对二十面体，含有α病毒的脂质的研究，并解决对多形风疹病毒的更困难的结构分析。具体而言，我们计划将基孔肯雅病毒样颗粒的分辨率扩展到近原子分辨率，使用冷冻电子显微镜在NIH疫苗研究中心与Gary Nabel一起针对Chikungunya病毒的疫苗设计。我们还计划通过分析电子断层图来确定风疹病毒的结构。 我们计划使用抗体和肽抑制剂来阻断宿主细胞的成熟，附着和融合，以研究病毒生命周期中遇到的结构中间体。我们计划确定风疹病毒成分的其余未知结构，并使用晶体学和电子显微镜研究它们相互和抗体的相互作用。 公共卫生相关性：α病毒可能是致命的人类病原体，而印度和东南亚的基孔肯雅病毒（一种α病毒）最近出现是世界卫生的主要关注点。因此，我们对抑制感染的中和抗体和肽的研究 与当前主要的健康问题有关。此外，我们的研究取决于将当前的结构技术扩展到多态病毒，从而对含有包围病毒（例如红宝石病毒，α病毒同源物）的许多脂质膜进行了可能的结构研究。