Genome packaging in DNA viruses

DNA病毒中的基因组包装

• 批准号: 7986908
• 负责人: Liang Tang
• 金额: $ 27.43万
• 依托单位: UNIVERSITY OF KANSAS LAWRENCE
• 依托单位国家: 美国
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-09-01 至 2015-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7986908
• 关键词: Address; Adenoviruses; Antiviral Agents; Bacteriophages; Binding; Binding Sites; Biochemical; Biological; Biological Models; Biological Phenomena; Biological Process; Capsid; Catalytic Domain; Categories; Chickenpox; Cleaved cell; Complex; Concatenated DNA; Cryoelectron Microscopy; DNA; DNA Binding; DNA Packaging; DNA Viruses; Data; Dimensions; Disease; Double Stranded DNA Virus; Drug Delivery Systems; Encephalitis; Future; Genome; Goals; Herpesviridae; Herpesvirus 1; Herpesvirus Type 3; Human; In Vitro; Individual; Infection; Infection prevention; Knowledge; Length; Lesion; Letters; Life; Life Cycle Stages; Link; Malignant Neoplasms; Measures; Medical; Methods; Molecular; Molecular Machines; Morphogenesis; Mutagenesis; Organ; Population; Poxviridae; Process; Proteins; Public Health; Reaction; Research; Resolution; Roentgen Rays; Role; Structural Models; Structure; System; Tail; Time; Universities; Viral; Viral Proteins; Virion; Virus; Virus Assembly; X-Ray Crystallography; design; ds-DNA; human disease; improved; interest; molecular assembly/self assembly; novel; pathogen; public health relevance; reconstitution; terminase; viral DNA

DESCRIPTION (provided by applicant): Genome packaging is a key step in morphogenesis of large double-stranded DNA (dsDNA) viruses including tailed double-stranded DNA bacteriophages and herpesviruses, and is essential for assembly of infectious progeny virions. Genome packaging is a precisely coordinated molecular synergy, in which a certain amount of viral DNA from a DNA concatemer is inserted into a preformed procapsid, followed by binding of additional viral proteins to the capsid to retain the packaged DNA. This DNA insertion process is fulfilled by a powerful molecular machine consisting of the terminase and the portal. The portal forms a conduit at a single vertex of the capsid that allows viral DNA to enter during virus assembly and exit during infection. The terminase complex contains a DNA-recognition subunit that specifically binds to the viral DNA, and a catalytic subunit that provides the energy for the packaging reaction and cleaves the genome-length DNA from the concatemer. Molecular mechanisms of genome packaging in these large viruses are not well understood, owing to unusual complexity and lack of high resolution structural data. In particular, these genome-packaging proteins have to form high-order molecular assemblies in order to function. The portal protein forms a ring-like dodecamer embedded in the capsid. However, little is known about how the terminase assembles, how it assembles with the portal, and how the portal is embedded in the capsid. Our goal is to understand molecular mechanisms of genome packaging in DNA viruses by analyzing assemblies of genome-packaging proteins using structural approaches. We are particularly interested in the general question of how numerous proteins and other biological molecules, each present in multiple copies, assemble hierarchically into a sophisticated system to fulfill a complex biological process. In the present proposal, we seek to: (i) elucidate the high resolution structure of a complete, infectious bacterial virus; (ii) elucidate structures of component proteins of the terminase; (iii) elucidate the mode of DNA-binding for a terminase DNA-recognition protein; and (iv) explore the assembly of the terminase complex in vitro. Herpes viruses are important human pathogens that cause diseases ranging from chickenpox to various forms of cancer. This proposal is anticipated to contribute to public health by identification of novel targets of antiviral to control and prevent infection and diseases caused by herpes viruses. PUBLIC HEALTH RELEVANCE: Human herpes viruses are linked to important human diseases ranging from chickenpox to life-threatening cancer. The majority of individuals in most human populations are infected by several herpes viruses. We seek to investigate a common molecular mechanism in life cycles of herpes virus and many other large double- stranded DNA viruses, in search of new measures to control and prevent infection and diseases caused by these viral pathogens.

描述（由申请人提供）：基因组包装是大型双链 DNA (dsDNA) 病毒（包括有尾双链 DNA 噬菌体和疱疹病毒）形态发生的关键步骤，并且对于感染性子代病毒粒子的组装至关重要。基因组包装是一种精确协调的分子协同作用，其中来自 DNA 串联体的一定量的病毒 DNA 被插入到预先形成的衣壳中，然后将其他病毒蛋白与衣壳结合以保留包装的 DNA。这个 DNA 插入过程是通过由终止酶和门户组成的强大分子机器来完成的。该入口在衣壳的单个顶点形成管道，允许病毒 DNA 在病毒组装期间进入并在感染期间退出。终止酶复合物包含一个特异性结合病毒 DNA 的 DNA 识别亚基，以及一个为包装反应提供能量并从多联体上切割基因组长度 DNA 的催化亚基。由于异常复杂性和缺乏高分辨率结构数据，这些大型病毒基因组包装的分子机制尚不清楚。特别是，这些基因组包装蛋白必须形成高阶分子组装体才能发挥作用。门蛋白形成嵌入衣壳中的环状十二聚体。然而，人们对终止酶如何组装、如何与门户组装以及门户如何嵌入衣壳中知之甚少。我们的目标是通过使用结构方法分析基因组包装蛋白的组装来了解 DNA 病毒基因组包装的分子机制。我们对这样一个普遍问题特别感兴趣：大量的蛋白质和其他生物分子（每种都以多个副本存在）如何分层组装成一个复杂的系统来完成复杂的生物过程。在本提案中，我们寻求：（i）阐明完整的传染性细菌病毒的高分辨率结构； (ii) 阐明终止酶的组成蛋白的结构； (iii) 阐明 DNA 终止酶识别蛋白的 DNA 结合模式； (iv) 探索末端酶复合物的体外组装。疱疹病毒是重要的人类病原体，可引起从水痘到各种癌症的疾病。该提案预计将通过确定新的抗病毒靶点来控制和预防疱疹病毒引起的感染和疾病，从而为公共卫生做出贡献。 公共卫生相关性：人类疱疹病毒与从水痘到危及生命的癌症等重要的人类疾病有关。大多数人群中的大多数人都感染了几种疱疹病毒。我们寻求研究疱疹病毒和许多其他大型双链DNA病毒生命周期中的共同分子机制，寻找控制和预防这些病毒病原体引起的感染和疾病的新措施。