Viral Modulation of Genetic Stability

遗传稳定性的病毒调节

• 批准号: 8196815
• 负责人: Matthew D. Weitzman
• 金额: $ 28.95万
• 依托单位: CHILDREN'S HOSP OF PHILADELPHIA
• 依托单位国家: 美国
• 财政年份: 2003
• 资助国家: 美国
• 起止时间: 2003-04-01 至 2013-11-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8196815
• 关键词: ATM Signaling Pathway; ATM activation; Address; Adenovirus Infections; Adenoviruses; Affect; Antiviral Agents; Biochemical; Biological; Biological Assay; Cell physiology; Cells; Complex; DNA; DNA Damage; DNA Repair; DNA Repair Pathway; DNA Viruses; DNA biosynthesis; DNA repair protein; DNA-PKcs; Data; Double Strand Break Repair; Excision; Funding; Genetic; Genome; Host Defense; Infection; Lead; Ligase; Link; Mammalian Cell; Measures; Modeling; Nuclear; Oncogenic; Open Reading Frames; Pathway interactions; Pattern; Phosphotransferases; Play; Prevention; Production; Protein Biosynthesis; Protein p53; Proteins; Recruitment Activity; Role; Serotyping; Signal Transduction; Structure; Testing; Viral; Viral Genome; Viral Proteins; Virus; Virus Diseases; Virus Replication; Xenopus; adenovirus terminal protein; cellular targeting; human NBS1 protein; in vitro Assay; insight; multicatalytic endopeptidase complex; mutant; prevent; protein complex; repaired; response; sensor; ubiquitin ligase; ubiquitin-protein ligase; viral DNA

Project Summary Viruses elicit multifaceted responses from the cells that they infect. Among the antiviral defenses of the host cell is activation of a DNA damage response. In the case of adenovirus (Ad) infection, the double-stranded, linear DNA genomes represent substrates for cellular DNA repair pathways that result in Ad genomes being joined into concatemers during infection with viruses deleted of the E4 open reading frames. Concatemerization requires host DNA repair proteins, including the Mre11/Rad50/Nbs1 complex (MRN). Infection with E4-deleted Ad is accompanied by activation of the cellular DNA damage signaling cascades. The DNA damage response is inactivated during wild-type Ad infection by the products of the early region E4. The E4orf3 protein forms intranuclear track structures, which sequester the MRN proteins and prevent ATR damage signaling. The E4orf6 protein forms a complex with E1b55K that recruits cellular proteins to form an E3 ligase that targets cellular repair factors for degradation, including MRN and ligase IV proteins. This proposal probes mechanistic aspects of the cellular response to adenovirus infection and its impact on the viral lifecycle. We show that MRN inhibits virus DNA replication, identify a role for the CtIP protein, and suggest a model that involves removal of the terminal protein from the virus genome. In the first Aim we will address the impact of the cellular repair proteins on virus infection and test the model for inhibition. The subsequent two Aims will address ways in which E4 proteins counteract these host antiviral functions. In Aim 2 we will study the mechanism used by E1b55K/E4orf6 to target cellular factors for proteasomal degradation, and the impact on virus replication. Aim 3 will focus on Ad E4orf3, and will investigate the correlation between disruption of PML bodies, mis-localization of the MRN complex, prevention of concatemer formation, inhibition of damage signaling, and production of late proteins by E4orf3. These studies will elucidate the biological relevance of the interactions between cellular repair factors and viral proteins, and will have broader implications for our understanding of cellular DNA damage responses.

项目摘要 病毒会从它们感染的细胞中引发多方面的反应。在宿主的抗病毒防御中 细胞是DNA损伤反应的激活。在腺病毒（Ad）感染的情况下，双链， 线性DNA基因组代表细胞DNA修复途径的底物， 在感染E4开放阅读框缺失的病毒时连接成多联体。 串联需要宿主DNA修复蛋白，包括Mre 11/Rad 50/Nbs 1复合物（MRN）。 E4缺失的Ad感染伴随着细胞DNA损伤信号级联的激活。 在野生型Ad感染期间，DNA损伤反应被早期区域E4的产物灭活。 E4 orf 3蛋白形成核内轨道结构，其隔离MRN蛋白并防止ATR 损坏信号E4 orf 6蛋白与E1 b55 K形成复合物，该复合物募集细胞蛋白以形成一个蛋白质。 E3连接酶，靶向降解细胞修复因子，包括MRN和连接酶IV蛋白。 该提案探讨了细胞对腺病毒感染的反应机制及其对细胞增殖的影响。 病毒生命周期我们表明，MRN抑制病毒DNA复制，确定CtIP蛋白的作用， 提出了一种模型，涉及从病毒基因组中去除末端蛋白。在第一个目标中，我们将 解决细胞修复蛋白对病毒感染的影响，并测试抑制模型。的 随后的两个目标将解决E4蛋白抵消这些宿主抗病毒功能的方法。在Aim中 2.我们将研究E1 b55 K/E4 orf 6靶向细胞因子降解蛋白酶体的机制， 以及对病毒复制的影响。目标3将重点关注Ad E4 orf 3，并调查以下内容之间的相关性 破坏PML小体，MRN复合物的错误定位，防止多联体形成，抑制 损伤信号传导和E4 orf 3晚期蛋白的产生。这些研究将阐明 细胞修复因子和病毒蛋白之间相互作用的相关性，并将有更广泛的 对我们理解细胞DNA损伤反应的影响。