5' End Genomic Deletions and Enterovirus Persistence

5 端基因组缺失和肠道病毒持久性

• 批准号: 8206597
• 负责人: Nora M. Chapman
• 金额: $ 29.4万
• 依托单位: UNIVERSITY OF NEBRASKA MEDICAL CENTER
• 依托单位国家: 美国
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-01-15 至 2013-12-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8206597
• 关键词: Acute; Adult; Affect; Binding; Binding Sites; Biology; Cell Culture Techniques; Cell Nucleus; Cells; Child; Chronic; Chronic Disease; Complex; Coxsackie B Viruses; Cytoplasm; Dilated Cardiomyopathy; Disease; Enterovirus; Enterovirus Infections; Environment; Etiology; Event; Family Picornaviridae; Generations; Genome; Genomics; Goals; Growth; Heart; Heart Diseases; Higher Order Chromatin Structure; Human; Human poliovirus; Immune; Immune response; Infection; Knowledge; Laboratories; Lead; Life Style; Link; Long-Term Effects; Lytic; Mus; Mutate; Myocarditis; Nuclear; Nucleotides; Pancreatic Diseases; Polioviruses; Population; Primary Cell Cultures; Process; Production; Proteins; RNA; RNA Viruses; RNA chemical synthesis; RNA replication; Reporting; Role; Serotyping; Site; Time; Tissues; Variant; Viral; Viral Physiology; Virion; Virus; Work; base; fascinate; heart function; human disease; insight; nervous system disorder; novel; protein structure; public health relevance; sound; viral RNA; viral detection

DESCRIPTION (provided by applicant): The mutable RNA viruses are marvelously successful at adapting to exploit new environments. We will explore just such a newly discovered adaptation in this project, determining how the loss of a genomic region that is vital to replicational efficiency, allows an enterovirus to adapt to a different intracellular environment. Enteroviruses have been viewed as characteristically rapidly lytic, causing short-term infections. However, the discovery that group B coxsackieviruses (CVB) can delete sequence from the genomic 5' terminus (TD), yet maintain function and most importantly, persist for long periods of time post-infection in the heart or cell culture, has provided the grist with which to challenge that traditional view. Given that the 5' terminus of enterovirus RNA is involved in numerous functions for viral replication, deletion of as many as 49 nucleotides from the 5' end of the genome should be a dire event for the virus and indeed, it is. Among other things, viral replication slows dramatically and crippled positive strand RNA synthesis results in near 1 to 1 levels of positive to negative viral RNA in infected cells. The objective of this proposal is to characterize the role of hnRNPC1 in the mechanism by which CVB-TD populations become established. We hypothesize that under circumstances defined by the host cell - a lack of cytoplasmic hnRNPC1 in quiescent cells - an alternative form of positive strand viral RNA synthesis initiation occurs that leads to 5' end deletions of the positive strand genome. A single specific aim is proposed to accomplish this objective: we will determine whether a range of a terminal deletions occurs in quiescent cells due to altered viral transcriptional initiation, whether that range is limited by a requirement for part of structural domain I of the 5'nontranslated region and we will examine the structure and proteins of the CVB-TD replication complex. We will determine how selective lowering of cytoplasmic hnRNPC1 affects wildtype and TD CVB replication, if hnRNPC1 fails to bind the mutated 3' terminus of CVB- TD negative strand RNA and to what extent the wildtype process of uridylylation of the enterovirus protein primer is involved in CVB3-TD initiation of positive strand RNA synthesis. Cumulatively, this work will significantly expand our knowledge of this fascinating enterovirus lifestyle, providing insight into a novel mechanism by which enteroviruses can persist and cause chronic disease in humans. PUBLIC HEALTH RELEVANCE: This study is to determine the conditions and processes for generation of persistent enterovirus infections. These infections in hearts are associated with long term effects upon heart function including debilitating conditions such as dilated cardiomyopathy and chronic myocarditis. Understanding how selection of these variant viruses occurs and how these viruses replicate will provide the basis for developing treatments and detection of these viruses in heart, neurological and pancreatic disease.

描述（由申请人提供）：可变RNA病毒在适应新环境方面非常成功。我们将在这个项目中探索这种新发现的适应，确定对复制效率至关重要的基因组区域的丢失如何允许肠道病毒适应不同的细胞内环境。肠道病毒被认为具有快速裂解的特征，可引起短期感染。然而，发现B组柯萨奇病毒（CVB）可以从基因组5'末端（TD）缺失序列，但仍保持功能，最重要的是，在心脏或细胞培养物中感染后长时间持续存在，这为挑战传统观点提供了依据。考虑到肠道病毒RNA的5'末端参与病毒复制的许多功能，从基因组的5'末端缺失多达49个核苷酸对于病毒来说应该是一个可怕的事件，事实也确实如此。除此之外，病毒复制显著减慢，并且受损的正链RNA合成导致感染细胞中阳性与阴性病毒RNA的水平接近1比1。该建议的目的是表征hnRNPC 1在CVB-TD群体建立的机制中的作用。我们假设在宿主细胞定义的情况下-静止细胞中缺乏胞质hnRNPC 1-发生另一种形式的正链病毒RNA合成起始，导致正链基因组的5'端缺失。提出了一个单一的具体目标，以实现这一目标：我们将确定是否一系列的末端缺失发生在静止细胞由于改变病毒转录起始，是否该范围是有限的5 '非翻译区的结构域I的一部分的要求，我们将检查CVB-TD复制复合物的结构和蛋白质。我们将确定如果hnRNPC 1不能结合CVB-TD负链RNA的突变的3'末端，细胞质hnRNPC 1的选择性降低如何影响野生型和TD CVB复制，以及肠病毒蛋白引物的尿苷酰化的野生型过程在多大程度上参与CVB 3-TD正链RNA合成的起始。累积起来，这项工作将显着扩大我们对这种迷人的肠道病毒生活方式的了解，提供对肠道病毒可以持续存在并导致人类慢性疾病的新机制的深入了解。 公共卫生相关性：本研究旨在确定产生持续性肠道病毒感染的条件和过程。这些心脏感染与对心脏功能的长期影响有关，包括使人衰弱的疾病，如扩张型心肌病和慢性心肌炎。了解这些变异病毒的选择如何发生以及这些病毒如何复制将为开发治疗和检测心脏，神经和胰腺疾病中的这些病毒提供基础。