The roles of acidic autophagosomes in production of infectious poliovirus

酸性自噬体在传染性脊髓灰质炎病毒产生中的作用

• 批准号: 9237187
• 负责人: William T Jackson
• 金额: $ 38.2万
• 依托单位: UNIVERSITY OF MARYLAND BALTIMORE
• 依托单位国家: 美国
• 财政年份: 2014
• 资助国家: 美国
• 起止时间: 2014-04-01 至 2019-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9237187
• 关键词: Appearance; Autophagocytosis; Autophagosome; Capsid Proteins; Cell membrane; Cells; Cellular Membrane; Cellular Stress; Characteristics; Cytosol; Data; Development; Encapsulated; Environment; Enzymes; Extracellular Space; Family; Family Picornaviridae; Future; Generations; Genome; Goals; Homeostasis; Human; Human poliovirus; Infection; Lead; Life Cycle Stages; Lysosomes; Medical; Membrane; Modeling; Monitor; Morphogenesis; Morphology; Nature; Organelles; Outcome; Pathway interactions; Play; Process; Production; Proliferating; Proteins; Proteome; Proteomics; RNA; RNA Viruses; RNA replication; Research; Role; Signal Transduction; Site; Testing; Therapeutic; Therapeutic Agents; Time; Transport Vesicles; Vesicle; Vesicle Transport Pathway; Viral; Virion; Virus; Virus Diseases; Virus Replication; Work; biological adaptation to stress; experimental study; genomic RNA; human disease; innovation; insight; novel; pathogen; phosphatidylinositol 4-phosphate; prevent; public health relevance; therapeutic target; viral RNA

DESCRIPTION (provided by applicant): All positive strand RNA viruses studied to date rearranged cellular membranes to promote their own replication. One reason for these rearrangements is that these viruses replicate their genomic RNA in association with cellular membranes. In poliovirus (PV), a model for a host of medically important positive strand RNA viruses, two distinct classes of vesicle have been identified. One class, a single-membraned vesicle which resembles a COPII secretory transport vesicle, associates with viral RNA replication proteins. The second type of vesicle, which is double-membraned, also associates with viral RNA replication proteins and resembles the autophagosome, an organelle induced by a pathway of cellular homeostasis and stress-response known as autophagy. Autophagosome-like vesicles are specifically induced by viruses and promote PV production. The long term goal of this project is to understand the mechanisms and consequences of cellular membrane rearrangements by picornaviruses. The objective of this application is to identify the roles played by autophagosomes during infection and define the mechanism by which PV induces autophagosome morphogenesis. Our preliminary data indicate that autophagy is required for optimal levels of infectious virus. Autophagic signaling is required for viral RNA replication. However, vesicle acidification, which in the case of autophagosomes is required for fusion with lysosomes, is required for cleavage of a viral capsid protein, the final step in generating infectious virus from newly formed virions. The central hypothesis of this proposal is that PV infection generates autophagosomes through morphological changes, including invagination, in the PIP4-rich secretory pathway-derived vesicles used for RNA replication. Acidification of the newly formed autophagosomes promotes virion maturation. The central hypothesis will be tested by pursuing two specific aims. In Aim I we will study the nature of the vesicle environment, and the requirements for virion maturation. In Aim II we will analyze the development of autophagic vesicles during infection and define the proteome of virus-induced autophagosomes. The rationale for this research is to understand how picornaviruses subvert what is often an anti-pathogen pathway to promote virion maturation. This will provide us with information needed to target this late step in virus production with therapeutics. Our innovative approaches will identify the mechanisms PV uses to induce autophagosomes, and how they promote maturation and egress of infectious virus. The proposed research is significant because it will fundamentally advance our understanding of how a medically important family of viruses subverts a basic cellular pathway to promote virus replication. This work will provide novel insights into the late stages of the viral life cycle, especially maturation and cellular egress, and provide the first steps in identifying therapeutic targets that may ultimately lead to treatments against multiple viral diseases. This work is also an important step in understanding the mechanisms of existing and future therapeutic agents against multiple viral diseases.

描述（由申请方提供）：迄今为止研究的所有正链RNA病毒均重排细胞膜以促进自身复制。这些重排的一个原因是这些病毒复制它们的基因组RNA与细胞膜相关。在脊髓灰质炎病毒（PV）中，一种医学上重要的正链RNA病毒宿主的模型，已经鉴定出两种不同类型的囊泡。一类是类似于COPII分泌运输囊泡的单膜囊泡，与病毒RNA复制蛋白相关。第二种囊泡是双膜的，也与病毒RNA复制蛋白相关，类似于自噬体，自噬体是一种由称为自噬的细胞稳态和应激反应途径诱导的细胞器。自噬体样囊泡由病毒特异性诱导并促进PV产生。本项目的长期目标是了解小核糖核酸病毒引起的细胞膜重排的机制和后果。此应用程序的目的是确定所扮演的角色 通过自噬体感染，并定义PV诱导自噬体形态发生的机制。我们的初步数据表明，自噬是感染性病毒的最佳水平所必需的。自噬信号是病毒RNA复制所必需的。然而，在自噬体的情况下与溶酶体融合所需的囊泡酸化是病毒衣壳蛋白裂解所需的，这是从新形成的病毒体产生感染性病毒的最后一步。该提议的中心假设是，PV感染通过形态学变化（包括内陷）在用于RNA复制的富含PIP 4的分泌途径衍生的囊泡中产生自噬体。新形成的自噬体的酸化促进病毒粒子成熟。中心假设将通过追求两个具体目标来检验。在目的一，我们将研究囊泡环境的性质，和病毒粒子成熟的要求。在目的II中，我们将分析感染过程中自噬囊泡的发展，并定义病毒诱导的自噬体的蛋白质组。这项研究的基本原理是了解小核糖核酸病毒如何破坏通常的抗病原体途径，以促进病毒粒子成熟。这将为我们提供所需的信息，以靶向治疗病毒生产的这一后期步骤。我们的创新方法将确定PV用于诱导自噬体的机制，以及它们如何促进感染性病毒的成熟和排出。这项拟议中的研究意义重大，因为它将从根本上推进我们对医学上重要的病毒家族如何颠覆基本细胞途径以促进病毒复制的理解。这项工作将为病毒生命周期的后期阶段提供新的见解，特别是成熟和细胞出口，并提供确定治疗靶点的第一步，这些靶点最终可能导致针对多种病毒疾病的治疗。这项工作也是了解现有和未来治疗药物对抗多种病毒性疾病的机制的重要一步。