The Cell Biology of Coronavirus Infection

描述（由申请人提供）：冠状病毒是一种正链RNA病毒，可引起人类呼吸道感染和其他动物重要的胃肠道和神经系统疾病。小鼠肝炎病毒（MHV）是研究冠状病毒复制和发病机制的模型。本研究的中心目标是确定小鼠肝炎病毒与宿主细胞在病毒复制复合体形成和功能过程中的相互作用。MHV在分布在细胞质中的膜复制复合体上指导病毒RNA合成。这些复合体不同于病毒粒子在高尔基体中间区室（ERGIC）的组装位点。复制酶基因多蛋白加工后的蛋白与核衣壳(N)蛋白一起定位于病毒RNA合成的两个密切相关的蛋白复合物，p22/p65复合物和hel/N复合物。在感染后期，hel/N复合物与p22/p65复合物分离，并转移到ERGIC中的病毒粒子组装位点。然而，复制复合体的精确组成尚不清楚，hel/N复合体易位的机制也尚未确定。本提案描述了一个综合的研究计划，以定义MHV复制复合体的组织和易位。在特异性目的1中，将确定MHV复制复合体的蛋白质和膜组成。在具体目标2中，将定义hel/N复合物转运到ERGIC的机制。在特异性目标3中，将确定病毒蛋白在复制复合体易位中的功能。这些研究将确定MHV指导复制复合体形成和功能的基本机制，并将确定对病毒成功复制至关重要的病毒-细胞相互作用。

DESCRIPTION (provided by applicant): Coronaviruses are positive-strand RNA viruses that cause respiratory infections in humans and important gastrointestinal and neurologic disease in other animal species. Mouse hepatitis virus (MHV) is a model for studies of coronavirus replication and pathogenesis. The central goal of the proposed research is to define interactions of mouse hepatitis virus with host cells during formation and function of viral replication complexes. MHV directs viral RNA synthesis on membranous replication complexes that are distributed thoughout the cytoplasm. These complexes are distinct from sites of virion assembly in the intermediate compartment of the Golgi (ERGIC). Proteins processed from the replicase gene polyprotein localize with the nucleocapsid (N) protein at sites of viral RNA synthesis in two closely associated protein complexes, the p22/p65 complex and the hel/N complex. At late times of infection, the hel/N complexes separate from the p22/p65 complexes and translocate to sites of virion assembly in the ERGIC. However, the precise composition of replication complexes is not known, and the mechanism of hel/N complex translocation has not been determined. This proposal describes an integrated research program to define the organization and translocation of MHV replication complexes. In Specific Aim 1, the protein and membrane composition of MHV replication complexes will be determined. In Specific Aim 2, the mechanism of hel/N complex translocation to the ERGIC will be defined. In Specific Aim 3, the functions of viral proteins in replication complex translocation will be determined. These studies will identify fundamental mechanisms by which MHV directs replication complex formation and function and will define virus-cell interactions that are essential for successful virus replication.