Sindbis nonstructural protein nsP2: Interaction with cellular proteins

描述（由申请人提供）：该项目代表了我们对甲病毒复制和与细胞相互作用机制的持续研究。辛德毕斯病毒（SINV）是在分子和细胞水平上研究与甲病毒复制和发病机制有关的基本问题的最有价值的工具。然而，尽管几个研究小组做出了巨大努力，我们对这些过程的了解还远远不够。SINV非结构蛋白nsP 2不仅是复制复合物（replicative complex，RC）的一个组成部分，而且还分布在RC外的细胞质中，并以高浓度存在于感染细胞的细胞核中。我们假设，我们的初步数据的基础上，SINV nsP 2起着关键作用，不仅在处理病毒的非结构蛋白和合成病毒特异性RNA，但也在控制病毒诱导的应激反应的发展，通过抑制细胞基因的转录。因此，这种蛋白质是在SINV复制期间细胞病变效应的发展和抗病毒细胞应答的下调中关键参与的病毒因子之一。我们的具体目标是：1.鉴定SINV nsP 2在不同细胞区室中形成的蛋白复合物。2.研究nsP 2结合蛋白的生物学功能。3.确定在病毒-宿主细胞相互作用中起关键作用的SINV nsP 2结构域和序列。本申请的结果将提供关于SINV nsP 2与不同细胞区室中的细胞蛋白相互作用的详细信息。我们将产生新的数据，细胞蛋白质的功能，在SINV复制和阐明机制的干扰SINV复制细胞转录。使用各种方法，我们将分析这些数据的生物学意义，并确定nsP 2结构域和序列，这是关键的nsP 2在病毒-宿主细胞相互作用的功能。这些信息将促进我们在细胞水平上对SINV发病机制的理解，并且不仅适用于SINV，而且适用于其他旧世界甲病毒。所鉴定的与SINV nsP 2相互作用并参与SINV RC形成和细胞转录抑制的宿主蛋白可用作抗病毒治疗的靶点。 甲病毒是一组广泛分布的人类和动物病原体;其中一些引起高度衰弱的疾病，在美国是一种严重的公共卫生治疗。本申请的目的是阐明一种病毒非结构蛋白在抑制抗病毒反应中的作用。了解干扰抗病毒反应的病毒特异性机制将导致新的抗病毒治疗策略的发展。

DESCRIPTION (provided by applicant): This project represents our continuing investigation into the mechanism of alphavirus replication and interaction with cells. Sindbis virus (SINV) is the most valuable tool for examining fundamental issues pertaining to alphavirus replication and pathogenesis on the molecular and cellular levels. However, despite great efforts by several research groups, our knowledge of these processes is far from complete. SINV nonstructural protein nsP2 is not only a component of the replicative complexes (RCs), but is also distributed in the cytoplasm outside of the RCs and is present at high concentrations in the nuclei of infected cells. We hypothesize, on the basis of our preliminary data, that SINV nsP2 plays critical roles not only in the processing of viral nonstructural proteins and synthesis of virus-specific RNAs, but also in controlling the development of the virus-induced stress response by inhibiting transcription of cellular genes. Thus, this protein is one of the viral factors critically involved in development of cytopathic effect and downregulation of the antiviral cell response during SINV replication. Our specific aims are: 1. To identify protein complexes formed by SINV nsP2 in different cellular compartments. 2. To study biological functions of the nsP2-binding cellular proteins. 3. To identify domains and sequences in SINV nsP2 playing critical roles in virus-host cell interactions. The results of this application will provide detailed information about the interaction of SINV nsP2 with cellular proteins in different cellular compartments. We will generate new data about the functions of cellular proteins in SINV replication and elucidate the mechanism of interference of SINV replication with cellular transcription. Using a variety of approaches, we will analyze the biological significance of these data and identify the nsP2 domains and sequences that are critical in the functioning of nsP2 in virus-host cell interactions. This information will advance our understanding of SINV pathogenesis on cellular level, and it will be mostly applicable, not only to SINV, but also to other Old World alphaviruses. The identified host proteins interacting with SINV nsP2 and involved in SINV RC formation and inhibition of cellular transcription might be used as targets for the antiviral therapy. Alphaviruses is a group of widely distributed human and animal pathogens; some of them induce highly debilitating diseases and represent a serious public health treat in the US. The goal of this application is to elucidate the role of one of the viral nonstructural protein in suppression of the antiviral response. Understanding of the virus-specific mechanisms of interference with antiviral response will lead to development of new antiviral therapeutic strategies.