Mechanisms in Polyomavirus Assembly

项目摘要 病毒学中的一个新兴概念是病毒复制和病毒体组装通常是机械性的。 偶联在细胞内称为病毒“工厂”的特定位置。的空间和时间 这些过程的协调允许病毒体的装配线生产， 能量上有利，同时允许最终结构的质量控制。虽然工厂 已经详细描述了在细胞质中复制的病毒，大多数DNA病毒 在细胞核中复制/组装，其中工厂的形态特征难以识别 并由于密集的染色质网络而进行表征。也有迹象表明， 篡夺必需的核结构域，否则用于诸如DNA损伤修复（DDR）的功能， 事实上，在DNA病毒的复制位点发现了许多参与DDR的细胞蛋白。我们 建议对病毒粒子组装工厂的结构和组成进行表征， 使用iPOND蛋白鉴定的组合方法， 分辨率成像和病毒/宿主细胞遗传学。我们的目标是确定 这些工厂在纳米分辨率以及空间和功能的关系， 蛋白质成分随着10种新的人类多瘤病毒的鉴定， 随着用于多种疾病的免疫调节疗法的增加，多瘤病毒已经出现， 重要的人类病原体，目前没有特异性治疗。表征 组装工厂不仅将确定影响多瘤病毒复制的新治疗靶点， 以及其他DNA病毒，而且还提供了关于它们在正常细胞过程中的功能的见解。

PROJECT SUMMARY An emerging concept in virology is that viral replication and virion assembly are often mechanistically coupled in specific locations within the cell at sites termed virus “factories”. The spatial and temporal coordination of these processes permit assembly line production of virions in a manner that is energetically favorable while allowing for quality control of the final structure. Although factories have been described in some detail for viruses replicating in the cytoplasm, most DNA viruses replicate/assemble in the nucleus where morphological features of factories are problematic to identify and characterize due to the dense chromatin network. There are also indications that the factories usurp essential nuclear domains otherwise used for such functions as DNA damage repair (DDR), and indeed many cellular proteins involved in DDR are found at replication sites for DNA viruses. We propose to characterize the structure and composition of virion assembly factories for the well-studied murine polyomavirus using a combined approach employing iPOND protein identification, high resolution imaging, and virus/host cell genetics. Our goal is to determine the molecular architecture of these factories at nanometer resolution as well as the spatial and functional relationships of their protein components. With the recent identification of ten new human polyomaviruses, and the marked increase in immunomodulatory therapies for a variety of diseases, polyomaviruses have emerged as important human pathogens that at present have no specific therapy. Characterization of the assembly factories not only will identify new therapeutic targets for affecting polyomavirus replication, as well as other DNA viruses, but also provide insight as to their function in normal cellular processes.