Lentivirus Rev protein: characterization and study of Rev - nucleolar protein interactions

定义宿主细胞和病毒蛋白之间的相互作用对于理解病毒如何利用细胞功能进行复制和规避控制病毒复制的细胞固有策略至关重要。在重要的逆转录病毒蛋白中，慢病毒Rev蛋白定位于被感染细胞的细胞核和核仁。Rev的主要功能是将未剪接和单剪接的病毒转录本从细胞核转运到细胞质中完成复制。然而，最近对人类免疫缺陷病毒1型（HIV-1） Rev进行了重新研究，并证明了Rev的其他功能，如调节细胞基因组内的病毒基因组整合和参与病毒组装。此外，HIV-1 Rev被证明与大量细胞蛋白相互作用，其中大多数是细胞质或细胞核起源的。迄今为止，对HIV-1和牛免疫缺陷病毒（BIV）的结构域研究最多。

Defining interactions between host cells and viral proteins is essential in understanding how viruses exploit cellular functions to replicate and circumvent the cell innate strategies underlying the control of virus replication. Among important retroviral proteins is the lentiviral Rev. The Rev protein localizes to the nuclei and nucleoli of infected cells. Rev main function is to transport from the nucleus to the cytoplasm the unspliced and singly spliced viral transcripts to fullfil replication. However, the Human immunodeficiency virus type 1 (HIV-1) Rev was recently revisited and other functions such as regulating viral genome integration within the cell genome and participating in virus assembly have been demonstrated for Rev. In addition, HIV-1 Rev was shown to interact with a significant number of cellular proteins the majority of which were of cytoplasmic or nucleus origin. So far structural domains of HIV-1 and the Bovine immunodeficiency virus (BIV) have been the most studied and characterized. The nucleolus is a dynamic cell subnuclear structure with roles not only in ribosome subunit biogenesis, but also in mediation of cell-stress response and regulation of cell growth. The proteome and structure of the nucleolus are constantly changing in response to various metabolic conditions including those that have been associated in the recent years with viral infections. Certain DNA and RNA viruses interact with the nucleolus and recruit nucleolar proteins that may have a role in their replication. Although lentivirus Rev accumulate in the nucleoli of infected cells, the significance of this nucleolar localization is unclear. Because of the particular structure demonstrated by us for the BIV Rev domains, we will be able to address the latter point. Given the particular characteristics of the infections with clinical symptoms associated to the Jembrana disease virus (JDV, a bovine lentivirus inducing an acute infection in comparison of the BIV-associated chronic and mostly asymptomatic infection) and the Feline immunodeficiency virus (FIV associated to a chronic infection), the structural domains of Rev of these viruses will be determined. As importantly the research proposal will also focuss on the interactions between the lentiviral Rev and nucleolar proteins and their impact in viral replication. Studies on interactions between viruses and the nucleolus and their impact on virus replication and biogenesis are at the embryonic research stage. Thus this research program is innovative for the virology field and investigating virus-nucleolus interactions may facilitate the design of novel antiviral therapies and will contribute to a much more understanding of the intimate relationships between viruses and nucleolus, and also of the biology of the nucleolus itself. Importantly it will also be possible to apply the technology and know-how developed here to other virus systems.