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复制和规避控制病毒复制的细胞先天策略至关重要。其中重要的逆转录病毒蛋白是慢病毒Rev。Rev蛋白定位于受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，以完成复制。然而，人类免疫缺陷病毒1型（HIV-1）Rev最近被重新审视，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已被证明为Rev。此外，HIV-1 Rev被证明与大量的细胞蛋白质相互作用，其中大部分是细胞质或细胞核来源。到目前为止，HIV-1和牛免疫缺陷病毒（BIV）的结构域已被研究和表征最多。核仁是一种动态的细胞亚核结构，它不仅参与核糖体亚基的生物合成，而且还参与细胞应激反应的介导和细胞生长的调控。核仁的蛋白质组和结构不断变化，以响应各种代谢条件，包括近年来与病毒感染相关的代谢条件。某些DNA和RNA病毒与核仁相互作用，并招募可能在其复制中起作用的核仁蛋白。虽然慢病毒Rev在感染细胞的核仁中积累，但这种核仁定位的意义尚不清楚。由于我们证明了BIV Rev结构域的特殊结构，我们将能够解决后一点。考虑到Jembrana病病毒（JDV，一种诱导急性感染的牛慢病毒，与BIV相关的慢性和大部分无症状感染相比）和猫免疫缺陷病毒（FIV，与慢性感染相关）相关的临床症状感染的特定特征，将确定这些病毒Rev的结构域。同样重要的是，该研究计划还将关注慢病毒Rev和核仁蛋白之间的相互作用及其对病毒复制的影响。关于病毒与核仁之间的相互作用及其对病毒复制和生物发生的影响的研究正处于萌芽研究阶段。因此，这项研究计划是病毒学领域的创新，研究病毒-核仁相互作用可能有助于设计新的抗病毒疗法，并将有助于更多地了解病毒和核仁之间的密切关系，以及核仁本身的生物学。重要的是，它也将有可能将这里开发的技术和诀窍应用于其他病毒系统。

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 thedesign of novel antiviral therapies and will contributeto a much more understanding of the intimate relationships betweenviruses 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.