VIF Anatagonists: Antiviral Evaluation in Vitro, Inhibitor resistance and Mole

Vif是灵长类慢病毒如HIV-1和SIV在体内复制所必需的。在过去的两年里， 对Vif支持病毒复制的机制已经有了相当多的了解。 Vif抵消胞苷脱氨酶apobec 3G和3F的抗病毒作用。为了抑制病毒复制， 这些胞苷脱氨酶必须包装在病毒粒子内，在那里它们编辑新生病毒的负链， 在靶细胞中的cDNA。Vif通过促进apobec 3G和3F的抗病毒活性来抵消apobec 3G和3F的抗病毒活性。 蛋白酶体降解到不足以包装成病毒体的程度。 该项目的总体目标是鉴定和开发Vif拮抗剂，可用于评估 Vif拮抗作用在体内的抗病毒影响。项目2将优先考虑Vif拮抗剂， 基于抗病毒活性和特异性的项目1的抑制剂筛选。由于最有利的Vif 拮抗剂将在SIV发病机理和SIV诱导的脑炎的猕猴模型中进行评价， 将在与CNS感染相关的细胞即原代巨噬细胞中评价抗病毒活性。 项目2还将评估体外和体内抑制剂逃逸的机制。项目的主要活动 2包括： 在表达apobec的细胞（非允许细胞）和 不表达apobec的细胞（允许细胞）。 体外CNS相关靶细胞（即原代巨噬细胞）中的抗病毒活性评价。 通过评估Vif拮抗剂对病毒体的影响来鉴定Vif拮抗作用的机制 apobec的修饰和apobec介导的病毒cDNA编辑。 鉴定Vif中在体外和体内赋予抑制剂抗性的突变。 总的来说，这些研究将使我们能够确定最有前途的先导Vif拮抗剂，并优先考虑 选择抑制剂，将在SIV复制和SIV诱导的实验模型中进行评价 猕猴的脑炎

Vif is essential to the replication of primate lentiviruses such as HIV-1 and SIV in vivo. In the last two years, a considerable amount of insight has been gained into the mechanism by which Vif supports viral replication. Vif counteracts the antiviral effects of the cytidine deaminases apobec 3G and 3F. To inhibit viral replication, these cytidine deaminases must be packaged within virions where they edit the minus strand of nascent viral cDNA in the target cell. Vif counteracts the antiviral activity of apobec 3G and 3F by promoting their proteasomal degradation to the extent that there are insufficient levels for packaging into virions. The overall goal of this project is to identify and develop Vif antagonists that can be used to assess the antiviral impact of Vif antagonism in vivo. Project 2 will prioritize Vif antagonists that emerge from the inhibitor screen of Project 1 on the basis of antiviral activity and specificity. Since the most favorable Vif antagonists will be evaluated in the macaque model of SIV pathogenesis and SIV-induced encephalitis, antiviral activity will be evaluated in cells that are relevant to CNS infection namely, primary macrophages. Project 2 will also assess mechanisms of inhibitor escape in vitro and in vivo. The major activities of Project 2 include: Evaluation of antiviral activity and specificity in cells that express apobec (non-permissive cells) and cells that do not express apobec (permissive cells). Evaluation of antiviral activity in CNS-relevant target cells in vitro, namely, primary macrophages. Identification of the mechanism of Vif antagonism by assessing impact of Vif antagonists on virion encapsidation of apobec and on apobec-mediated editing of viral cDNA. Identification of mutations in Vif that confer inhibitor resistance in vitro and in vivo. Collectively, these studies will allow us to identify the most promising lead Vif antagonists and prioritize the selection of inhibitors that will be evaluated in an experimental model of SIV replication and SIV-induced encephalitis in macaques.