Understanding Retroviral Gag and RNA Targeting and Virus Assembly

我们已经研究了产生传染性病毒所需的复杂相互作用。我们发现来自两种慢病毒（HIV-1和SIVmac）的成熟衣壳蛋白可以组装成感染性颗粒的成熟核心。此外，我们量化了HIV-1感染期间所需的功能性核衣壳（NC）和p6蛋白的数量，并确定了用次优浓度的蛋白酶抑制剂治疗HIV-1对病毒蛋白加工和RNA成熟的影响。我们将研究HIV-1大分子的贩运和组装。一旦从细胞核输出，HIV-1 RNA需要运输到适当的亚细胞位置进行翻译或包装；同样，新合成的Gag需要靶向到质膜上进行病毒组装。利用我们新开发的成像工具，我们将研究HIV-1 RNA在细胞质中运输的机制。HIV-1 RNA运输到质膜进行组装；我们将研究这种靶向事件的性质，包括在组装过程中单体RNA还是二聚体RNA被靶向，以及RNA在质膜附近停留的时间。我们还将研究Gag和RNA在极化T细胞和病毒突触中的靶向作用。这些实验将使我们了解目前知之甚少的HIV-1复制的各个方面，并使我们能够更好地了解HIV-1如何利用细胞机制来运输其大分子。【对应2011年10月HIV耐药项目实地考察报告中的胡项目3】

We have examined the complex interactions needed for generating an infectious virus. We showed that the mature capsid proteins from two different lentiviruses, HIV-1 and SIVmac, can assemble into the mature core of the infectious particle. Additionally, we quantified the amounts of functional nucleocapsid (NC) and p6 protein needed during HIV-1 infection, and determined the effects of treating HIV-1 with suboptimal concentrations of protease inhibitors on viral protein processing and RNA maturation. We will study the trafficking of HIV-1 macromolecules and assembly. Once exported from the nucleus, HIV-1 RNA needs to traffic to proper subcellular locations to be translated or packaged; similarly, the newly synthesized Gag needs to be targeted to the plasma membrane for virus assembly. Using our newly developed imaging tools, we will investigate the mechanisms used by HIV-1 RNA for transport in the cytoplasm. HIV-1 RNA traffics to the plasma membrane for assembly; we will investigate the properties of this targeting event, including whether monomeric or dimeric RNA is targeted during assembly and the dwell time of the RNA that stays near the plasma membrane. We will also investigate Gag and RNA targeting in polarized T cells and in viral synapses. These experiments will provide an understanding of aspects of HIV-1 replication that we currently know very little about and will allow us to better understand how HIV-1 uses the cellular machinery to traffic its macromolecules.[Corresponds to Hu Project 3 in the October 2011 site visit report of the HIV Drug Resistance Program]