The Role of Nef and Cyclophilin A in HIV-1 Disassembly

描述(由申请人提供)：新的HIV-1抗病毒药物的开发取决于我们对病毒复制过程中各个步骤的理解。也许对HIV-1复制最不了解的方面是分解过程。我们的初步数据表明，病毒蛋白Nef和细胞因子亲环素A(CyPA)参与了拆解的某些方面。我们已经证明，具有自身nef缺失并被HIV-2或SIV Nef“反式”替换的HIV-1病毒对环孢素A治疗产生抗药性。这表明Nef和CyPA之间存在某种相互依赖关系。已有研究表明Nef和CyPA可以直接相互作用。我们已经在自己的实验室中使用Far Western blots和SELDI质谱学证实了这一结果。我们考虑Nef和CyPA之间的相互作用以及它们与病毒核心中的CA的潜在相互作用是否对复制重要。我们的假设是：Nef、CyPA和CA之间的相互作用对于增强病毒的感染性是重要的。我们的方法总结为三个特定的目的：1.用多轮感染力试验鉴定HIV-2和SIV Nef诱导HIV-1病毒颗粒中亲环素A独立的能力。2.确定HIV-1Nef和CyPA之间的相互作用是否与传染性的增强有关。3.确定HIV-1、HIV-2或SIV Nef蛋白是否能直接或间接与CA蛋白结合。更好地了解Nef和CyPA之间的关系将为这一复制过程中特征不佳的步骤提供关键细节，这可能为抗病毒治疗提供一个有吸引力的新靶点。

DESCRIPTION (provided by applicant): The development of new HIV-1 antivirals is dependent on our understanding of the individual steps in viral replication. Perhaps the least understood aspect of HIV-1 replication is the process of disassembly. Our preliminary data suggest that the viral protein Nef and the cellular factor cyclophilin A (CyPA) are involved in some aspect of disassembly. We have shown that HIV-1 viruses that have their own nef deleted and replaced by HIV-2 or SIV Nef "in trans" become resistant to cyclosporine A treatment. This suggests some interdependence between Nef and CyPA. It has been previously shown that Nef and CyPA can directly interact. We have confirmed this result in our own lab using Far Western blots and SELDI mass spectrometry. We consider whether the interactions between Nef and CyPA and their potential interactions with CA in the viral core are important for replication. Our hypothesis is: that interaction between Nef, CyPA and CA are important for enhancement of viral infectivity. Our approach is summarized in three specific aims: 1. Characterize the ability of HIV-2 and SIV Nef to induce cyclophilin A independence in HIV-1 virions using a multi-round infectivity assay. 2. Determine if the interaction between HIV-1 Nef and CyPA is relevant to enhancement of infectivity. 3. Determine if the HIV-1, HIV-2 or SIV Nef proteins can directly or indirectly bind to CA protein. A better understanding of the relationship between Nef and CyPA will provide critical details about this poorly characterized step in replication, which could provide an attractive new target for antiviral therapy.