HIV-1 Preintegration Trafficking and Nuclear Localization

描述（由申请人提供）：HIV-1细胞的感染经过一系列步骤，每一个步骤都定义了抗病毒药物干预的潜在靶点。目前的药物靶向由蛋白酶、逆转录酶和整合酶催化的关键病毒活性，但耐药性的出现要求不断开发具有新作用模式的新药。HIV-1在复制时依赖于与许多细胞蛋白的相互作用，而maraviroc是一种破坏病毒包膜糖蛋白与细胞表面CCR5受体之间相互作用的药物，是一种被批准的病毒-细胞相互作用抑制剂，可以阻止病毒进入细胞。HIV-1复制蛋白的另一个关键因素是整合前复合物中间体（整合酶和反向转录物的载体）进入细胞核内染色体的能力，在细胞核内进行病毒DNA整合。像HIV-1这样的慢病毒使用一种能量依赖的过程通过双相核包膜的核孔复合物来运输它们的预整合复合物，尽管HIV-1核运输的分子机制尚不清楚。这项更新资助申请支持的工作确定了许多细胞蛋白是HIV-1复制的潜在关键辅助因子，其中包括运输蛋白-3，

DESCRIPTION (provided by applicant): Infection of a cell by HIV-1 proceeds through a series of steps, each of which defines a potential target for antiviral drug intervention. Current drugs target key viral activities catalyzed by the protease, reverse transcriptase, and integrase enzymes, but emergence of drug resistance calls for continual development of new drugs with novel modes of action. HIV-1 depends on interactions with numerous cellular proteins as it replicates and maraviroc, a drug that disrupts the interaction between the viral envelope glycoprotein and cellular surface CCR5 receptor, is an approved inhibitor of a virus-cell interaction that blocks the ability of the virus to enter the cell. Also crucial to HIV-1 replicatin is the ability for the preintegration complex intermediate that houses the integrase and reverse transcript to access the chromosomes inside the cell nucleus, where viral DNA integration takes place. Lentiviruses like HIV-1 use an energy-dependent process to transport their preintegration complexes through nuclear pore complexes that riddle the biphasic nuclear envelope, though the molecular mechanisms underlying HIV-1 nuclear transport are poorly understood. Work supported by this renewal grant application identified numerous cellular proteins as potential critical cofactors of HIV-1 replication and a significant number of these, including transportin-3, nucleoporin 153, and nucleoporin 358 were accordingly implicated in preintegration complex nuclear import due to their known functions within the cell. Subsequent work indeed confirmed this contention, though it remains unclear how these and other cellular and viral proteins precisely dictate HIV-1 preintegration complex nuclear import. Using numerous virology, biochemical, and genetic approaches, the work proposed herein will determine the mechanisms of HIV-1 nuclear import, focusing on novel protein interactions between the virus and host cellular components that are essential for the process. Such discoveries will define new targets for the development of inhibitors that block critical HIV-host interactions, which would be expected to increase the breadth of future antiviral armaments in the ongoing battle to control the spread of HIV/AIDS. PUBLIC HEALTH RELEVANCE: Despite HAART successes, drug resistance emerges due to the inherent viral genetic barrier required to build resistance to any given compound plus associated toxicity of compound use, which significantly affects patient compliance. These observations highlight the ongoing need to develop new antiviral inhibitors, and crucial interactions between HIV-1 and cellular cofactors have been highlighted in recent years as novel drug targets. This proposal will uncover novel details of how the HIV-1 preintegration complex, a critical viral replication intermediate, accesses the cellular nucleus where viral integration occurs, which will define novel targets for antiviral drug development moving forward.