Dynamics of HIV Nuclear Interactions

摘要，项目2 在感染细胞后，HIV将其RNA逆转录成病毒DNA(VDNA)，并整合到宿主细胞中 基因组。VDNA必须进入细胞核才能进入宿主DNA进行整合，但VDNA如何获得 核进入、向整合地点的迁移以及选择整合地点是必不可少的，但人们对此知之甚少 艾滋病毒复制的步骤。彻底了解病毒如何利用宿主因素来完成这些密钥 需要复制的步骤来确定开发新的抗逆转录病毒的有希望的分子靶点 治疗。在核进口之后，完整的病毒核心被运输到称为核的染色质间域 斑点，在那里他们解开涂层，以便前整合复合体(PIC)可以将VDNA整合到附近 染色质。在目标1中，我们将识别和阐明影响核的艾滋病毒核心-宿主细胞的动态相互作用 去涂层效率/动力学和病毒核心的核穿透距离；我们还将确定 HIV核心-宿主相互作用通过多重协同作用影响全基因组整合位点的选择 实验方法。HIV整合的主要底物是染色质和核小体DNA，以及 整合酶(IN)与晶状体上皮细胞结合有利于转录活性基因的整合 衍生生长因子(LEDGF)。HIV PIC如何与LEDGF和核小体相互作用，以及哪些靶点是 被纯化的组装的IN-VDNA复合体(内含体)整合的可能性尚未确定。在……里面 目的2，我们将在体外构建与生理相关的染色质整合靶点，确定优先区域 用于病毒整合到核小体底物，并阐明宿主因素和染色质状态是如何调节的 集成站点首选项。这些方向将阐明病毒/宿主相互作用的机制基础 病毒DNA直接整合到染色质中。一般认为，整合部位的染色质状态 决定转录活性或进展到潜伏期。然而，宿主染色质状态和病毒因子 控制主动或潜伏感染的建立仍然是个谜。随着艾滋病毒潜伏宿主重新引发感染 在停止抗逆转录病毒治疗后，到目前为止，他们阻止了艾滋病毒感染治疗方法的开发。我们 将开发多种实验方法来阐明建立潜伏感染和 重新启动转录，这可能会促进潜伏期重新激活或潜伏期促进治疗的发展 并实现根除或治愈艾滋病毒感染的有效方法。在目标3中，我们将开发多个实验 确定IN、TAT和体内整合部位作用的系统，以检查整合部位的作用 染色质在建立主动感染与潜伏感染中的作用。总体而言，这些研究将提供变革性的见解 进入HIV脱壳，整合位点选择，引导整合到核小体的分子机制 DNA，并阐明整合位点选择对HIV转录能力的功能影响 和延迟。

ABSTRACT, PROJECT 2 After infecting a cell, HIV reverse transcribes its RNA into viral DNA (vDNA) that integrates into the host cell genome. The vDNA must enter the nucleus to access the host DNA for integration, but how the vDNA gains nuclear entry, migrates to sites of integration, and selects sites of integration are essential yet poorly understood steps in HIV replication. A thorough understanding of how the virus exploits host factors to complete these key steps in replication is needed to identify promising molecular targets for development of new antiretroviral therapies. Following nuclear import, intact viral cores are transported to interchromatin domains called nuclear speckles where they uncoat so that the preintegration complex (PIC) can integrate the vDNA into nearby chromatin. In Aim 1, we will identify and elucidate dynamic HIV core-host cell interactions that influence nuclear uncoating efficiency/kinetics and the nuclear penetration distance of viral cores; we will also determine whether the HIV core-host interactions affect genome-wide selection of integration sites using multiple synergistic experimental approaches. The main substrate for HIV integration is chromatin and nucleosomal DNA, and integration into transcriptionally active genes is favored by association of integrase (IN) with lens epithelium derived growth factor (LEDGF). How HIV PICs interact with LEDGF and nucleosomes and which target sites are favored for integration by purified assembled IN-vDNA complexes (intasomes) has not yet been determined. In Aim 2, we will construct physiologically relevant chromatin targets of integration in vitro, define preferred regions for viral integration into nucleosome substrates and elucidate how host factors and chromatin states modulate integration site preferences. These directions will elucidate the mechanistic bases by which viral/host interactions direct viral DNA integration into chromatin. It is generally thought that the chromatin state at integration sites determines transcriptional activity or progression to latency. However, host chromatin states and viral factors that control establishment of active or latent infection remain enigmatic. As HIV latent reservoirs reinitiate infection upon cessation of antiretroviral therapy, they have thus far prevented development of a cure for HIV infection. We will develop multiple experimental approaches to elucidate mechanisms that establish latent infection and reinitiate transcription, which may promote development of latency-reactivating or latency promoting treatments and achieve eradication or a functional cure for HIV infection. In Aim 3, We will develop multiple experimental systems to determine the roles of IN, Tat and in vivo integration sites to examine the role of the integration site chromatin in establishment of active vs. latent infection. Overall, these studies will provide transformative insights into HIV uncoating, integration site selection, the molecular machinery that directs integration into nucleosomal DNA, and elucidate the functional consequences of integration site selection on HIV transcriptional competency and latency.