Dynamics of HIV Nuclear Interactions

摘要，项目2 感染细胞后，HIV将其RNA逆转录为病毒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、迁移到整合位点和选择整合位点是必不可少的，但人们对此知之甚少 艾滋病毒复制的步骤。深入了解病毒如何利用宿主因素来完成这些关键 需要复制步骤来确定有希望的分子靶点，以开发新的抗逆转录病毒药物。 治疗核输入后，完整的病毒核心被转运到称为核的染色质间结构域， 斑点，它们在那里脱膜，以便前整合复合物（PIC）可以将vDNA整合到附近的 染色质在目标1中，我们将确定和阐明动态的HIV核心-宿主细胞相互作用， 病毒核心的脱壳效率/动力学和核穿透距离;我们还将确定是否 HIV核心-宿主相互作用影响整合位点的全基因组选择， 实验方法。HIV整合的主要底物是染色质和核小体DNA， 整合酶（IN）与透镜上皮的结合有利于整合到转录活性基因中 衍生生长因子（LEDGF）。HIV PIC如何与LEDGF和核小体相互作用，以及哪些靶位点 有利于通过纯化的组装的IN-vDNA复合物（整合体）整合。在 目的二，构建生理学相关的染色质体外整合靶点，确定整合的优选区域 病毒整合到核小体底物，并阐明宿主因子和染色质状态如何调节 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， 直接将病毒DNA整合到染色质中。一般认为，整合位点的染色质状态 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， 活动性或潜伏性感染的控制建立仍然是个谜。艾滋病毒潜伏宿主重新引发感染 在停止抗逆转录病毒疗法后，它们迄今为止阻碍了治愈艾滋病毒感染的发展。我们 将开发多种实验方法来阐明建立潜伏感染的机制， 重新启动转录，这可能促进潜伏期重新激活或潜伏期促进治疗的发展 并实现根除或功能性治愈艾滋病毒感染。在目标3中，我们将开发多个实验 确定IN、达特和体内整合位点的作用的系统，以检查整合位点的作用 染色质在建立活动感染与潜伏感染中的作用。总的来说，这些研究将提供变革性的见解， 进入HIV脱壳，整合位点选择，指导整合进入核小体的分子机制， DNA，并阐明整合位点选择对HIV转录能力的功能后果 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.