Inositol Polyphosphates and HIV-1 Maturation

肌醇多磷酸盐和 HIV-1 成熟

• 批准号: 9927308
• 负责人: Christopher R Aiken
• 金额: $ 25.5万
• 依托单位: VANDERBILT UNIVERSITY MEDICAL CENTER
• 依托单位国家: 美国
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-02-25 至 2022-01-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9927308
• 关键词: Acquired Immunodeficiency Syndrome; Alpha Particles; Antiviral Agents; Binding; Binding Proteins; Biological Assay; Capsid; Cells; Cleaved cell; Complex; Cone; Dependence; Development; Dissociation; Drug Targeting; Drug resistance; Engineering; Enzymes; Foundations; HIV; HIV-1; In Vitro; Infection; Inositol; Laboratories; Lead; Ligands; Methods; Modeling; Molecular; Morphology; Mutation; Peptide Hydrolases; Persons; Pharmaceutical Preparations; Pharmacotherapy; Phytic Acid; Polyphosphates; Process; Production; Property; Proteins; Recombinant Proteins; Replication-Associated Process; Research; Retroviridae; Role; SP1 gene; Site; Structural Protein; Structure; Testing; Therapeutic; Viral; Virion; Virus Replication; base; drug development; gag Gene Products; gel electrophoresis; improved; mutant; novel; novel virus; particle; predictive modeling; self assembly; stoichiometry; virus host interaction

Project Summary/Abstract Replication of HIV-1, the causative agent of Acquired Immune Deficiency Syndrome (AIDS), involves the assembly of immature particles composed of the Gag polyprotein and subsequent maturation of these particles by proteolytic cleavage. Although HIV-1 infection can be effectively controlled through the judicious administration of antiviral drugs, therapy is not curative, and drug resistance is a constant concern. Axiomatically, HIV-1 depends on interactions with host cell molecules at every stage of its replication cycle. Although many of these virus-host interactions occur between proteins, the host cell metabolite inositol hexakisphosphate (IP6) has recently emerged as a key host molecule involved in HIV-1 replication. IP6 appears to bind to the Gag polyprotein in infected cells, thus stabilizing the Gag hexameric lattice and promoting virion assembly. Remarkably, IP6 also binds to the cleaved viral CA protein in vitro and promotes CA self-assembly into cone- like structures that are morphologically similar to native HIV-1 capsids. Based on these observations, a model has been proposed in which IP6 is released upon cleavage of the Gag lattice by the viral protease during HIV-1 maturation. Release of IP6 permits its binding to assembling CA hexamers, thus stabilizing the mature capsid lattice. In this project, we will validate key predictions of this model. Employing novel and sensitive assays to quantify the levels of IP5 and IP6 associated with purified subviral complexes, we will identify the specific cleavages in the Gag polyprotein required for dissociation of these ligands from the immature Gag lattice. Second, we will identify the molecular determinants of IP6 binding to the mature capsid lattice, including testing the role of Arg18 in CA that has been shown to form ionic interactions with IP6 in vitro. Finally, we will quantify the levels of IP6 present in particles of diverse retroviruses as a first step in understanding the range of retroviruses that utilize IP6 in their replication cycles. IP6 is the first non-nucleotide host cell metabolite on which HIV-1 replication has been shown to depend. Defining the mechanism of IP6 action in HIV-1 maturation is essential to understand how HIV-1 exploits this novel virus-host interaction. Ultimately, the project may lead to the development of new antiviral drugs, thus expanding the available therapeutic options for the long-term management of HIV-1 infection.

项目摘要/摘要 HIV-1的复制是获得免疫缺陷综合征（AIDS）的病因，涉及 由GAG多蛋白组成的未成熟颗粒的组装和随后的这些颗粒的成熟 通过蛋白水解裂解。尽管可以通过明智地控制HIV-1感染 抗病毒药物的给药，治疗无法治愈，耐药性一直是一个持续关注的问题。公理， HIV-1取决于在复制周期的每个阶段与宿主细胞分子的相互作用。虽然很多 这些病毒宿主相互作用发生在蛋白质之间，宿主细胞代谢物肌醇六磷酸（IP6）之间发生 最近出现了参与HIV-1复制的关键宿主分子。 IP6似乎绑定到插科打g 感染细胞中的多蛋白，从而稳定了GAG六聚体晶格并促进病毒体组装。 值得注意的是，IP6在体外还与切割的病毒CA蛋白结合，并促进CA自组装成锥体 就像形态学上与天然HIV-1衣壳相似的结构。基于这些观察，模型 已经提出了在HIV-1期间病毒蛋白酶在裂解GAG晶格后释放IP6 成熟。 IP6的释放允许其与组装Ca六聚体的结合，从而稳定成熟的衣壳 格子。在此项目中，我们将验证该模型的关键预测。采用小说和敏感的测定 量化与纯化的次病络合物相关的IP5和IP6的水平，我们将确定特定的 这些配体从未成熟的GAG晶格中解离所需的GAG多蛋白的分裂。 其次，我们将确定IP6与成熟的衣壳晶格结合的分子决定因素，包括测试 ARG18在CA中的作用已显示在体​​外与IP6形成离子相互作用。最后，我们将量化 不同逆转录病毒颗粒中存在的IP6水平是理解范围的第一步 在复制周期中利用IP6的逆转录病毒。 IP6是第一个非核苷酸宿主细胞代谢物 HIV-1的复制已被证明取决于。在HIV-1成熟中定义IP6动作的机制是 了解HIV-1如何利用这种新型病毒宿主相互作用。最终，该项目可能导致 新抗病毒药物的开发，从而扩大了长期可用的治疗选择 HIV-1感染的管理。