Gag Trafficking, Assembly, and Release

堵嘴贩运、组装和释放

• 批准号: 10702636
• 负责人: eric freed
• 金额: $ 82.37万
• 依托单位: DIVISION OF BASIC SCIENCES - NCI
• 依托单位国家: 美国
• 资助国家: 美国
• 起止时间: 至
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10702636
• 关键词: Binding; Binding Proteins; Biochemistry; Capsid Proteins; Cell membrane; Cell surface; Cells; Cellular biology; Collaborations; Complex; Destinations; Development; Family; Glycoproteins; Goals; HIV; HIV-1; HIV-2; Imaging Techniques; Immunoglobulins; Inositol; Integration Host Factors; Interferons; Membrane; Molecular; Mucins; Natural Immunity; Ohio; P-selectin ligand protein; Pathway interactions; Phosphatidylinositols; Phosphatidylserines; Play; Production; Protein Family; Proteins; Reporting; Research; Role; SIV; Site; Sphingomyelinase; T-Lymphocyte; Universities; Viral; Virion; Virus; Virus Assembly; Work; antiretroviral therapy; env Gene Products; gene product; inhibitor; insight; interest; nef Protein; novel; particle; polyanion; protein function; trafficking; virology; vpu Protein

While it is clear that HIV-1 assembly occurs predominantly on the plasma membrane (PM), the itinerary that the HIV-1 Gag precursor follows to reach this destination remains ill defined. Likewise, the host cell machinery that promotes Gag trafficking to the PM is incompletely understood. We and others have demonstrated that the matrix (MA) domain of Gag regulates targeting to the site of virus assembly, and we discovered that the phosphoinositide PI(4,5)P2 is a key player in directing Gag to the PM. We hypothesize that host factors in addition to PI(4,5)P2 play a vital role in the trafficking of Gag to the PM. In this project, we are defining the role of host cell machinery in Gag trafficking to the PM and in subsequent steps of particle assembly and release. This effort combines virology, biochemistry, cell biology, and imaging techniques. Our overarching goal is to establish a unified view of the mechanism and pathway(s) involved in the late stages of the HIV-1 replication cycle and to develop inhibitors of HIV-1 Gag trafficking, assembly, and release. ___ Most of our efforts, and those of our colleagues, with regard to late-acting host factors have focused on factors that promote HIV-1 particle assembly and release. However, we have become increasingly interested in cellular factors that interfere with the late stages of HIV-1 replication. The best-characterized example of a late-acting negative factor is tetherin (BST-2), an interferon-stimulated gene product that restricts viral particle release at the cell surface. Tetherin is counteracted by the HIV-1 Vpu protein and the Nef or Env proteins of certain strains of HIV-2 and simian immunodeficiency virus. Apart from tetherin, however, little is known about the host cell factors that interfere with HIV 1 assembly or release. We are engaged in studying these host proteins, with an initial focus on the T-cell immunoglobulin and mucin domain (TIM) family of phosphatidylserine-binding proteins. We recently reported, in collaboration with Dr. Shan-Lu Liu's lab (Ohio State University), that the TIM-family proteins strongly inhibit HIV-1 release by retaining HIV-1 particles on the cell surface through binding to phosphatidylserine on the viral membrane. We will further characterize the mechanism of action by which such host factors restrict HIV-1 particle production, resulting in diminished viral production and replication. We have been involved with studies examining the effect of the host factor PSGL-1 on the binding of virus particles to target cells and the incorporation of viral envelope glycoproteins into virions. We are also examining the role of neutral sphingomyelinase 2 on HIV assembly, release, and maturation. Finally, we have several major projects focused on the role of the small cellular polyanion inositol hexkisphosphate (IP6) in HIV-1 assembly and maturation.

虽然很明显HIV-1的组装主要发生在质膜（PM）上， HIV-1 Gag前体到达这个目的地的路线仍然是病态的， 定义了同样，促进Gag向PM运输的宿主细胞机制是 不完全理解。我们和其他人已经证明，Gag的矩阵（MA）域 调节靶向病毒装配位点，我们发现磷酸肌醇 PI（4，5）P2是将Gag导向PM的关键角色。我们假设宿主因素 除了PI（4，5）P2之外，它们在Gag向PM的贩运中起着至关重要的作用。在本项目中， 我们正在定义宿主细胞机制在将Gag贩运到PM以及随后的 颗粒组装和释放的步骤。这项工作结合了病毒学、生物化学、细胞 生物学和成像技术。我们的首要目标是建立一个统一的观点， 参与HIV-1复制周期晚期阶段的机制和途径， 开发HIV-1 Gag运输、组装和释放的抑制剂。_我们的大部分努力， 以及我们的同事们，关于迟发宿主因素， 促进HIV-1粒子的组装和释放。然而，我们越来越多地 对干扰HIV-1复制晚期的细胞因子感兴趣。的 最典型的晚期作用负因子的例子是拴系蛋白（BST-2）， 干扰素刺激的基因产物，其限制病毒颗粒在细胞表面释放。 Tetherin被HIV-1 Vpu蛋白和某些人的Nef或Env蛋白抵消。 HIV-2和猿免疫缺陷病毒株。然而，除了拴系蛋白， 已知的宿主细胞因子干扰HIV 1的组装或释放。我们 从事研究这些宿主蛋白质，最初的重点是T细胞免疫球蛋白 和磷脂酰丝氨酸结合蛋白的粘蛋白结构域（TIM）家族。我们最近报道，在 与刘山璐博士的实验室（俄亥俄州州立大学）合作，TIM家族蛋白 通过将HIV-1颗粒保留在细胞表面， 与病毒膜上的磷脂酰丝氨酸结合。我们将进一步描述 这些宿主因子限制HIV-1颗粒产生的作用机制， 减少病毒的生产和复制。我们参与了一些研究， 宿主因子PSGL-1对病毒颗粒与靶细胞结合的影响， 病毒包膜糖蛋白掺入病毒体。我们也在研究 中性鞘磷脂酶2对HIV装配、释放和成熟的影响。最后，我们有几个 主要项目集中在小细胞聚阴离子肌醇六磷酸的作用 (IP6)HIV-1的组装和成熟。