Role of cell polarity regulators in HIV spreading

细胞极性调节剂在 HIV 传播中的作用

• 批准号: 10323026
• 负责人: HEINRICH GOTTLINGER
• 金额: $ 53.28万
• 依托单位: UNIV OF MASSACHUSETTS MED SCH WORCESTER
• 依托单位国家: 美国
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-01-01 至 2024-12-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10323026
• 关键词: Actins; Antigen-Presenting Cells; CD4 Positive T Lymphocytes; CDC42 gene; Cell Line; Cell Polarity; Cells; Complex; Cues; Cytoskeleton; Data; Drug Targeting; Eukaryotic Cell; Exocytosis; FMNL1 gene; Family; Filopodia; Golgi Apparatus; Guanosine Triphosphate Phosphohydrolases; HIV; HIV-1; Human; Infection; Investigation; Knock-out; Life Cycle Stages; Mediating; Membrane; Microtubule-Organizing Center; Microtubules; Modeling; Molecular; Monomeric GTP-Binding Proteins; PAK-1 kinase; PARD6A gene; Peripheral Blood Mononuclear Cell; Phosphotransferases; Polymerase; Process; Protein Kinase; Proteins; Public Health; Reporting; Role; Secretory Vesicles; Signal Pathway; Site; Surface; T-Lymphocyte; Vesicle; Viral; Virion; Virus; Yeasts; cdc42 GTP-Binding Protein; cytokine; experimental study; immunological synapse formation; insight; man; polarized cell; polymerization; reconstitution; response; synaptogenesis; trafficking; transmission process; virological synapse

ABSTRACT HIV-1-infected T cells can form stable conjugates with non-infected T cells in a process known as “virological synapse” formation. This process is reminiscent of the formation of an “immunological synapse”, during which CD4+ T cells rapidly polarize the actin cytoskeleton, the microtubule-organizing center (MTOC), and cytokine- containing vesicles towards antigen-presenting cells. The polarization of CD4+ T cells during immunological synapse formation depends on the RHO family GTPase CDC42, a molecular switch that has a key role in the establishment of polarity in eukaryotic cells. We have now observed that CDC42 is critical for the efficient spreading of HIV-1 in several T cell lines and in primary cells. However, our data also imply that CDC42 is dispensable for the completion of a single cycle of replication. Together, our observations implicate CDC42 in the cell-to-cell transmission of HIV-1. CDC42 stimulates the formation of membrane extensions, such as filopodia, through effectors that mediate the polarization of the actin cytoskeleton, and HIV-1 can exploit filopodial bridges to spread from cell to cell. Thus, our data let us to propose a working model in which CDC42 is crucial for the formation of intercellular extensions that facilitate the transfer of HIV-1 between CD4+ T cells. In support of this model, we have observed that CDC42 is required for the formation of HIV-1-induced membrane extensions by MOLT-3 cells. An alternative working model is that CDC42 is required for the polarized trafficking of HIV-1 virion components to the virologic synapse. We propose to directly examine the roles of CDC42 in HIV-1 cell-to-cell transmission and virological synapse formation, and to determine whether HIV-1 regulates the activity of CDC42. We also propose to examine the roles of CDC42 effectors that regulate localized actin assembly and polarized trafficking in HIV-1 spreading. Among these effectors are F-BAR proteins that connect to actin polymerization machinery, as does the F-BAR protein PACSIN2, which we have recently implicated in the cell-to-cell transmission of HIV-1. Notably, our preliminary results indicate that certain CDC42 effectors, including the CDC42-regulated actin polymerase FMNL1 and a putative CDC42 effector that controls polarized exocytosis, have crucial roles in HIV-1 replication. The proposed studies have the potential to yield fundamental new insights into the mechanism of an important but poorly understood mode of HIV-1 transmission. Of particular significance would be the identification of a kinase downstream of CDC42 as being critical for HIV-1 spreading, since protein kinases constitute one of the most important groups of drug targets.

抽象的 HIV-1感染的T细胞可以在称为“病毒学”的过程中与未感染的T细胞形成稳定的共轭物 突触”的形成。这个过程让人联想到“免疫突触”的形成，在此期间 CD4+ T细胞迅速使肌动蛋白细胞骨架，微管组织中心（MTOC）和细胞因子 - 含有蔬菜朝着抗原呈递细胞。免疫学期间CD4+ T细胞的极化 突触的形成取决于Rho家族GTPase CDC42，这是一种分子开关，在 在真核细胞中建立极性。 我们现在观察到CDC42对于在几个T细胞系中的有效扩散HIV-1至关重要 在原代细胞中。但是，我们的数据还暗示CDC42对于完成 复制周期。总之，我们的观察结果暗示了CDC42在HIV-1的细胞到细胞传递中。 Cdc42刺激膜扩展的形成，例如丝状菌，通过生效者的形成 介导肌动蛋白细胞骨架的极化，而HIV-1可以利用丝虫桥从细胞中扩散 到细胞。这，我们的数据使我们提出了一个工作模型，其中CDC42对于形成至关重要 促进HIV-1在CD4+ T细胞之间转移的细胞间延伸。为了支持该模型，我们 已经观察到Cdc42是由Molt-3形成HIV-1诱导的膜延伸所必需的 细胞。另一种工作模型是，HIV-1病毒的极化运输需要CDC42 病毒式突触的组成部分。 我们建议直接检查Cdc42在HIV-1细胞到细胞传播和病毒学中的作用 突触形成，并确定HIV-1是否调节CDC42的活性。我们还建议 检查调节局部肌动蛋白组装和两极分化在HIV-1中的CDC42生效子的作用 蔓延。其中包括与肌动蛋白聚合机械连接的F-BAR蛋白， F-BAR蛋白PACSIN2，我们最近在HIV-1的细胞到细胞传播中实施。 值得注意的是，我们的初步结果表明某些CDC42生效子，包括CDC42调节的肌动蛋白 聚合酶FMNL1和控制极化胞吐作用的假定CDC42效应子在 HIV-1复制。 拟议的研究有可能产生基本的新见解 重要但不了解HIV-1传输模式。特别重要的是 鉴定Cdc42下游的激酶对于HIV-1扩散至关重要，因为蛋白激酶 构成最重要的药物靶标组之一。