The role of FEZ1 in early HIV-1 infection

FEZ1 在早期 HIV-1 感染中的作用

• 批准号: 10438790
• 负责人: Mojgan Hosseini Naghavi
• 金额: $ 36.02万
• 依托单位: NORTHWESTERN UNIVERSITY AT CHICAGO
• 依托单位国家: 美国
• 财政年份: 2012
• 资助国家: 美国
• 起止时间: 2012-09-24 至 2024-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10438790
• 关键词: Adaptor Signaling Protein; Affect; Affinity; Binding; Binding Proteins; C-terminal; Capsid; Cell Line; Cell Nucleus; Cells; Coiled-Coil Domain; Collaborations; Competitive Binding; Complex; Coupled; Cytoplasm; Data; Development; Dynein ATPase; Elongation Factor; Equilibrium; Event; Exhibits; Filament; Funding; HIV Infections; HIV-1; Human; Image; In Vitro; Individual; Infection; Integration Host Factors; Kinesin; Location; Longevity; Mediating; Microglia; Microtubule Stabilization; Microtubules; Modification; Motor; Nature; Nucleocapsid; Outcome; Phosphorylation; Phosphotransferases; Play; Plus End of the Microtubule; Process; Proteins; Public Health; Resource-limited setting; Reverse Transcription; Role; Suggestion; T-Lymphocyte; Testing; Universities; Viral; Viral Genome; Work; antiretroviral therapy; base; cell motility; cell type; cofactor; design; genetic regulatory protein; innovation; insight; mutant; novel strategies; overexpression; particle; preference; recruit

Although widespread use of combination antiretroviral therapy (cART) has effectively increased the life span of many infected individuals, HIV-1 continues to be a major public health issue in both developed and poor resource settings. As such, understanding the basic mechanisms of its replication cycle is instrumental to the development of new approaches to treat infection. HIV-1 employs unusual, intricately intertwined early infection strategies involving reverse transcription, disassembly of capsid core (also known as “uncoating”) and transport to the nucleus. Although its precise timing and location remain contentious, growing evidence suggests that at least partial uncoating occurs in the cytoplasm during transport to the nucleus. Indeed, incoming HIV-1 particles exhibit microtubule (MT) based bi-directional motility suggestive of their association with both inward (dynein) and outward (kinesin) MT motors, and recent studies suggest that the opposing forces generated by these motors facilitate uncoating. Despite this, HIV-1 does not appear to bind motors directly but instead, uses motor adaptors whose identity remained enigmatic until recent years. Our work funded in the previous cycle identified the HIV-1 kinesin-1 adaptor as Fasiculation and Elongation Factor Zeta 1 (FEZ1). We further established FEZ1’s central role in the transport and uncoating of incoming viral particles in natural target cells, which is regulated through FEZ1 phosphorylation that controls kinesin-1 activity. Moreover, we found that HIV-1 cores bind microtubule associated regulatory kinase 2 (MARK2) to locally control FEZ1 phosphorylation on viral particles. We further showed that HIV-1 particles also bind highly specialized MT regulatory proteins to induce the formation of stable MT networks, a subset of MT filaments favored by kinesin motors. Using innovative structural and functional studies in collaboration with the Xiong Lab at Yale University, our preliminary data reveals an usual and high affinity binding strategy used by HIV-1 to engage FEZ1 for transport that is mediated by capsid hexamers and one of four coiled-coil domains in FEZ1. Data also suggests that FEZ1 and MARK2 compete for binding in a manner that controls the extent of FEZ1 phosphorylation on HIV-1 capsids. In addition, we identify a new host factor that our data suggests binds distinct coiled-coil regions in FEZ1 and is exploited by incoming viral particles to enhance MT stabilization at the cell periphery. Cumulatively, our data suggests that distinct coiled-coil domains in FEZ1 mediate capsid binding, motor recruitment and MT stabilization to coordinate several aspects of early HIV-1 transport and uncoating. In this proposal, we aim to determine how FEZ1 and MARK2 function on the HIV-1 capsid to promote early infection and expand upon our new findings that FEZ1 plays a multifunctional role in early infection by recruiting both motors and regulators of MT stability to incoming HIV-1 particles. The outcome of our studies will provide important mechanistic insights into the multifunctionality of FEZ1 and expand our broader understanding of how HIV-1 controls several important steps in early infection of natural target cells.

尽管联合抗逆转录病毒疗法（cART）的广泛使用有效地延长了患者的寿命 许多感染者，HIV-1 仍然是发达国家和贫困国家的一个主要公共卫生问题 资源设置。因此，了解其复制周期的基本机制有助于 开发治疗感染的新方法。 HIV-1 采用不寻常的、错综复杂的早期感染 涉及逆转录、衣壳核心拆卸（也称为“脱壳”）和 运输至细胞核。尽管其精确的时间和地点仍然存在争议，但越来越多的证据表明 表明在运输到细胞核的过程中，细胞质中至少发生部分脱壳。的确， 传入的 HIV-1 颗粒表现出基于微管 (MT) 的双向运动，表明它们之间的关联 具有向内（动力蛋白）和向外（驱动蛋白）MT 马达，最近的研究表明相反的 这些电机产生的力有利于脱漆。尽管如此，HIV-1 似乎并没有结合电机 直接而是使用电机适配器，其身份直到最近几年仍然是个谜。我们的工作 上一周期资助的项目将 HIV-1 驱动蛋白-1 接头确定为肌颤动和伸长因子 Zeta 1（FEZ1）。我们进一步确定了 FEZ1 在传入病毒颗粒的运输和脱壳中的核心作用 在天然靶细胞中，它通过控制驱动蛋白-1 活性的 FEZ1 磷酸化进行调节。 此外，我们发现 HIV-1 核心局部结合微管相关调节激酶 2 (MARK2) 控制病毒颗粒上的 FEZ1 磷酸化。我们进一步表明 HIV-1 颗粒也高度结合 专门的 MT 调节蛋白诱导稳定 MT 网络（MT 丝的一个子集）的形成 受到驱动蛋白马达的青睐。与 Xiong 合作进行创新的结构和功能研究 在耶鲁大学实验室，我们的初步数据揭示了 HIV-1 使用的一种常见的高亲和力结合策略 使 FEZ1 参与由衣壳六聚体和 FEZ1 中四个卷曲螺旋结构域之一介导的运输。 数据还表明 FEZ1 和 MARK2 以控制 FEZ1 范围的方式竞争结合 HIV-1 衣壳上的磷酸化。此外，我们还发现了一个新的宿主因子，我们的数据表明该因子与它结合 FEZ1 中独特的卷曲螺旋区域，并被传入的病毒颗粒利用以增强 MT 的稳定性 细胞外围。总的来说，我们的数据表明 FEZ1 中不同的卷曲螺旋结构域介导衣壳 结合、运动募集和 MT 稳定，以协调早期 HIV-1 运输和 脱涂层。在本提案中，我们的目标是确定 FEZ1 和 MARK2 如何在 HIV-1 衣壳上发挥作用，以 促进早期感染并扩展我们的新发现，即 FEZ1 在早期感染中发挥多功能作用 通过招募 MT 稳定性的马达和调节器来应对传入的 HIV-1 颗粒的感染。结果 我们的研究将为 FEZ1 的多功能性提供重要的机制见解，并扩大我们的研究范围 更广泛地了解 HIV-1 如何控制自然靶细胞早期感染的几个重要步骤。