Dissecting the Conformational Flexibility of HIV-1 Envelope Glycoproteins

剖析 HIV-1 包膜糖蛋白的构象灵活性

• 批准号: 10546775
• 负责人: Alon Herschhorn
• 金额: $ 60.62万
• 依托单位: UNIVERSITY OF MINNESOTA
• 依托单位国家: 美国
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-06-15 至 2027-05-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10546775
• 关键词: Adopted; Affect; Amino Acids; Antibodies; Antigens; Archives; Binding; Binding Sites; Biology; Cells; Complex; Cryoelectron Microscopy; Development; Electrons; Elements; Epitopes; Evolution; Generations; Glycoproteins; Goals; HIV; HIV Envelope Protein gp120; HIV Infections; HIV-1; HIV-1 vaccine; Heterogeneity; Kinetics; Knowledge; Maps; Measures; Mediating; Modeling; Molecular; Molecular Conformation; Mutation; Pathway interactions; Patients; Persons; Preventive vaccine; Publishing; Resolution; Shapes; Source; Spectrum Analysis; Structure; Testing; Therapeutic Intervention; Time; Translating; V3 Loop; Vaccine Design; Vaccines; Variant; Viral; Virus; Work; base; design; flexibility; improved; in vivo; insight; latent HIV reservoir; neutralizing antibody; pandemic disease; preventive intervention; resistant strain; single-molecule FRET; targeted treatment; therapeutic development; transmission process

ABSTRACT HIV-1 envelope glycoproteins (Envs) mediate viral entry into host cells and are the sole target of neutralizing antibodies. HIV-1 Envs of most primary HIV-1 strains typically exist in a closed conformation (State 1) and occasionally transit to downstream, more open conformations (State 2 and State 3). Thus, current knowledge guides immunogen design towards mimicking the Env closed conformation as the preferred target for eliciting broadly neutralizing antibodies (bnAbs) to block HIV-1 entry. However, Env preferred conformations of more than 37 million different circulating HIV-1 strains are unlikely to adopt exactly the same closed conformation. And we still do not know how different State 1 conformations of diverse natural HIV-1 variants are. Our hypothesis: State 1 Envs form a heterogenous group of Envs that exist in similar but not identical conformations. Accordingly, improved ability of bnAbs to recognize multiple Env conformations will broaden their neutralization activity. To test our hypothesis, we will assess the conformational heterogeneity of Envs from different strains and build mechanistic models for 1) Envs transitions, 2) generation and transmission of Envs that exist in specific conformations, and 3) broad recognition of different Env states. In Specific Aim 1 we will study the conformational diversity of transmitted/founder (T/F) HIV-1 strains, which can establish HIV-1 in vivo and are the only target of a preventive vaccine. We will study the mechanisms by which T/F Envs expose internal elements and how they transit to downstream conformations. In Specific Aim 2 we will investigate the generation and evolution of incompletely closed Env conformation. We will reconstruct the evolution pathway of T/Fs in patients by using available viral sequences to build evolved viruses at different time point followed by investigating changes in their conformational states over time. In parallel, we will study Env conformational diversity among HIV-1 strains that are archived in the latent HIV-1 reservoir of people living with HIV-1 and identify potential targets for therapeutic interventions. These approaches will allow us to build a mechanistic model for how incompletely closed Envs are generated, evolved, and transmitted. In Specific Aim 3 we will define important parameters for broad recognition of CD4-binding site (CD4-bs) on different Env conformations of diverse primary strains. We will study how the exceptionally broad N6 (CD4-bs) bnAb recognizes different Env conformations, will identify critical interactions with residues on open and closed Env conformations, and will solve cryo-EM structures of HIV-1 Envs in complex with N6 to define the mechanism of broad recognition. Overall, our study will provide high-resolution and comprehensive view on the biology of HIV-1 entry pathway, will refine the knowledge on HIV-1 Env conformations, and will form a strong basis for the development of new strategies for HIV-1 cure and vaccine design.

抽象的 HIV-1包膜糖蛋白（INVS）介导病毒进入宿主细胞，是中和的唯一目标 抗体。大多数主要HIV-1菌株的HIV-1 ENV通常存在于封闭构象中（状态1）和 有时转移到下游，更开放的构型（州2和状态3）。因此，当前的知识 指导免疫原设计用于模仿Env封闭构象作为引发的首选目标 广泛中和抗体（BNABS）以阻止HIV-1进入。但是，Env更喜欢更多的构象 超过3700万不同的循环HIV-1菌株不太可能采用完全相同的封闭构象。和 我们仍然不知道各种自然HIV-1变体的1构象如何。 我们的假设：状态1 Envs形成了一个异体群体，它们存在于相似但不完全相同 构象。因此，BNABS识别多个ENV构象的能力将提高能力 扩大他们的中和活性。 为了检验我们的假设，我们将评估来自不同菌株的ENV的构象异质性并建立 1）Envs的机械模型，2）特定于特定的ENV的生成和传播 构象和3）对不同的环境国家的广泛认识。在特定目标1中，我们将研究构象 传播/创建者（T/F）HIV-1菌株的多样性，可以在体内建立HIV-1，并且是唯一的目标 预防性疫苗。我们将研究t/f设想的机制，以及它们如何公开内部元素以及它们如何 过渡到下游构象。在特定目的2中，我们将研究的产生和演变 不完全封闭的env构象。我们将通过使用患者中T/FS的演变途径 可用的病毒序列在不同的时间点构建进化的病毒，然后研究变化 随着时间的流逝，它们的构象状态。同时，我们将研究HIV-1菌株之间的ENV构象多样性 存档在患有HIV-1的人的潜在HIV-1水库中，并确定了潜在的目标 治疗干预措施。这些方法将使我们能够建立一个机械模型 封闭的Envs是生成，进化和传播的。在特定目标3中，我们将定义重要参数 对不同原发性菌株的不同ENV构象的CD4结合位点（CD4-BS）的广泛认识。我们 将研究异常广泛的N6（CD4-BS）BNAB如何识别不同的ENV构象，将确定 与开放和封闭的Env构象中残留物的关键相互作用，并将解决的冷冻EM结构 HIV-1与N6复杂地设想，以定义广泛识别的机制。 总体而言，我们的研究将为HIV-1进入途径的生物学提供高分辨率和全面的看法， 将完善有关HIV-1 Env构象的知识，并将为开发新的知识构成强大的基础 HIV-1治疗和疫苗设计的策略。