Interpreting a hard-won structure of the arenavirus prefusion glycoprotein

 描述(申请人提供)：ArenaVirus家族包括50种已知病毒，包括严重的人类病原体和实验室模型，如淋巴细胞性脉络膜脑膜炎病毒(LCMV)。所有的东半球阿拉伯病毒和一些新世界的阿拉伯病毒都使用α-肌营养不良聚糖作为细胞受体。这种分子与病毒表面表达的单一糖蛋白结合，称为GP。因此，GP介导附着、融合和进入宿主细胞，也决定了嗜性和通常的致病性。了解糖蛋白的结构，特别是存在于病毒表面的寡聚体、融合糖蛋白的结构，对于了解病毒的入侵和趋向性以及开发疫苗、抗体和抗病毒药物是至关重要的。然而，目前还不存在任何禽流感病毒的任何灌流GP的结构。此外，目前还不存在任何使用α-营养不良聚糖作为受体的ArenaVirus的GP的GP1受体结合亚单位的结构。在我们的初步数据中，我们描述了我们新确定的、来之不易的来自α营养不良多糖结合的旧世界病毒LCMV的完全糖基化、融合前病毒GP的晶体结构。这种LCMV GP胞外结构域在晶体中形成一个三聚体。在目标1中，我们建议确定这种排列是否代表ArenaVirus表面的生物相关三聚体。在目标2中，我们建议定位旧世界ArenaVirus GP的α-营养不良糖结合位点。R21旨在用于新的研究，这些研究开拓了新的领域，并在新的方向上扩展了先前的结果。这里提出的研究确实将为理解这一非常大的人类病原体家族的组装和进入提供变革性的模型。它还将为疫苗、疗法和免疫治疗鸡尾酒的设计提供新的模板。AIM1将提供第一个生物支持的预融合模型-寡聚体GP，该模型可能适用于整个ArenaVirus家族。AIM 2将阐明许多旧世界阿拉伯病毒和C新世界分支病毒的受体结合部位。AIM 2还将为理解病毒的趋向性提供模板，并将解释决定疾病进程的历史突变，这些突变已被广泛用于阐明病毒的免疫生物学。

 DESCRIPTION (provided by applicant): The arenavirus family includes >50 known viruses, including both severe human pathogens and laboratory models such as lymphocytic choriomeningitis virus (LCMV). All of the Old World arenaviruses and some of the New World arenaviruses use alpha- dystroglycan as a cellular receptor. This molecule is bound by the single glycoprotein expressed on the viral surface, termed GP. GP thus mediates attachment, fusion and entry into host cells, and also determines tropism and often, pathogenicity. Understanding the structure of GP, especially the structure of oligomeric, prefusion GP as it exists on the viral surface, is essential to understanding virus entry and tropism and to developing vaccines, antibodies, and antivirals. However, no structure yet exists for any prefusion GP of any arenavirus. Further, no structure yet exists for the GP1 receptor-binding subunit of GP for any arenavirus that uses alpha-dystroglycan as a receptor. In our preliminary data, we describe our newly determined, hard-won crystal structure of the fully glycosylated, prefusion arenavirus GP from the α-dystroglycan- binding Old World virus LCMV. This LCMV GP ectodomain forms a trimer in the crystals. In Aim 1, we propose to determine if this arrangement represents the biologically relevant trimer on the surface of arenaviruses. In Aim 2, we propose to map the α- dystroglycan-binding site of the Old World arenavirus GP. An R21 is intended for novel studies that break new ground and extend previous results in new directions. The research proposed here will indeed provide transformative models for understanding assembly and entry of this very large family of human pathogens. It will also provide new templates for design of vaccines, therapeutics, and immunotherapeutic cocktails. Aim1 will provide the first biologically supported model of prefusion, oligomeric GP, which is likely applicable to the entire arenavirus family. Aim 2 will elucidate the receptor-binding site for the many Old World arenaviruses and those of clade C New World arenaviruses as well. Aim 2 will also provide templates for understanding viral tropism, and will explain historical mutations that determine disease course and that have been used extensively to illuminate virus immunobiology.