Dynamics and mechanisms of filovirus envelop glycoproteins

摘要 埃博拉疫情爆发的频率和严重性越来越高，需要扩大治疗和 预防措施。要满足这种未得到满足的需求，就需要更深入地了解分子。 丝状病毒复制的潜在机制。特别是，在丝状病毒包膜期间发生的动态事件 几十年来，糖蛋白(GP)介导的膜融合在进入细胞过程中一直没有得到阐明。 以前的研究已经确定了糖蛋白的蛋白水解性切割、受体结合以及糖蛋白的化学环境。 晚期内体是至关重要的。但这些事件和变量促进的分子机制 GP介导的膜融合尚不清楚。因此，一个完整而特定的丝状病毒融合模型， 它综合了宿主因素、环境条件和GP的构象变化，目前还不存在。 因此，丝状病毒的进入仍然是抑制剂未利用的目标。我们的长期目标是开发一种 糖蛋白介导膜融合的完整机制模型。我们最近的出版物，其中我们 证明单分子荧光方法在阐明构象动力学方面的能力 病毒粒子表面的EBOV GP，展示了我们为此目的所做的初步努力。在这里，我们的目标是在此基础上 成功地提出了一项涉及病毒学、细胞、结构和生物物理的多学科研究 阐明多丝状病毒GP的动力学和机制的方法学。我们将描述 构象变化、寄主因素和环境变量促进丝状病毒的机制 膜融合和进入细胞。拟议研究的完成将提供对以下方面的机械见解 丝状病毒的进入以及可以用新的治疗方法和免疫原来利用的病毒和宿主靶标。

SUMMARY The increasing frequency and severity of Ebola outbreaks demands an expanded repertoire of treatments and preventative measures. Answering this unmet need will require a deeper understanding of the molecular mechanisms underlying filovirus replication. In particular, the dynamic events that occur during filovirus envelope glycoprotein (GP)-mediated membrane fusion during entry into cells have evaded elucidation for decades. Previous studies have identified proteolytic cleavage of GP, receptor binding, and the chemical environment of the late endosome as being critical. But the molecular mechanisms by which these events and variables promote GP-mediated membrane fusion are not known. As a result, a complete and specific model of filovirus fusion, which integrates host factors, environmental conditions, and GP conformational changes currently does not exist. Therefore, filovirus entry continues to be an unutilized target for inhibitors. Our long-term goal is to develop a complete mechanistic model of GP-mediated membrane fusion. Our recent publications, in which we demonstrate the power of single-molecule fluorescence methods in elucidating the conformational dynamics of EBOV GP on the surface of virions, demonstrate our initial efforts toward this end. Here we aim to build on this success by proposing a multidisciplinary study involving virological, cellular, structural, and biophysical methodologies to elucidate the dynamics and mechanisms of GPs from multiple filoviruses. We will characterize the mechanisms by which conformational changes, host factors, and environmental variables facilitate filovirus membrane fusion and entry into cells. Completion of the proposed research will provide mechanistic insights into filovirus entry and the viral and host targets that could be exploited with novel therapies and immunogens.