Paramyxovirus Membrane Fusion

描述（由申请人提供）：我们研究的目标是了解 利用纽卡斯尔进行副粘病毒膜融合的分子机制 病毒作为原型。与大多数副粘病毒系统一样， 需要HN和F蛋白。我们的研究集中在F蛋白如何 介导膜融合和HN蛋白在该过程中的作用。我们有 最近提出了四个意见，这些意见直接关系到尚未解决的 关于副粘病毒融合的问题首先，我们发现一个特定的 F蛋白的结构域与HN蛋白的结构域相互作用， 两种蛋白质序列之间相互作用的直接证据， 鉴定所涉及的F蛋白的特定结构域。第二，使用抗血清 特异于F蛋白HR1和HR2结构域，我们已经证明了构象 F蛋白依赖于HN蛋白表达和F蛋白的差异 乳沟第三，使用对HN的短序列特异的肽抗血清， 蛋白质，我们已经证明了HN蛋白相关的构象差异 to F蛋白表达和切割。第四，我们已经使一个点突变， F蛋白消除了对HN蛋白的绝对需求， 合胞体的形成，这一发现提出了关于HN的作用的问题， 融合中的蛋白质附着。为了解决这些发现所提出的问题， 我们提出了四个具体目标：1）表征特定之间的相互作用 HN蛋白和F蛋白的结构域，2）表征构象变化 在与HN蛋白表达和F蛋白切割相关的F蛋白中，3） 表征HN蛋白中与HN蛋白相关的构象变化 附着和F蛋白表达和切割。4)探讨的作用 融合开始时的附着。

DESCRIPTION (Provided by applicant): The goal of our studies is to understand the molecular mechanisms of paramyxovirus membrane fusion using Newcastle disease virus as a prototype. As in most paramyxovirus systems, membrane fusion requires both HN and F proteins. Our studies have focused on how F protein mediates membrane fusion and the role of HN protein in that process. We have recently made four observations that have a direct bearing on unresolved questions about paramyxovirus fusion. First, we have found that a specific domain of the F protein interacts with a domains of the HN protein providing direct evidence for an interaction between sequences from the two proteins and identifying specific domains of the F protein involved. Second, using antisera specific for F protein HR1 and HR2 domains, we have demonstrated conformational differences in F protein dependent upon HN protein expression and F protein cleavage. Third, using peptide antisera specific for a short sequence of the HN protein, we have demonstrated conformational differences in HN protein related to F protein expression and cleavage. Fourth, we have made a point mutant in the F protein that eliminates the absolute requirement for HN protein in syncytia formation, a finding that raises questions about the role of HN protein attachment in fusion. To address the questions raised by these findings we propose four specific aims: 1) characterize interactions between specific domains of the HN protein and F protein, 2) characterize conformational changes in the F protein related to HN protein expression and F protein cleavage, 3) characterize conformational changes in the HN protein related to HN protein attachment and F protein expression and cleavage. 4) explore the role of attachment in initiation of fusion.