Alpha-Herpesvirus Transport in Axons

描述（由申请方提供）：α-疱疹病毒是嗜神经性病原体，包括人病毒水痘-带状疱疹病毒（VZV）和单纯疱疹病毒（HSV）1型和2型，以及动物病毒伪狂犬病病毒（PRV）。这些病毒通过定向轴突运输到外周神经节中的感觉神经元细胞体而传播到神经系统中，在外周神经节中建立终身潜伏感染。感染通常不会危及健康个体的生命，然而，这些病毒具有跨突触传播的能力，通过回路特异性途径进入大脑。一旦进入大脑，所导致的脑炎在大多数情况下是致命的。我研究的长期目标是确定α-疱疹病毒在神经系统中传播的机制，并确定控制疾病结果的因素。这一应用将集中在感觉神经元轴突中的病毒传播。具体而言： 使用感染性克隆诱变方法，将分离在编码每种被膜蛋白的基因中携带突变的病毒。 通过对与绿色荧光蛋白融合的衣壳进行延时跟踪，将筛选突变病毒在轴突中衣壳转运的缺陷。 将启动衣壳转运所需的被膜蛋白的结构/功能分析。 以这种方式，病毒被膜蛋白在衣壳转运中的作用将得到明确的测试。预期这些蛋白质既将衣壳束缚到微管马达上又调节马达活性，因为已知没有其他类型的病毒蛋白质与衣壳结合并同时暴露于宿主胞质溶胶。这些研究的结果将确定α-疱疹病毒如何在感觉神经元内定向移动。这将作为确定病毒转运的分子机制的第一步，并解决脊椎动物神经系统中病毒传播的更大问题。

DESCRIPTION (provided by applicant): Alpha-herpesviruses are neurotropic pathogens that include the human viruses varicella-zoster virus (VZV) and herpes simplex virus (HSV) types 1 and 2, and the animal virus pseudorabies virus (PRV). These viruses spread into the nervous system by directed axonal transport to sensory neuron cell bodies in peripheral ganglia, where life-long latent infections are established. Infections are typically not life threatening in healthy individuals, however, these viruses have the capacity to spread trans-synaptically to enter the brain by circuit-specific routes. Once in the brain, the resulting encephalitis is lethal in the majority of cases. The long-term goals of my studies are to determine the mechanisms by which alpha-herpesviruses spread in the nervous system, and to identify the factors governing disease outcome. This application will focus on virus spread in the axons of sensory neurons. Specifically: Using infectious clone mutagenesis methods, viruses will be isolated carrying mutations in the genes encoding each tegument protein. The mutant viruses will be screened for defects in capsid transport in axons by time-lapse tracking of capsids fused to the green-fluorescence protein. Structure/function analysis of tegument proteins required for capsid transport will be initiated. In this way, the role of the viral tegument proteins in capsid transport will be definitively tested. These proteins are expected to both tether capsids to microtubule motors and regulate motor activity, as no other class of viral proteins are known to associate with capsids and be exposed to the host cytosol simultaneously. The results of these studies will determine how alpha-herpesviruses move directionally within sensory neurons. This will serve as a first step to identifying the molecular mechanisms of viral transport, and to addressing the larger question of virus spread in the vertebrate nervous system.