Cell stress-mediated changes in the Herpes simplex virus type 1 chromatin structure during reactivation from latent infection

项目摘要/摘要 单纯疱疹病毒(HSV)以潜伏感染的形式在周围神经元中持续存在。作为回应 对于神经元压力，病毒会从潜伏期重新激活，从而允许再次感染。重新激活与 重大疾病。例如，重新激活后在角膜中的复制会导致角膜炎。 激活后传播到中枢神经系统可导致单纯疱疹病毒性脑炎 (HSE)。如果不治疗，HSE的病死率为70%，即使接受治疗，许多幸存者也表现出 长期的后遗症。尽管有抗病毒药物可以限制HSV的生产性复制，但没有治疗方法 以感染潜伏期为目标，防止再激活，目前还没有针对HSV的疫苗。因此，我们的 长期目标是了解单纯疱疹病毒对神经元压力的反应，并制定预防策略 正在进行重新激活。我们的实验室和其他人已经证明了病毒基因表达的机制 在重新激活期间的启动不同于病毒的从头感染。我们发现一种神经元 C-jun氨基末端激酶(JNK)激活的应激途径触发病毒染色质的变化 并允许重新激活。具体地说，与病毒启动子相关的组蛋白保持了修饰 与异染色质(H3K9me3)相关，但也在JNK依赖的H3S10上被磷酸化 举止。使用我们建立的HSV-1潜伏期的初级神经元模型和小鼠模型 我们将确定JNK的激活如何在感染期间诱导病毒基因表达 重新激活。通过对候选蛋白质进行芯片序列和shRNA敲除，我们将研究JNK是如何 被招募为病毒启动者，并确定参与HSV-1重新激活的其他细胞蛋白。我们会 还要确定JNK信号如何克服H3K27me3抑制组蛋白药物来允许 从与此修饰相关的基因组中重新激活。最后，我们将研究 ATRX限制HSV-1重新激活并验证与ATRX相关的基因组是非 允许重新激活。这些研究是关于潜伏的病毒基因组和 神经元应激反应的启动尤其重要，因为它们提供了对如何 病毒经历了重新激活。因为病毒很可能通过细胞途径来实现 在重新激活的过程中，我们还将揭示对宿主对神经元应激做出反应的重要过程。 重要的是，通过了解HSV重新激活的最早事件，我们的长期目标是发展 针对潜在基因组并使其对重新激活无反应的治疗方法。

Project Summary/abstract Herpes simplex virus (HSV) persists for life in peripheral neurons in the form of a latent infection. In response to neuronal stress, the virus reactivates from latency to permit reinfection. Reactivation is associated with significant disease. For example, replication in the cornea following reactivation results in keratitis. Transmission to the central nervous system following reactivation can result in herpes simplex encephalitis (HSE). Without treatment, HSE has a fatality rate of 70%, and even with treatment, many survivors exhibit long-term sequelae. Although anti-viral drugs are available that limit HSV productive replication, no therapies target the latent stage of infection to prevent reactivation and there is no vaccine against HSV. Therefore, our long-term goals are to understand how HSV responds to neuronal stress and develop strategies to prevent reactivation occurring. Our lab and others have shown that the mechanism by which viral gene expression initiates during reactivation is distinct from de novo infection with the virus. We have found that a neuronal stress pathway resulting in activation of c-Jun N-terminal kinase (JNK) triggers changes to the viral chromatin and permits reactivation. Specifically, the histones associated with viral promoters maintained a modification associated with heterochromatin (H3K9me3) but also became phosphorylated on H3S10 in a JNK-dependent manner. Using both a primary neuronal model of HSV-1 latency that we have developed and mouse models of infection we will determine how activation of JNK permits viral gene expression to be induced during reactivation. By performing ChIP-seq and shRNA knock-down of candidate proteins, we will examine how JNK gets recruited to viral promoters and identify additional cellular proteins involved in HSV-1 reactivation. We will also determine how JNK signaling overcomes the H3K27me3 repressive histone medication to permit reactivation from genomes associated with this modification. Finally, we will examine the mechanism that ATRX restricts HSV-1 reactivation and test the hypothesis that genomes associated with ATRX are non- permissive for reactivation. These studies into the intimate interaction between the latent viral genome and initiation of a neuronal stress response are especially significant as they provide mechanistic insight into how the virus undergoes reactivation. Because the virus has likely co-opted cellular pathway to achieve reactivation, we will also uncover process that are important for the host response to neuronal stress. Importantly, by understanding the very earliest events in HSV reactivation, our long-term goals are to develop therapies that target the latent genome and make it unresponsive for reactivation.