Novel Role for Host Immunostimulatory RNA in Antiviral Immune Defense

项目总结 许多实验室的研究已经证实，DNA传感器--包括膜传感器--定位于 Toll样受体(如TLR9)和细胞内DNA传感器(如cGAs)-感觉型疱疹病毒 感染。与之形成鲜明对比的是，我们对细胞质的生理相关性的认识 RIG-I样受体(RLR)家族的RNA传感器在检测疱疹病毒中的作用，如 单纯疱疹病毒1型(HSV-1)是一种初级病毒。 这项拟议的研究建立在Gack实验室最近的一项发现基础上，即Rig-I在 在检测和限制HSV-1感染中的关键作用，其中RIG-I和细胞内DNA 传感器的作用是暂时的。此外，我们发现在HSV-1感染期间， 宿主来源的5S核糖体RNA假基因转录本141(RNA5SP141)激活RIG-I和 诱导细胞因子介导的抗病毒先天免疫防御。在协作工作方面，我们最近 发现RNA5SP141基因表达缺失与严重的HSV-1相关 人类的脑炎。此外，我们还发现RNA5SP141是从感染的 细胞通过外切体，并被未感染的细胞摄取，在那里它触发RIG-I信号。 结合使用一系列协调的分子、生物化学和细胞生物学方法 利用CRISPR-基因编辑技术，我们将定义RNA5SP141基因表达的作用 在HSV-1感染和HSV-1相关疾病中的抗病毒先天免疫反应 (目标1)。此外，我们还将阐明RNA5SP141的分子机制(S) 胞外体负荷(AIM 2)，并确定胞外体分娩的生理相关性 RNA5SP141在HSV-1感染宿主免疫中的作用(AIM 3)我们的研究将提供一种分子 了解疱疹病毒感染的先天免疫检测，这可能会为 为新的治疗方法奠定基础或指导新佐剂的设计。

PROJECT SUMMARY Work from many laboratories has established that DNA sensors – both membrane-localized Toll-like receptors (e.g. TLR9) and intracellular DNA sensors (e.g. cGAS) – sense herpesvirus infection. In striking contrast, our knowledge about the physiologic relevance of cytoplasmic RNA sensors of the RIG-I-like receptor (RLR) family in the detection of herpesviruses, such as herpes simplex virus type 1 (HSV-1), is rudimentary. The proposed study builds on a recent discovery by the Gack laboratory that RIG-I plays a crucial role in the detection and restriction of HSV-1 infection, where RIG-I and intracellular DNA sensors act in a temporal manner. Furthermore, we identified that during HSV-1 infection the host-derived 5S ribosomal RNA pseudogene transcript 141 (RNA5SP141) activates RIG-I and elicits cytokine-mediated antiviral innate immune defense. In collaborative work we recently identified that ablated RNA5SP141 gene expression is associated with severe HSV-1 encephalitis in humans. Furthermore, we discovered that RNA5SP141 is exported from infected cells via exosomes and taken up by uninfected cells, where it triggered RIG-I signaling. Using a coordinated series of molecular, biochemical, and cell biological approaches combined with CRISPR-gene editing techniques, we will define the role of RNA5SP141 gene expression in the antiviral innate immune response to HSV-1 infection and in HSV-1-associated disease (AIM 1). Furthermore, we will elucidate the molecular mechanism(s) underlying RNA5SP141 exosomal loading (AIM 2), and also determine the physiologic relevance of exosomal delivery of RNA5SP141 in host immunity to HSV-1 infection (AIM 3). Our studies will provide a molecular understanding of innate immune detection of herpesvirus infection, which may provide the foundation for new therapeutic approaches or guide the design of novel adjuvants.