The role of mammarenavirus defective interfering particles in protecting host fitness and the host-driven post-translational modifications that regulate their formation and function

RNA病毒的关键发现，如双节，单链沙粒病毒家族，产生 50多年前，有缺陷的干扰颗粒（DIP）促使人们研究它们对病毒的贡献。 发病机制和宿主免疫。然而，许多基本问题仍然存在，包括 DIPs是如何被调节的，以及DIPs对病毒-宿主相互作用的贡献，包括DIPs的持续存在。 人畜共患病原体在其储存宿主。我们的总体目标是确定负责 调节沙粒病毒DIP生产，并询问DIP对储层适合性的影响。一个主要 了解DIP在病毒发病机制和疾病生态学中的真正作用的限制是缺乏工具 以调节实验系统中的DIP水平。我们最近发现LCMV使用不同的细胞 产生标准病毒颗粒与DIP的途径。利用反向遗传系统，我们发现 强大的宿主驱动的翻译后修饰（PTM），动态调节 感染性病毒颗粒与缺陷性病毒颗粒。这些研究使我们能够第一次， 不再产生DIP的沙粒病毒。我们的具体目标将是利用这些创新方法 和工具来1）定义宿主酪氨酸激酶和NEDD 4家族E3泛素连接酶 调节DIP的形成和功能，2）扩大我们可能影响DIP的沙粒病毒PTM的全球地图 生产，和3）将这些分子发现与建模持续性感染 啮齿动物宿主的感染和啮齿动物或偶然人类宿主的急性感染。大多数RNA病毒感染 动物产生DIP，这表明它们对这些病毒的维持至关重要 在自然界中。我们的研究结果将广泛适用于布尼亚病毒目以外。总的来说， 这些研究将为DIP生产的监管提供更大的解决方案，并首次回答， DIP在病毒持久性中的作用。

The pivotal discovery of RNA viruses, like the bi-segmented, single-stranded arenavirus family, producing defective interfering particles (DIPs) over 50 years ago prompted investigations on their contribution to viral pathogenesis and host immunity. However, many basic questions remain, including the molecular basis for how DIPs are regulated and the contribution of DIPs to virus–host interactions, including the persistence of zoonotic pathogens in their reservoir host. Our overall goal is to identify the cellular machinery responsible for regulating arenavirus DIP production and interrogate the impact DIPs have on reservoir fitness. A major constraint to understanding the true role of DIPs in viral pathogenesis and disease ecology is the lack of tools to modulate DIP levels in experimental systems. We recently discovered that LCMV uses divergent cellular pathways to produce standard virus particles versus DIPs. Using reverse genetic systems, we identified powerful host-driven post-translational modifications (PTMs) that dynamically regulate the production of infectious versus defective viral particles. These studies enabled us to engineer, for the first time, recombinant arenaviruses that no long produce DIPs. Our specific objectives will be to use these innovative approaches and tools to 1) define the mechanism by which host tyrosine kinases and NEDD4 Family E3 ubiquitin ligases regulate DIP formation and function, 2) expand our global map of arenavirus PTMs that may influence DIP production, and 3) connect these molecular findings to pathogenesis studies modeling both persistent infection of the rodent reservoir and acute infection of the rodent or incidental human host. Most RNA viruses that infect animals produce DIPs, which suggests they are fundamentally important for the maintenance of these viruses in nature. Our findings will be broadly applicable beyond the Bunyavirales order. Collectively, the completion of these studies will provide greater resolution on the regulation of DIP production and answer, for the first time, the role of DIP in viral persistence.