Investigating the Antiviral Role of STING During Enteric RNA Virus Infection in Drosophila

研究 STING 在果蝇肠道 RNA 病毒感染过程中的抗病毒作用

• 批准号: 10219056
• 负责人: Elisha Segrist
• 金额: $ 1.55万
• 依托单位: UNIVERSITY OF PENNSYLVANIA
• 依托单位国家: 美国
• 财政年份: 2019
• 资助国家: 美国
• 起止时间: 2019-08-01 至 2021-12-22
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10219056
• 关键词: Alphavirus; Antiviral Agents; Arboviruses; Autophagocytosis; Bacteria; Bacterial Infections; Binding; Biological Assay; Bite; Blood; Cause of Death; Culicidae; Cyclic GMP; DNA; DNA Binding; DNA Binding Domain; DNA Virus Infections; DNA Viruses; Data; Dinucleoside Phosphates; Drosophila genus; Enteral; Enterocytes; Epithelial; Evolution; Future; Gene Activation; Genes; Genetic Transcription; Health; Homologous Gene; Human; Immune; Immune response; Immunity; Infection; Inflammatory; Innate Immune Response; Interferons; Intestines; Lead; Ligands; Light; Link; Mammals; Medical; Metagenomics; Microscopy; Monitor; NF-kappa B; Neurons; Oral; Orthologous Gene; Pathway interactions; Periodicity; Play; Predisposition; RNA Binding; RNA Virus Infections; RNA Viruses; Role; Sequence Analysis; Signal Transduction; Sindbis Virus; Stimulator of Interferon Genes; Stomatitis; TBK1 gene; Testing; Therapeutic; Virus; Virus Diseases; Work; antimicrobial; base; burden of illness; commensal bacteria; defined contribution; enteric infection; enteric virus infection; feeding; fly; gastrointestinal epithelium; human model; improved; in vivo Model; intestinal barrier; intestinal epithelium; microbiome; microbiota; mosquito-borne; novel therapeutic intervention; oral infection; pathogen; response; vector mosquito; viral RNA

Project Summary: The intestine serves as a physical and immune barrier to protect against infection by enteric pathogens. The Cherry lab uses Drosophila as an in vivo model of human and mosquito enteric infection to understand the intestinal innate immune response and how it is influenced by the composition of the microbiota. Sindbis virus is a mosquito-borne virus that is transmitted to mosquito vectors orally during a blood meal. Our preliminary data suggest the Drosophila homologue of Stimulator of Interferon Genes (STING) is antiviral against Sindbis virus within the intestine. Mammalian STING is activated by binding cyclic dinucleotides produced endogenously by cyclic GMP-AMP synthase (cGAS) or exogenously by bacteria. Mammalian cGAS produces a cyclic dinucleotide after binding cytosolic DNA from bacteria or DNA viruses but is not activated by binding RNA. Our preliminary data shows that the closest cGAS ortholog is antiviral against enteric Sindbis infection. Sequence analysis of this Drosophila cGAS candidate reveals it lacks the DNA binding domain found in mammalian cGAS, suggesting that d-cGAS senses a non-DNA ligand, perhaps viral RNA. Metagenomic data reveals that Drosophila commensal bacteria encode CDN synthases indicating that the microbiota could provide an exogenous CDN pool to prime basal STING activity from subsequent viral infection. Indeed, our preliminary data suggests exogenous feeding of CDNs to flies lacking their microbiota protects against enteric Sindbis virus infection. Moreover, we found that STING may be antiviral through the activation of autophagy and inflammatory NF-kB activation. We hypothesize that both d-cGAS and the microbiome produce CDNs that activate dSTING to protect from RNA virus infection through infection-dependent autophagy within the intestine. To expand on this hypothesis in Aim 1 we propose to determine the role of d-cGAS and CDNs in STING-dependent antiviral defense. Additionally, in Aim 2 we propose to define the mechanism by which STING is antiviral in enterocytes. This work sheds light on evolution of the ancient cGAS- STING defense pathway and defines how additional microbiota-derived products, such as CDNs, may influence intestinal immunity.

项目摘要： 肠道是防止肠感染的物理和免疫屏障 病原体。樱桃实验室使用果蝇作为人类和蚊子的体内模型 感染以了解肠道的先天免疫反应及其如何影响。 菌群的组成。信德氏病毒是一种传播到蚊子传播的病毒 蚊子媒介在血液粉期间口服。我们的初步数据表明果蝇 干扰素基因刺激剂（STING）的同源物是针对Sindbis病毒的抗病毒 肠。哺乳动物的刺激通过结合循环二核苷酸被激活 通过环状GMP-AMP合酶（CGA）或细菌外源。哺乳动物CGA产生 结合细菌或DNA病毒的胞质DNA后的环状二核苷酸，但未激活 通过结合RNA。我们的初步数据表明，最近的CGA直系同源物是抗病毒 肠道感染。该果蝇CGA候选者的序列分析表明它缺乏 在哺乳动物CGA中发现的DNA结合结构域，表明D-CGAS感觉到非DNA 配体，也许是病毒RNA。宏基因组数据表明果蝇分子细菌 编码CDN合酶，表明微生物群可以提供外源性CDN池 随后的病毒感染产生的主要基础刺激活性。确实，我们的初步数据建议 将CDN的外源喂养到缺乏其微生物群防止肠子的Sindbis病毒的果蝇 感染。此外，我们发现通过自噬的激活可能是抗病毒 和炎症NF-KB激活。 我们假设D-CGA和微生物组都会产生将DSTINT激活至的CDN 通过肠内感染依赖性自噬来保护RNA病毒感染。到 在AIM 1中扩展这一假设，我们建议确定D-CGA和CDN在 依赖sting的抗病毒防御。此外，在AIM 2中，我们建议定义机制 在肠上细胞中刺激性抗病毒。这项工作阐明了古代CGA的演变 sting防御途径并定义了其他微生物群衍生产品（例如CDN）如何 可能影响肠道免疫。