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

基本信息

批准号：
10003008
负责人：
Elisha Segrist
金额：
$ 4.55万
依托单位：
UNIVERSITY OF PENNSYLVANIA
依托单位国家：
美国
项目类别：
财政年份：
2019
资助国家：
美国
起止时间：
2019-08-01 至 2022-07-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/10003008
关键词：
Alphavirus Antiviral Agents Arboviruses Autophagocytosis Bacteria Bacterial Infections Binding Biological Assay Bite Blood Cause of Death Cherry - dietary Culicidae Cyclic GMP DNA DNA Binding DNA Binding Domain DNA Virus Infections DNA Viruses Data Dinucleoside Phosphates Drosophila genus Enteral Enterocytes Epithelial Epithelium 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 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

项目摘要

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.

项目概要：肠道作为物理和免疫屏障，可防止肠道感染病原体。 Cherry 实验室使用果蝇作为人类和蚊子肠道的体内模型感染以了解肠道先天免疫反应及其如何受到感染的影响微生物群的组成。辛德比斯病毒是一种通过蚊媒传播的病毒吸血期间经口传播的蚊媒。我们的初步数据表明果蝇干扰素基因刺激物 (STING) 的同源物对辛德毕斯病毒具有抗病毒作用肠。哺乳动物 STING 通过结合内源产生的环状二核苷酸来激活由环 GMP-AMP 合酶 (cGAS) 或外源性细菌产生。哺乳动物 cGAS 产生结合细菌或DNA病毒胞质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，最接近的 cGAS 直系同源物具有抗病毒作用肠道辛德毕斯感染。该果蝇 cGAS 候选物的序列分析表明它缺乏在哺乳动物 cGAS 中发现的 DNA 结合域，表明 d-cGAS 可以感知非 DNA 配体，也许是病毒RNA。宏基因组数据表明果蝇共生细菌编码 CDN 合酶，表明微生物群可以提供外源 CDN 池后续病毒感染的主要基础 STING 活性。事实上，我们的初步数据表明向缺乏微生物群的果蝇外源喂养 CDN 可预防肠道辛德比斯病毒感染。此外，我们发现STING可能通过激活自噬来抗病毒和炎症 NF-kB 激活。我们假设 d-cGAS 和微生物组都会产生激活 dSTING 的 CDN 通过肠道内感染依赖性自噬来防止 RNA 病毒感染。到在目标 1 中扩展这一假设，我们建议确定 d-cGAS 和 CDN 在 STING 依赖性抗病毒防御。此外，在目标 2 中，我们建议定义机制 STING 在肠细胞中具有抗病毒作用。这项工作揭示了古代 cGAS 的演化 STING 防御途径并定义了其他微生物衍生产品（例如 CDN）如何可能会影响肠道免疫力。