Regulatory and Mechanistic Understanding of ADAR-Mediated RNA Editing

ADAR 介导的 RNA 编辑的监管和机制理解

• 批准号: 10630935
• 负责人: Jin Billy Li
• 金额: $ 65.21万
• 依托单位: STANFORD UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-06-01 至 2027-04-30
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10630935
• 关键词: ADAR1; Address; Adenosine; Autoimmune Diseases; Autoimmunity; Biochemical; Biological Assay; Cell Nucleus; Cells; Cytoplasm; Defect; Disease; Double-Stranded RNA; Enzymes; Genetic Screening; In Vitro; Infection; Innate Immune Response; Inosine; Knowledge; Mediating; Molecular; Natural Immunity; Nuclear; Pathogenicity; Pathway interactions; Protein Isoforms; RNA Binding; RNA Editing; Regulation; Testing; fighting; in vivo; innovation; mouse model; pathogen; prevent; sensor; therapeutic development

PROJECT SUMMARY/ABSTRACT The innate immunity is well-controlled to respond to pathogenic infection in a timely and sensitive manner, while tolerating “self” molecules in the cell. Defects in the regulation of innate immunity result in various disorders, such as autoimmune diseases or heightened vulnerability to infections. Previous studies by us and others re- vealed ADAR1, an RNA editing enzyme that catalyzes Adenosine to Inosine (A-to-I) editing on dsRNAs, as a key player in the regulation of innate immune response to double-stranded RNAs (dsRNAs). ADAR1 RNA editing and binding activities have been shown to prevent endogenous (“self”) dsRNAs from activating the cytosolic dsRNA sensors MDA5 and PKR, but the underlying molecular mechanisms are not well understood. In addition, the cytoplasmic editing of at least some dsRNAs by the ADAR1 p150 isoform is crucial to suppress the dsRNA- mediated autoimmunity, although the ADAR1 p110 isoform in the nucleus is generally a lot more abundant. How are these dsRNAs edited in the cytoplasm but not in the nucleus? In this MIRA application, we focus on two projects to address these knowledge gaps. First, we will elucidate the interplay between ADAR1 and other players in the dsRNA innate immunity pathways. Specifically, we will inves- tigate the mechanisms by which ADAR1 regulates the MDA5 and PKR pathways of dsRNA sensing. We propose that ADAR1 regulates dsRNA-mediated innate immunity in both RNA editing-dependent and -independent fash- ion. We will study how these two modes of action operate in vitro and test their in vivo implications in mouse models. Second, we will uncover the regulatory mechanisms for cytoplasmic vs. nuclear editing. Specifically, we will perform genetic screens and biochemical assays to identify and characterize the factors responsible for spatial differences in editing. Taken together, these innovative studies will provide a deep understanding of the molecular mechanisms operating at the interface of dsRNA editing and dsRNA sensing in innate immunity.

项目摘要/摘要 先天的免疫力得到很好的控制，可以及时响应致病性感染，而 耐受细胞中的“自我”分子。与先天免疫调节的缺陷导致各种疾病， 例如自身免疫性疾病或增加感染的脆弱性。我们和其他人的先前研究重新 Vealed Adar1，一种RNA编辑酶，将腺苷催化为inosine（A-to-I）编辑DSRNA，作为A 对双链RNA（DSRNA）的先天免疫反应调节的关键参与者。 ADAR1 RNA编辑 结合活性已被证明可以防止内源性（“自我”）DSRNA激活胞质 DSRNA传感器MDA5和PKR，但是尚不清楚潜在的分子机制。此外， ADAR1 P150同工型对至少一些DSRNA的细胞质编辑对于抑制DSRNA-至关重要 介导的自身免疫性，尽管核中的ADAR1 P110同工型通常更丰富。如何 这些DSRNA是否在细胞质中编辑，但在细胞核中不编辑？ 在此MIRA应用程序中，我们专注于两个项目来解决这些知识差距。首先，我们将阐明 DSRNA先天免疫道路中ADAR1与其他玩家之间的相互作用。具体来说，我们将提出 - 探讨ADAR1调节DSRNA敏感性的MDA5和PKR途径的机制。我们建议 ADAR1调节DSRNA介导的RNA编辑依赖性和非依赖性fash-的先天免疫力 离子。我们将研究如何在体外进行这两种动作模式，并测试其在小鼠中的体内含义 型号。其次，我们将发现细胞质与核编辑的调节机制。具体来说，我们 将执行遗传筛选和生化测定，以识别和表征负责的因素 编辑方面的空间差异。综上所述，这些创新的研究将对 在dsRNA编辑和先天免疫中传感的界面上运行的分子机制。