Role of RNA Editing by ADAR1 in Infection

ADAR1 RNA 编辑在感染中的作用

基本信息

批准号：
7232028
负责人：
JINGHUA YANG
金额：
$ 10.49万
依托单位：
BOSTON UNIVERSITY MEDICAL CAMPUS
依托单位国家：
美国
项目类别：
财政年份：
2004
资助国家：
美国
起止时间：
2004-07-15 至 2009-04-30
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/7232028
关键词：
2-5A Synthetase ADAR1 Acute Adenosine Adenoviruses Affect Amanitins Animals Area Award Bacteria Bacterial Pneumonia CXCL1 gene Cell Line Cell physiology Cells Chimera organism Collaborations DNA Microarray Chip DNA Microarray format Dactinomycin Disease Disease model Double-Stranded RNA Down-Regulation Endoribonucleases Endotoxemia Endotoxins Enzymes Genome Heterogeneous Nuclear RNA Host Defense Host Defense Mechanism Immune response Independent Scientist Award Infection Infectious Agent Inflammation Inflammatory Inflammatory Response Inosine Investigation Laboratories Lead Mediating Messenger RNA Mitogen-Activated Protein Kinases Molecular Mus Numbers Pancreatic ribonuclease Pathologic Pathway interactions Phosphoric Monoester Hydrolases Phosphorylation Phosphotransferases Physiological Pneumonia Polymerase Production Productivity Protein Array Protein Biosynthesis Protein Kinase Protein Overexpression Proteins RNA Degradation RNA Editing RNA Processing RNA chemical synthesis Rate Research Reverse Transcriptase Polymerase Chain Reaction Ribonucleases Ribosomal RNA Role Scientist Staging Techniques Thymosin Time Toxin Transgenic Animals Transgenic Mice Translating Up-Regulation Virus adenosine deaminase cell growth eIF-2 Kinase mRNA Precursor mRNA Transcript Degradation macrophage mouse model prevent response skills

项目摘要

DESCRIPTION (provided by applicant): We have previously identified a cellular process that modifies pre-mRNA sequences via an RNA-specific adenosine deaminase or ADAR. Recently, we showed that ADAR1 is induced in macrophages by various infectious agents, including bacteria, viruses, and pathogenic toxins. In mice suffering from endotoxin-induced inflammation, we demonstrate that 5% of the adenosines found in mRNA are converted to inosine. We further show that up to 20% of adenosines in mRNA can be converted to inosine in cells transiently expressing ADAR1. With such high levels of inosine in mRNA, the translated proteins may differ dramatically from those encoded in the genome and the repertoire of protein production could be greatly amplified. RNA processing may also be substantially affected by the presence of inosine. Indeed, we found that the phosphorylation of elF2a is suppressed and the expression of dsRNA protein kinase (PKR) and 2',5'-oligoadenylate synthetase (2'5'OAS) is downregulated in cells that overexpress ADAR1. Therefore, we hypothesize that ADAR1 functions to sustain protein synthesis during infections, and antagonize inflammatory responses at certain stages of infection. Researches to confirm this hypothesis will lead me to disease-oriented studies in transgenic animals that are currently undeveloped in my laboratory. Receipt of the K02 award will allow me to devote 90% of my effort on the proposed research, meaningfully expand my collaborations with high quality scientists, and firmly establish the new lines of investigation to develop skills in these areas and to demonstrate increasing productivity. During award period, we plan to elucidate the physiological function of ADAR1 in modulating host response to infections. The first specific aim is to characterize the role of ADAR1 in disease models of pneumonia and endotoxemia in ADAR1 transgenic mice. Homozygous transgenic mice expressing an ADAR1-EGFP chimera will be produced. Endotoxin and adenovirus-induced acute inflammation will be established and characterized in these animals. The second specific aim proposes to elucidate the mechanism of ADARl-mediated RNA degradation in response to infectious agents. The last aim is to characterize the role of ADAR1 in modulating phosphorylation cascades in the mouse models of pneumonia and endotoxemia using protein array technique.

描述（由申请人提供）：我们之前已经鉴定了一种通过 RNA 特异性腺苷脱氨酶或 ADAR 修饰前 mRNA 序列的细胞过程。最近，我们发现 ADAR1 是由各种感染因子（包括细菌、病毒和致病毒素）在巨噬细胞中诱导的。在患有内毒素诱导炎症的小鼠中，我们证明 mRNA 中发现的腺苷中有 5% 转化为肌苷。我们进一步表明，在瞬时表达 ADAR1 的细胞中，mRNA 中高达 20% 的腺苷可以转化为肌苷。由于 mRNA 中肌苷含量如此之高，翻译后的蛋白质可能与基因组中编码的蛋白质显着不同，并且蛋白质生产的全部能力可能会大大放大。 RNA 加工也可能受到肌苷的存在的显着影响。事实上，我们发现在过表达 ADAR1 的细胞中，elF2a 的磷酸化受到抑制，dsRNA 蛋白激酶 (PKR) 和 2',5'-寡腺苷酸合成酶 (2'5'OAS) 的表达下调。因此，我们假设 ADAR1 的功能是在感染期间维持蛋白质合成，并在感染的某些阶段拮抗炎症反应。证实这一假设的研究将引导我对转基因动物进行以疾病为导向的研究，而这些研究目前在我的实验室中尚未开发。获得 K02 奖将使我能够将 90% 的精力投入到拟议的研究中，有意义地扩大我与高素质科学家的合作，并坚定地建立新的研究路线，以发展这些领域的技能并展示不断提高的生产力。在奖励期间，我们计划阐明 ADAR1 在调节宿主对感染反应中的生理功能。第一个具体目标是表征 ADAR1 在 ADAR1 转基因小鼠肺炎和内毒素血症疾病模型中的作用。将产生表达 ADAR1-EGFP 嵌合体的纯合转基因小鼠。将在这些动物中建立并表征内毒素和腺病毒诱导的急性炎症。第二个具体目标提出阐明ADAR1介导的RNA降解响应感染原的机制。最后一个目标是利用蛋白质阵列技术来表征 ADAR1 在调节肺炎和内毒素血症小鼠模型中磷酸化级联中的作用。