Regulation and Function of Nuclear cGAS

核cGAS的调节和功能

• 批准号: 10686032
• 负责人: Daniel B Stetson
• 金额: $ 62.39万
• 依托单位: UNIVERSITY OF WASHINGTON
• 依托单位国家: 美国
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-09-22 至 2025-08-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10686032
• 关键词: Amino Acids; Applications Grants; Autoimmune Diseases; Base Pairing; Biology; Biotinylation; Cell Cycle; Cells; Chimeric Proteins; Chromatin; Cytosol; DNA; DNA Virus Infections; DNA Viruses; Detection; Discrimination; Genomic DNA; Host Defense; Human; Human Cell Line; Infection; Knock-in Mouse; Label; Ligands; Mediating; Mus; Mutation; Nature; Nuclear; Nuclear Protein; Nucleic Acids; Pathway interactions; Phase; Proteins; RNA; Regulation; Resistance; Rest; Sodium Chloride; Stimulator of Interferon Genes; Surface; Tumor Immunity; Untranslated RNA; Viral Proteins; Virus Diseases; autoreactivity; innovation; insight; mouse model; new therapeutic target; prevent; response; sensor; temporal measurement; tool

Project Summary/Abstract Detection of intracellular DNA by the cGAS-STING pathway mediates host defense against DNA viruses, contributes to specific human autoimmune diseases, and can be harnessed to promote anti-tumor immunity. The presence of billions of base pairs of genomic DNA in all nucleated cells raises the question of how cGAS is not constitutively activated. A widely accepted explanation for this is the sequestration of cGAS in the cytosol, which is thought to prevent cGAS from accessing nuclear DNA. We have found that endogenous cGAS is predominantly a nuclear protein, regardless of cell cycle phase or cGAS activation status. We show that nuclear cGAS is tethered tightly by a salt-resistant interaction. This tight tethering is independent of the domains required for cGAS activation, and it requires intact nuclear chromatin. We identify the evolutionarily conserved tethering surface on cGAS and we show that mutation of single amino acids within this surface renders cGAS massively and constitutively active against self-DNA. Thus, tight nuclear tethering maintains the resting state of cGAS and prevents autoreactivity, revealing a fundamental mechanism that controls the resting state of cGAS. In this grant application, we have developed innovative new tools to define the cGAS nuclear tethering compartment, quantitate changes in cGAS disposition during DNA virus infection, and explore cGAS- associated nucleic acids before and after its activation in the context of infection and autoimmune disease. Our studies will uncover fundamental new aspects of cGAS biology, will identify new targets for therapeutic modulation of cGAS activity, and will provide new insights into the principles of self/non-self discrimination by intracellular nucleic acid sensors.

项目摘要/摘要 通过CGAS-Sting途径检测细胞内DNA，介导宿主防御DNA病毒， 有助于特定的人类自身免疫性疾病，并可以利用以促进抗肿瘤免疫力。 在所有成核细胞中存在数十亿对基因组DNA的基础对提出了CGA的问题 没有组成式激活。一个广泛接受的解释是CGA在细胞质中的隔离， 人们认为可以防止CGA进入核DNA。我们发现内源性CGA是 无论细胞周期阶段或CGAS活化状态如何，主要是核蛋白。我们表明 核CGA通过耐盐的相互作用紧密束缚。这种紧身的绑扎与 CGA激活所需的域，并且需要完整的核染色质。我们从进化上识别 在CGA上保守的绑扎表面，我们表明该表面内的单个氨基酸的突变 呈现CGA的大规模和组成型反对自动-DNA。因此，紧密的核束缚保持 CGA的休息状态并防止自动反应性，揭示了控制静止的基本机制 CGA状态。 在此赠款申请中，我们开发了创新的新工具来定义CGAS核束缚 隔室，定量DNA病毒感染期间CGAS处置的变化，并探索CGAS- 相关的核酸在感染和自身免疫性疾病的情况下激活前后。我们的 研究将发现CGA生物学的基本新方面，将确定治疗的新目标 调节CGA活动，并将提供有关自我/非自我歧视原则的新见解 细胞内核酸传感器。