Non-canonical cGAS signaling in DNA damage response

DNA 损伤反应中的非典型 cGAS 信号传导

• 批准号: 10064992
• 负责人: Nagaraj Kerur
• 金额: $ 18.55万
• 依托单位: UNIVERSITY OF VIRGINIA
• 依托单位国家: 美国
• 财政年份: 2019
• 资助国家: 美国
• 起止时间: 2019-12-05 至 2021-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10064992
• 关键词: ATM activation; Address; Adenosine Monophosphate; Affinity; Aging; Antiviral Agents; Apical; Binding; Biochemical; Biological Process; CHEK1 gene; CHEK2 gene; CRISPR/Cas technology; Cell Aging; Cell Cycle; Cell Cycle Arrest; Cell Cycle Checkpoint; Cells; Chemical Agents; Chromatin; Complex; Cyclic GMP; Cytosol; DNA; DNA Damage; DNA Repair; DNA biosynthesis; DNA strand break; Data; Defense Mechanisms; Deltastab; Dimerization; Dinucleoside Phosphates; Disulfides; Embryo; Endoplasmic Reticulum; Enzymes; Eukaryotic Cell; Exposure to; Foundations; G1 Arrest; Generations; Genes; Genetic Transcription; Genome; Genomic DNA; Genomic Instability; Guanosine Monophosphate; Guanosine Triphosphate; HTATIP gene; Histones; Homeostasis; Human; IFNAR1 gene; IRF3 gene; Immune system; Immunologic Receptors; Inflammatory; Inflammatory Response; Interferon Type I; Interferons; Invertebrates; Laboratories; Lead; Left; Lymphocyte; Maintenance; Malignant Neoplasms; Manuscripts; Mediating; Mediator of activation protein; Membrane Proteins; Mitotic; Molecular; Mus; Natural Immunity; Neoplasm Metastasis; Nucleotides; Operating System; Oxidative Stress; Oysters; Pathway interactions; Pattern recognition receptor; Periodicity; Process; Role; STAT2 gene; Sea Anemones; Second Messenger Systems; Signal Pathway; Signal Transduction; Stimulus; System; TANK-binding kinase 1; TP53 gene; Telomerase; V(D)J Recombination; Work; assault; ataxia telangiectasia mutated protein; base; brca gene; crosslink; ds-DNA; endodeoxyribonuclease SceI; genome integrity; immune function; insight; novel; pathogen; receptor; recruit; repaired; response; sensor; tumorigenesis

SUMMARY The vertebrate innate immunity relies upon a complex set of cytosolic pattern recognition receptors (PRR) to detect pathogen-derived, evolutionarily conserved molecules such as DNA. The sensing of cytosolic DNA by cyclic-GMP-AMP synthase (cGAS) activates the enzymatic synthesis of cyclic guanosine monophosphate- adenosine monophosphate (cGAMP), a cyclic dinucleotide (CDN) second messenger. cGAMP signals via its high affinity receptor protein STING, which subsequently recruits TANK-binding kinase 1 (TBK1) and interferon (IFN) regulatory factor 3 (IRF3) to stimulate the induction of type I IFNs. Although originally identified as a cytosolic sensor of foreign DNA, cGAS is also recruited to and activated by fragments of chromatin from damaged genomic DNA in the cytosol or micronuclei. Multiple convergent studies have recently highlighted the significance of cGAS in the DNA damage–induced inflammatory response and its implications for cellular senescence, tumorigenesis, and metastasis. Nothing, however, is known about whether cGAS activation in these contexts directly contributes to the maintenance of genome integrity. Recent studies in our laboratory have discovered that cGAS/cGAMP signaling triggers DNA damage response (DDR), independently of its well-characterized type I interferon pathway. These studies revealed that cGAMP-induced DDR activates cell cycle checkpoint responses that lead to G1 arrest and subsequent suppression of homology directed repair (HDR) of double-strand DNA breaks (DSB) in CRISPR/Cas9-edited mouse embryos and human and mouse cells. Interestingly, the cGAMP-induced DDR was also demonstrable in invertebrate species (oysters and starlet sea anemone) lacking interferon-based immune system, suggesting that the DNA damage surveillance mechanism of cGAMP predates its more well- known IFN-mediated immune function. The studies proposed here aim to advance these novel findings by elucidating the molecular mechanism of cGAS/cGAMP-induced DDR induction via three thematically integrated, yet independent Aims: (1) Decipher the critical signaling pathways involved in cGAMP-induced ATM activation; (2) Define the molecular mechanism of cGAS-cGAMP-induced suppression of HDR; and (3) Elucidate whether cGAMP-induced DDR potentiates the cGAS-initiated innate immunity. In summary, this work will illuminate novel aspects of the molecular and biochemical basis of cGAMP-induced activation of the apical DDR signaling kinase ATM, and increase understanding of the relationship between cGAMP-induced DDR signaling and the traditional immune function of cGAS.

概括 脊椎动物先天免疫依赖于一组复杂的胞质模式识别受体（PRR） 检测病原体衍生的，进化保守的分子，例如DNA。通过 环状GMP-AMP合酶（CGA）激活环状鸟苷单磷酸的酶促 腺苷一磷酸腺苷（CGAMP），一种环状二核苷酸（CDN）第二信使。 CGAMP信号通过其 高亲和力受体蛋白刺，随后募集储罐结合激酶1（TBK1）和干扰素 （IFN）调节因子3（IRF3）刺激I型IFN的诱导。尽管最初被确定为 外国DNA的胞质传感器，CGA还被染色质的片段募集到并激活 细胞质或微核中受损的基因组DNA。 多项收敛研究最近强调了CGA在DNA损伤诱导的 炎症反应及其对细胞感应，肿瘤发生和转移的影响。没有什么， 但是，知道在这些情况下的CGA激活是否直接有助于维护 基因组完整性。我们实验室的最新研究发现CGA/CGAMP信号传导触发器 DNA损伤反应（DDR），独立于其特征型I型干扰素途径。这些 研究表明，CGAMP诱导的DDR激活导致G1停滞的细胞周期检查点响应 并随后抑制同源性的定向修复（HDR）双链DNA断裂（DSB） CRISPR/CAS9编辑的小鼠胚胎以及人和小鼠细胞。有趣的是，CGAMP诱导的DDR 在缺乏基于干扰的无脊椎动物物种（牡蛎和星际海葵）中也可以证明 免疫系统，表明CGAMP的DNA损伤监视机制提出了更良好的 已知的IFN介导的免疫功能。 这里提出的研究旨在通过阐明分子机制来推动这些新发现 CGA/CGAMP诱导的DDR诱导通过三个主题集成但独立的目的：（1）编译 CGAMP诱导的ATM激活涉及的临界信号通路； （2）定义分子 CGAS-CGAMP诱导HDR抑制的机制； （3）阐明CGAMP诱导的DDR是否 增强CGAS引发的先天免疫力。总而言之，这项工作将阐明 CGAMP诱导的顶端DDR信号激酶ATM的激活的分子和生化基础， 对CGAMP诱导的DDR信号与传统免疫之间的关系的了解不断增加 CGA的功能。