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: 10378366
• 负责人: Nagaraj Kerur
• 金额: $ 30.54万
• 依托单位: OHIO STATE UNIVERSITY
• 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 2025-11-30
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10378366
• 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 脊椎动物的先天免疫依赖于一组复杂的胞质模式识别受体（PRR）来 检测源自病原体的、进化上保守的分子，例如 DNA。胞质 DNA 的传感 环-GMP-AMP 合酶 (cGAS) 激活环单磷酸鸟苷的酶促合成 单磷酸腺苷 (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 STING，随后招募 TANK 结合激酶 1 (TBK1) 和干扰素 (IFN) 调节因子 3 (IRF3) 可刺激 I 型 IFN 的诱导。虽然最初被认定为 作为外源 DNA 的胞质传感器，cGAS 也被来自染色质片段的募集并激活。 细胞质或微核中的基因组 DNA 受损。 最近多项趋同研究强调了 cGAS 在 DNA 损伤诱导中的重要性 炎症反应及其对细胞衰老、肿瘤发生和转移的影响。没有什么， 然而，我们知道在这些情况下 cGAS 激活是否直接有助于维持 基因组完整性。我们实验室最近的研究发现，cGAS/cGAMP 信号触发 DNA 损伤反应 (DDR)，独立于其特征明确的 I 型干扰素途径。这些 研究表明，cGAMP 诱导的 DDR 激活细胞周期检查点反应，导致 G1 期停滞 以及随后抑制双链 DNA 断裂 (DSB) 的同源定向修复 (HDR) CRISPR/Cas9 编辑的小鼠胚胎以及人类和小鼠细胞。有趣的是，cGAMP 诱导的 DDR 在缺乏干扰素的无脊椎动物物种（牡蛎和小星海葵）中也得到了证实 免疫系统，这表明 cGAMP 的 DNA 损伤监视机制早于它的更完善。 已知IFN介导的免疫功能。 这里提出的研究旨在通过阐明其分子机制来推进这些新发现 cGAS/cGAMP 通过三个主题集成但独立的 DDR 诱导 目标：(1) 解密 参与 cGAMP 诱导的 ATM 激活的关键信号通路； (2) 定义分子 cGAS-cGAMP 诱导的 HDR 抑制机制； (3) 阐明 cGAMP 是否诱导 DDR 增强 cGAS 引发的先天免疫。总之，这项工作将阐明 cGAMP 诱导顶端 DDR 信号激酶 ATM 激活的分子和生化基础，以及 增加对 cGAMP 诱导的 DDR 信号传导与传统免疫之间关系的了解 cGAS 的功能。