Post-Initiation control of transcription in inflammatory macrophages

炎症巨噬细胞转录起始后控制

• 批准号: 10302293
• 负责人: INEZ ROGATSKY
• 金额: $ 59.08万
• 依托单位: HOSPITAL FOR SPECIAL SURGERY
• 依托单位国家: 美国
• 财政年份: 2019
• 资助国家: 美国
• 起止时间: 2019-12-23 至 2024-11-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10302293
• 关键词: Acute; Anti-Inflammatory Agents; Autoimmune Diseases; Behavior; Binding; Cartilage; Cells; Chemicals; Chromatin; Chronic; Complex; Data; Dependence; Disease; Endotoxins; Enhancers; Enzymes; Epigenetic Process; Equilibrium; Future; GC gene; Gene Expression; Genes; Genetic; Genetic Transcription; Glucocorticoid Receptor; Glucocorticoids; Goals; Health; Hyperactivity; Immune; Immunity; In Vitro; Inflammation; Inflammation Mediators; Inflammatory; Inflammatory Arthritis; Inflammatory Response; Invaded; Ligand Binding; Malignant - descriptor; Malignant Neoplasms; Mediating; Modeling; Molecular; Mus; Pathogenesis; Pathology; Pathway interactions; Patient Care; Peritonitis; Pharmaceutical Preparations; Pharmacology; Phosphorylation; Phosphotransferases; Play; Polymerase; Positive Transcriptional Elongation Factor B; Pre-Clinical Model; Progressive Disease; Proliferating; Proteins; Publishing; RNA; RNA Polymerase II; Regulation; Reporting; Repression; Rheumatoid Arthritis; Role; Shock; Signal Transduction; Testing; Therapeutic; Therapeutic Glucocorticoid; Time; Tissues; Toxic effect; Transcription Elongation; Transcription Factor AP-1; Transcription Initiation; Transcriptional Regulation; Translating; Work; activating transcription factor; anticancer research; arthropathies; attenuation; bone; cancer therapy; cyclin T1; factor EF-P; gene induction; genome-wide; glucocorticoid receptor alpha; in vivo; inhibitor; insight; macrophage; mouse model; negative elongation factor; neoplastic cell; novel; novel therapeutic intervention; promoter; receptor; recruit; response; small molecule; transcription factor; transcriptome; tumor

Macrophage (MΦ)-driven inflammation is at the core of autoimmune diseases including rheumatoid arthritis (RA), signifying imbalance between circuits that turn inflammatory genes on and off. The `on' state is conferred by transcription factors such as NFκB that activate basal transcription machinery and chromatin at pro- inflammatory enhancers and promoters. An equally robust `off' signal is conveyed by the glucocorticoid (GC) receptor (GR) which, upon ligand binding, tethers to NFκB and represses its targets. Notably, these genes form distinct classes: those for which RNA polymerase (Pol) II recruitment and transcription initiation are rate- limiting, and those whose promoters are pre-loaded by initiated but paused Pol II and pause-enforcing factors, NELF and DSIF. Pause-release requires the positive elongation factor, P-TEFb, a kinase that phosphorylates Pol II, NELF and DSIF leading to NELF release and productive elongation. Importantly, assembly of the Pol II- NELF-DSIF `paused complex' is tightly regulated by another kinase, CDK7. To date, the role of post-initiation control of transcription in immunity and disease is unknown. Our preliminary data in MΦ reveal transcriptome- wide Pol II pausing and unexpectedly dynamic behavior of NELF upon inflammatory stimulation. NELF deletion dramatically shifted the balance of pro- and anti-inflammatory mediators and blunted inflammatory responses over time. The pausing complex is also a critical target of GC - the cornerstone of anti-inflammatory therapies. Although basal machinery and chromatin were once considered too general to be `druggable', pioneering work in cancer research uncovered the benefits of targeting epigenetic regulators and, more recently, CDK7. In RA, the transformation of the synovial lining into aggressively proliferating cartilage- and bone-invading tissue is often viewed as malignant. Like tumor cells, synovial MΦ enter a state of transcriptional dependency with a few super-enhancers dominating the inflammatory transcriptome. These data point to CDK7 inhibition as a novel promising avenue to treat RA as a monotherapy or in combination with GC. Our objective is to dissect the specific contribution of post-initiation control to inflammation - in MΦ and in mouse models of RA. Our central hypothesis is that pausing plays an essential `permissive' role in MΦ-driven inflammation by constraining anti- inflammatory gene expression. We further propose that genetic and pharmacologic manipulation of Pol II pausing will yield important insights into the pathogenesis of inflammatory diseases such as RA, with potential to be translated into advances in patient care. Our Specific Aims are to: 1. Dissect the role of the pause- release checkpoint in inflammatory gene induction in MΦ; 2. Evaluate early elongation and higher-order chromatin interactions in MΦ as targets for GR; 3. Assess the utility of manipulating elongation control in vivo using inflammatory arthritis models. The successful completion of this project will: i) reveal the contribution of Pol II pausing to inflammatory MΦ activation; ii) help refine the anti-inflammatory actions of GC; iii) uncover the potential of new therapeutic strategies targeting the early elongation checkpoint in preclinical models of RA.

巨噬细胞（MΦ）驱动的炎症是包括类风湿性关节炎在内的自身免疫性疾病的核心 (RA)这意味着启动和关闭炎症基因的回路之间的不平衡。“开启”状态被赋予 通过转录因子如NFκB激活基础转录机制和染色质在前 炎症增强剂和促进剂。糖皮质激素（GC）也传递同样强有力的“关闭”信号。 受体（GR），其在配体结合后束缚NFκB并抑制其靶点。这些基因 形成不同的类别：那些RNA聚合酶（Pol）II招募和转录起始是速率- 限制性的，以及那些其启动子被启动但暂停的Pol II和暂停强制因子预加载的， NELF和DSIF。暂停释放需要正延伸因子P-TEFb，一种磷酸化 Pol II、NELF和DSIF导致NELF释放和有效伸长。重要的是，Pol II的组装- NELF-DSIF“暂停复合物”由另一种激酶CDK 7严格调节。迄今为止， 免疫和疾病中的转录控制是未知的。我们在MΦ中的初步数据显示转录组- 广泛的Pol II暂停和NELF在炎症刺激后的意外动态行为。NELF缺失 显著改变了促炎和抗炎介质的平衡，并减弱了炎症反应 随着时间停顿复合物也是GC的关键目标-抗炎疗法的基石。 虽然基础机器和染色质曾经被认为太普遍而不能“药物”，但开创性的工作 在癌症研究中发现了靶向表观遗传调节因子的好处，最近，CDK 7。在RA中， 滑膜衬里转化为积极增殖的软骨和骨侵入组织， 常被视为恶性。与肿瘤细胞一样，滑膜MΦ进入转录依赖状态， 控制炎症转录组的超级增强子这些数据表明CDK 7抑制是一种新的 作为单一疗法或与GC组合治疗RA的有希望的途径。我们的目标是解剖 启动后控制对炎症的特定贡献-在MΦ和RA小鼠模型中。我们的中央 一种假说认为，暂停通过抑制抗- 炎症基因表达。我们进一步提出Pol II的遗传和药理学操作 暂停将产生重要的见解炎症性疾病的发病机制，如RA，与潜在的 to be translated翻译into advances进步in patient病人care护理.我们的具体目标是：1。仔细分析停顿的作用- MΦ中炎性基因诱导的释放检查点; 2.评估早期伸长和高阶 作为GR靶点的MΦ中的染色质相互作用; 3.评估体内操纵伸长控制的效用 使用炎症性关节炎模型。该项目的成功完成将：i）揭示 Pol II暂停炎性MΦ激活; ii）帮助完善GC的抗炎作用; iii）揭示 针对RA临床前模型中早期延伸检查点的新治疗策略的潜力。