Two novel threonine phosphorylations of STAT2 impact inflammatory responses to bacterial infection.

STAT2 的两种新型苏氨酸磷酸化影响细菌感染的炎症反应。

• 批准号: 10026693
• 负责人: GEORGE ROBERT STARK
• 金额: $ 56.26万
• 依托单位: CLEVELAND CLINIC LERNER COM-CWRU
• 依托单位国家: 美国
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-08-07 至 2024-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10026693
• 关键词: Acute; Address; Affect; Antiviral Agents; Automobile Driving; Bacteria; Bacterial Infections; Bacterial Model; Biological; Biological Assay; Biological Process; Body Weight decreased; Cause of Death; Cell Culture Techniques; Cells; Chronic Disease; Colon; DNA Binding; DNA-Binding Proteins; Data; Drug Targeting; Enzyme Inhibitor Drugs; Enzymes; Functional disorder; Gene Expression; Genes; Genetic Transcription; Heart; Immune response; Impairment; Infection; Infectious Agent; Inflammation; Inflammatory; Inflammatory Response; Innate Immune Response; Intensive Care Units; Interferon Type I; Interferon Type II; Interferons; Interleukin-1; Interleukin-6; Invaded; Kidney; Kinetics; Knock-in Mouse; Laboratories; Lipopolysaccharides; Liver; Lung; Mediating; Methods; Modeling; Molecular Conformation; Mus; Mutation; Organ; Pathway interactions; Phase; Phenotype; Phosphoric Monoester Hydrolases; Phosphorylation; Phosphotransferases; Play; Proteins; RIPK2 gene; Role; STAT1 gene; STAT2 gene; Sepsis; Septic Shock; Series; Signal Transduction; Simplexvirus; Site; Sodium Dextran Sulfate; Stimulus; Structural Models; System; TNF gene; Testing; Therapeutic Agents; Threonine; Transcriptional Activation; Tyrosine; Tyrosine Phosphorylation; Ulcer; Ulcerative Colitis; Vesicular stomatitis Indiana virus; Virus; Wild Type Mouse; Work; base; chemokine; commensal bacteria; cytokine; dextran sulfate sodium induced colitis; dimer; experience; experimental study; improved; inflammatory disease of the intestine; inhibitor/antagonist; interest; intestinal barrier; intestinal injury; mortality; mouse model; novel; novel strategies; novel therapeutic intervention; pathogen; prevent; response; transcription factor

Project Summary The major transcription factor that drives responses to type I interferon (IFN-I) is ISGF3, comprised of tyrosine- phosphorylated STATs 1 and 2 and the DNA binding protein IRF9. The threonine phosphorylation of STAT2 on T387 and T404 profoundly affects the ability of IFN-I to drive gene expression and dependent biological functions. Furthermore, STAT2 lacking tyrosine phosphorylation (U-STAT2) enhances the expression of NF-κB target genes that encode several chemokines and pro-inflammatory cytokines (for example, IL-6), and also inhibits the ability of IFN-γ to activate the tyrosine phosphorylation of STAT1 and downstream gene expression. These non-canonical functions of U-STAT2 are also regulated by its phosphorylation on T387 and T404. Dramatic effects are seen with mice carrying homozygous T-A mutations at each of these two sites. The defective response to IFN-I in T403A mice causes them to be highly susceptible to infections with vesicular stomatitis virus (VSV) or Herpes Simplex virus (HSV). (The numbers for mice are T386 and T403.) The responses of T403A mice to inflammatory stimuli are also greatly compromised. Ulcerative colitis is a chronic disease in which the lining of the colon becomes inflamed and develops ulcers. In the dextran sulfate sodium (DSS)-induced model of ulcerative colitis, T403A/T403A knockin mice, in which this site cannot be phosphorylated, are very much more sensitive than WT/WT mice to DSS-induced mortality and weight loss. Sepsis and septic shock are the leading causes of death in non-coronary intensive care units. We have shown that the immune response in sepsis transitions from an early/hyper-inflammatory to a late/hypo-inflammatory, immunosuppressive phenotype that is associated with multiple organ dysfunction involving lung, heart, kidney and liver. Furthermore, prolonged hypo-inflammation is associated with impaired pathogen clearance. Compared with wild- type controls, T403A/T403A mice are protected from, and T386A/T386A mice are sensitized to challenge with lipopolysaccharide (LPS), an inducer of septic shock, and the induction of IFN-I and IL-6 expression is suppressed in T403A/T403A mice. Our primary objectives follow. 1) We want to understand in detail how the phosphorylation of STAT2 on these two threonine residues is regulated (which activating signals? which kinases? which phosphatases?). 2) We want to understand in detail how pro-inflammatory mechanisms are affected by STAT2 threonine phosphorylation. 3) We want to use this information to develop novel therapeutic approaches to inflammatory responses to commensal bacteria, especially colonic inflammation and septic shock. We anticipate that we can parlay improved understanding of the roles of threonine phosphorylation of STAT2 in inflammation and infection into novel therapeutic approaches, and that the discovery of novel approaches to ameliorate bacterially-induced acute inflammation may also be helpful in other inflammatory conditions.

项目概要 驱动对 I 型干扰素 (IFN-I) 反应的主要转录因子是 ISGF3，由酪氨酸- 磷酸化的 STAT 1 和 2 以及 DNA 结合蛋白 IRF9。 T387 上 STAT2 的苏氨酸磷酸化 T404 深刻影响 IFN-I 驱动基因表达和依赖的生物功能的能力。 此外，缺乏酪氨酸磷酸化的 STAT2 (U-STAT2) 增强 NF-κB 靶基因的表达 编码多种趋化因子和促炎细胞因子（例如 IL-6），并且还抑制 IFN-γ 激活 STAT1 的酪氨酸磷酸化和下游基因表达。这些非规范的 U-STAT2 的功能还受到其 T387 和 T404 磷酸化的调节。戏剧性的效果可见于 在这两个位点均携带纯合 T-A 突变的小鼠。 T403A 小鼠对 IFN-I 的反应缺陷 导致他们极易感染水泡性口炎病毒（VSV）或单纯疱疹病毒（HSV）。 （小鼠编号为T386和T403。）T403A小鼠对炎症刺激的反应也很大 妥协了。溃疡性结肠炎是一种慢性疾病，结肠内壁发炎并发展 溃疡。在右旋糖酐硫酸钠（DSS）诱导的溃疡性结肠炎模型中，T403A/T403A敲入小鼠，其中 该位点不能被磷酸化，比 WT/WT 小鼠对 DSS 诱导的死亡更加敏感 减肥。败血症和败血性休克是非冠心病重症监护病房中死亡的主要原因。我们有 研究表明脓毒症中的免疫反应从早期/高炎症转变为晚期/低炎症， 与肺、心、肾等多器官功能障碍相关的免疫抑制表型 肝。此外，长时间的低炎症与病原体清除受损有关。与野生相比—— 类型对照，T403A/T403A 小鼠受到保护，T386A/T386A 小鼠对攻击敏感。 脂多糖 (LPS) 是败血性休克的诱导剂，并且 IFN-I 和 IL-6 表达的诱导在 T403A/T403A 小鼠。我们的主要目标如下。 1）我们想详细了解磷酸化是如何进行的 这两个苏氨酸残基上的 STAT2 受到调节（哪个激活信号？哪个激酶？哪个 磷酸酶？）。 2）我们想详细了解STAT2如何影响促炎机制 苏氨酸磷酸化。 3）我们希望利用这些信息来开发新的治疗方法 对共生细菌的炎症反应，尤其是结肠炎症和脓毒性休克。我们 预计我们可以加深对 STAT2 苏氨酸磷酸化作用的理解 炎症和感染成为新的治疗方法，并且新方法的发现 改善细菌引起的急性炎症也可能有助于治疗其他炎症。