Elucidating the novel mechanism of importins in NLRP6 inflammasome regulation

阐明NLRP6炎症小体调节中输入蛋白的新机制

• 批准号: 10574850
• 负责人: Chen Shen
• 金额: $ 23.33万
• 依托单位: WASHINGTON UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-08-10 至 2025-07-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10574850
• 关键词: Adaptor Signaling Protein; Affect; American; Binding; Biochemical; Biochemistry; Biological Assay; Biology; CASP1 gene; Caspase; Cell Death; Cell Nucleus; Cell physiology; Cells; Cellular biology; Chronic Disease; Co-Immunoprecipitations; Colon; Complex; Crohn' s disease; Cryoelectron Microscopy; Cytosol; Disease; Double-Stranded RNA; Drug Targeting; Event; Gastrointestinal tract structure; Homeostasis; Host Defense; Hyperactivity; IL18 gene; Image; Immune; Importins; In Vitro; Inflammasome; Inflammation; Inflammatory; Inflammatory Bowel Diseases; Injury; Interferons; Interleukins; Intestines; Leucine-Rich Repeat; Light; Link; Liquid substance; Liver; Mass Spectrum Analysis; Mediating; Molecular; Molecular Machines; Monitor; Mus; Mutation; Nuclear Import; Nuclear Translocation; Nucleotides; Outcome; Phase; Plants; Play; Polymers; Process; Production; Protein Family; Proteins; Publishing; RNA-Binding Proteins; Regulation; Reporting; Role; Signal Induction; Signal Transduction; Signaling Protein; Structure; Syndrome; Testing; Therapeutic Intervention; Tissues; Ulcerative Colitis; VDAC1 gene; Viral; Virus; Virus Diseases; Western Blotting; autoinflammatory; chronic inflammatory disease; cytokine; dextran sulfate sodium induced colitis; experimental study; in vivo; insight; meter; mutant; novel; nucleocytoplasmic transport; pathogen; polymerization; prevent; receptor; recruit; response; scaffold; sensor; targeted treatment; tissue injury; tool; transcription factor; transport inhibitor

Abstract Inflammasomes are multi-protein signaling scaffolds that form in the cytosol upon stimulation by pathogen and damage signals to activate caspase-1. Canonical inflammasome sensors are mainly nucleotide-binding domain (NBD) and leucine-rich repeat containing (NLR) proteins, such as NLRP1, NLRP3 and NLRP6. Once inflammasome is activated, caspase-1 is recruited to the platform and activated through proximity-induced autoproteolysis. Activated caspase-1 processes pro-interleukin (IL)-1b, pro-IL-18, and the pore-forming protein gasdermin D (GSDMD), resulting in the maturation and release of these cytokines, as well as pyroptotic cell death. NLRP6 plays versatile roles in host defense. It is highly expressed in the intestine and the liver. The inflammasome function of NLRP6 has been reported to protect the host from pathogen evasion and injury-induced tissue damage. On the other hand, the excessive NLRP6 inflammasome activation and the subsequent hyperactive IL-18 signaling may exacerbate the tissue damage and cause chronic inflammatory diseases such as inflammatory bowel disease (IBD). Whether there is an intrinsic cellular signal that tunes the activity of NLRP6 inflammasome becomes an intriguing question. The question is critical to understanding how our body maintains tissue homeostasis by harnessing this important inflammasome and to provide targeted therapy for certain diseases. Nuclear import is an essential cellular process in innate immune defense by translocating activated transcription factors into the nucleus for interferon production. Plant NLRs themselves have been reported to enable host defense through pathogen effector-mediated nuclear translocation. In our preliminary study, we found that importin-b1, a common nuclear import receptor, inhibits dsRNA-induced liquid-liquid phase separation of NLRP6 in-vitro, which implicates the potential link between nuclear import and NLRP6 inflammasome signaling. In this application, we will investigate the potential role of importins in regulating the NLRP6 inflammasome by tackling two questions: 1) molecular basis of the importin-NLRP6 interaction (cryo-electron microscopy and biochemistry), and 2) the roles of importin-b1 in negatively regulating NLRP6 inflammasome upon viral infection (inflammasome cell biology).

抽象的 炎性症是在刺激时在细胞质中形成的多蛋白信号传导支架 病原体和损伤信号激活caspase-1。规范性炎症传感器是 主要是核苷酸结合结构域（NBD）和富含亮氨酸的重复（NLR）蛋白，这种蛋白 作为NLRP1，NLRP3和NLRP6。一旦激活了炎性体，caspase-1就会招募到 平台并通过接近性诱导的自动蛋白酶解析而激活。激活的caspase-1过程 Pro-Interleukin（IL）-1B，Pro-IL-18和孔形成蛋白质加油机D（GSDMD），由此产生 在这些细胞因子以及凋亡细胞死亡的成熟和释放中。 NLRP6播放 在主持人防御中的多功能角色。它在肠和肝脏中高度表达。这 据报道，NLRP6的炎性体功能可保护宿主免受病原体的逃避 和受伤引起的组织损伤。另一方面，过多的NLRP6发炎 激活和随后的多动性IL-18信号传导可能会加剧组织损伤 并引起慢性炎症性疾病，例如炎症性肠病（IBD）。无论 有一个内在的细胞信号调节NLRP6炎性体的活性变成 有趣的问题。问题对于了解我们的身体如何维持组织至关重要 通过利用这种重要的炎症体并提供针对性的治疗，以实现稳态 某些疾病。 核进口是通过易位的先天免疫防御的重要细胞过程 活化的转录因子进入核中以产生干扰素。植物本身 据报道，通过病原体效应介导的核能使宿主防御 易位。在我们的初步研究中，我们发现Importin-B1是一种常见的核进口 受体，抑制dsRNA诱导的NLRP6液相分离，即 暗示核进口与NLRP6炎症体信号传导之间的潜在联系。 在此应用中，我们将研究进口素在调节NLRP6中的潜在作用 通过解决两个问题的炎症组：1）importin-nlrp6相互作用的分子基础 （冷冻电子显微镜和生物化学），以及2）importin-b1在负面 调节病毒感染后的NLRP6炎症体（炎症体细胞生物学）。