Molecular Bases of Inflammasome Regulation Mediated by ASC Isoforms

ASC 异构体​​介导的炎症小体调节的分子基础

• 批准号: 9810959
• 负责人: Eva de Alba Bastarrechea
• 金额: $ 44.34万
• 依托单位: UNIVERSITY OF CALIFORNIA, MERCED
• 依托单位国家: 美国
• 财政年份: 2019
• 资助国家: 美国
• 起止时间: 2019-06-01 至 2023-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9810959
• 关键词: Adaptor Signaling Protein; Address; Adopted; Adult Respiratory Distress Syndrome; Affect; Amino Acid Sequence; Amino Acids; Atherosclerosis; Autoimmune Diseases; Behavior; Binding; CASP1 gene; Cardiovascular Diseases; Cells; Characteristics; Chemicals; Chronic; Complement; Complex; Cone; Cytokine Activation; Data; Death Domain; Disease; Engineering; Enzyme-Linked Immunosorbent Assay; Fluorescence Anisotropy; Fluorescence Spectroscopy; Glues; Goals; Grant; Homo; Immune; In Vitro; Infection; Inflammasome; Inflammation; Inflammatory; Inflammatory Response; Injury; Innate Immune Response; Innate Immune System; Interleukin-18; Interleukins; Kinetics; Knowledge; Length; Life; Macromolecular Complexes; Mediating; Mental Depression; Mission; Modeling; Molecular; Molecular Conformation; Molecular Sieve Chromatography; Molecular Structure; Monitor; Motion; Movement; Multiprotein Complexes; Natural Immunity; Nuclear Magnetic Resonance; Nuclear Structure; Peptides; Play; Property; Protein Isoforms; Proteins; Publishing; Regulation; Relaxation; Relaxation Techniques; Resolution; Rheumatoid Arthritis; Role; Signal Transduction; Site; Spectrometry, Mass, Electrospray Ionization; Structure; Testing; Time; Tissues; Transmission Electron Microscopy; United States National Institutes of Health; Vertebral column; base; cancer type; cytokine; design; experience; experimental study; fighting; flexibility; human disease; innovation; nervous system disorder; organizational structure; pathogen; protein complex; protein function; recruit; self assembly; sensor; stoichiometry; therapeutic development; therapeutic target

PROJECT SUMMARY/ABSTRACT. Inflammation is our primary response from the innate immune system to fight infection and self-protect from damage. However, dysfunctional regulation of inflammation results in disease, including certain types of cancer, autoimmune, cardiovascular and neurological disorders, rheumatoid arthritis, and even depression. The onset of inflammation depends on the assembly of a multiprotein complex known as the inflammasome. The main players in inflammasome assembly are; - sensor proteins that react upon danger signals derived from pathogens or damaged tissue; - procaspase-1 that activates inflammatory cytokines as a result of inflammasome assembly; - the adapter ASC that functions like a molecular glue by connecting sensor and procaspase-1 molecules. Canonical ASC has an isoform, which shows different self-assembly capabilities and modulates the intensity of inflammation in the cellular context. The presence of protein isoforms is a well-known, natural mechanism for the regulation of protein function. Both proteins are bimodular with two Death Domains connected by a linker, and their amino acid sequences differ solely in the linker length. Canonical ASC has a 23 amino acid-long linker, whereas its isoform has a shorter linker of 3 amino acids (ASC_short). We demonstrated that ASC linker plays a key role in defining the orientation of its domains, and show in this proposal that both domains actively participate in ASC self-assembly to form filamentous macrostructures. Evidence indicate that inflammasomes assemble into different supramolecular structures. However, little is known on the factors controlling these structural arrangements, or how the different assemblies impact inflammation. This proposal aims at addressing a knowledge gap in the role of ASC isoforms on inflammasome structural organization and inflammatory response. The long-term goal of this proposal is to gain in-depth knowledge on the interplay between the inflammasome components to understand its function and regulation, which is of great significance to set the grounds for the development of therapeutics to control inflammation. The objective of this grant is innovative because it will decipher the unknown molecular bases for inflammasome regulation mediated by ASC isoforms. Our hypothesis is that; 1) the linker length has important implications in the interaction properties of ASC and ASC_short at the molecular level, which can account for the observed alteration of the inflammatory response, 2) the linker length leads to differences in the interdomain dynamics of the two isoforms and in the resulting macrostructures. To test this hypothesis we propose to; 1) determine the inflammatory activity, precise self-association and interacting capabilities of ASC isoforms, including ASC, ASC_short and an artificial form of ASC engineered with a long linker (3 times the canonical linker length: ASC_long) as a reference for independent domains, 2) determine the interdomain dynamics of the three isoforms using Nuclear Magnetic Resonance; 3) discern with Transmission Electron Microscopy the potentially different characteristics of the macrostructures resulting from ASC isoforms self-association, and their implication in inflammatory activity.

项目摘要/摘要。炎症是我们先天免疫系统对 与损害抗击感染和自我保护。但是，炎症功能失调导致 疾病，包括某些类型的癌症，自身免疫性，心血管和神经系统疾病，类风湿病 关节炎，甚至抑郁症。炎症的发作取决于多蛋白复合物的组装 被称为炎性体。炎症大会的主要参与者是； - 反应的传感器蛋白 来自病原体或组织受损的危险信号； - 激活炎症细胞因子的procaspase-1 由于炎症体组装的结果； - 通过连接的适配器ASC像分子胶一样起作用 传感器和procaspase-1分子。 Canonical ASC具有同工型，显示出不同的自组装 能力并调节细胞环境中炎症的强度。蛋白质同工型的存在 是一种众所周知的自然机制，用于调节蛋白质功能。两种蛋白质都是双相的，有两个 通过接头连接的死亡域，其氨基酸序列仅在接头长度上有所不同。典范 ASC具有23个氨基酸长的连接器，而其同工型具有3个氨基酸（ASC_SHORT）的较短连接器。我们 证明ASC接头在定义其域的方向方面起着关键作用，并在此提案中显示 这两个领域都积极参与ASC组装以形成丝状宏观结构。证据 表明炎性症组合成不同的超分子结构。但是，在 控制这些结构排列的因素，或不同的组件如何影响炎症。这 提案旨在解决ASC同工型在炎性体结构中的作用的知识差距 组织和炎症反应。该提议的长期目标是获得深入的知识 炎性组组件之间的相互作用以了解其功能和调节，这是很棒的 为发展炎症的疗法开发奠定理由的意义。这个目的 授予具有创新性，因为它将破译炎症体调节的未知分子碱基 通过ASC亚型。我们的假设是； 1）接头长度在交互中具有重要意义 ASC和ASC_SHORT在分子水平上的特性，这可以解释观察到的改变 炎症反应，2）接头长度会导致两种同工型的域间动力学差异 并在由此产生的宏观结构中。为了检验这一假设，我们提出了； 1）确定炎症 ASC同工型的活动，精确的自我关联和相互作用的功能，包括ASC，ASC_SHORT和A 用长链接器（规范接头长度：ASC_LONG）进行的ASC的人工形式作为参考 对于独立域，2）使用核磁性确定三种同工型的域间动力学 谐振; 3）与透射电子显微镜辨别潜在的不同特征 ASC同工型自我关联产生的宏观结构及其在炎症活性中的影响。