The Role of NEMO Ubiquitination in EDA-ID

NEMO 泛素化在 EDA-ID 中的作用

• 批准号: 8227941
• 负责人: Derek W Abbott
• 金额: $ 19.63万
• 依托单位: CASE WESTERN RESERVE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-02-11 至 2014-01-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8227941
• 关键词: Acetylation; Amides; Applications Grants; Area; B-Lymphocytes; Bacterial Infections; Binding; Binding Proteins; Biochemical; Biochemistry; Bloch Sulzberger syndrome; CD4 Positive T Lymphocytes; Cells; Characteristics; Circular Dichroism; Clinical Pathways; Co-Immunoprecipitations; Coiled-Coil Domain; Communicable Diseases; Crohn' s disease; Disease; Disease susceptibility; Dissociation; Distant; Ectodermal Dysplasia; Event; Female; Gene Activation; Gene Expression; Genes; Genetic; Genetic Predisposition to Disease; Gram-Positive Bacterial Infections; Grant; Helper-Inducer T-Lymphocyte; Heterozygote; Immune; Immunologic Deficiency Syndromes; Immunologics; Infection; Inflammatory; Lead; Link; Location; Lysine; Manuscripts; Missense Mutation; Mus; Mutate; Mutation; NF-kappa B; NFKB Signaling Pathway; Organism; Pathology; Pathway interactions; Patients; Peptides; Phenocopy; Phenotype; Play; Point Mutation; Polyubiquitin; Polyubiquitination; Predisposition; Process; Proteins; Receptor Activation; Role; Signal Pathway; Signal Transduction; Signal Transduction Pathway; Site; Skin Abnormalities; Specificity; Stimulus; Structure; Surface; System; T-Lymphocyte; Testing; Toll-like receptors; Transduction Gene; Translating; Ubiquitin; Ubiquitination; Work; X Chromosome; X Inactivation; cell type; in vivo; in vivo Model; macrophage; male; mouse model; mutant; novel; public health relevance; reconstitution; response; skeletal abnormality

DESCRIPTION (provided by applicant): NF-kB signaling lies at the center of Immunodeficiency and Inflammatory diseases. A key regulator of NF-kB signal transduction, NEMO, has recently been found to be mutated in an Immunodeficiency Disorder called called Anhidrotic (hypohydrotic) Ectodermal Dysplasia with Immunodeficiency (EDA-ID). Patients with EDA-ID are susceptible to infection with gram-positive organisms, and molecularly, a dysfunctional NF-kB signaling pathway, owing to hypomorphic mutations in nemo is to blame. While the NF-kB pathway is so well-studied that it has become a paradigm for inflammatory signal transduction, this paradigm has shifted in recent years with the recognition that this pathways signal transduction strength and coordination is critically dependent on Lysine-63 (K63)-linked polyubiquitination. NEMO was very recently shown to contain a ubiquitin binding domain that is essential for NF:B signaling, and NEMO, itself, is K63-polyubiquitinated on two sites in response to innate immune stimulation (NOD2 (Crohn's Disease-susceptibility protein) and Toll-like Receptor (TLR) activation). This NEMO ubiquitination is necessary for optimal NF:B signaling (1, 2, 6, 13, 26). The spectrum and location of point mutations of nemo in EDA-ID suggest that biochemically, they may be interfering with ubiquitin binding by NEMO and/or K63-linked polyubiquitination of NEMO in response to innate immune stimuli. In addition, the varied immunologic phenotypes and immunodeficiencies in EDA-ID suggest cell-type specificity in regards to the particular mutations. Lastly, it has been difficult for the field to uncouple ubiquitin binding by NEMO from K63-linked polyubiquitination of NEMO as it relates to function and ultimately, NF:B-induced gene expression. All these difficulties point to the need to systematically evaluate EDA-ID- associated NEMO mutations in regards to ubiquitin binding, K63-linked polyubiquitination of NEMO and NF-kB-associated gene expression. These difficulties also point to a need for an in vivo model of defective NEMO ubiquitination to decipher its role in in vivo NF:B-dependent gene expression and inflammatory and immunodeficiency disorders. The grant application aims to answer these key questions. PUBLIC HEALTH RELEVANCE: The ability to determine the genetics of susceptibility to infectious disease has led to the identification of novel forms of immunodeficiency, and the challenge is to translate these genetic findings into biochemical mechanisms of disease to both better understand the disease and allow better treatment for that disease. NEMO, a protein that is central to the major inflammatory signaling pathway is mutated in a disease called EDA-ID, a disease that is characterized by susceptibility to bacterial infections. This grant aims to determine how NEMO is faulty in EDA-ID and to generate a mouse model that might mimic many of the features of EDA-ID in hopes that this might lead to a better understanding of and better treatments for this disease.

描述（由申请人提供）：NF-kB 信号传导是免疫缺陷和炎症疾病的核心。最近发现 NF-kB 信号转导的关键调节因子 NEMO 在一种称为无汗性（缺水性）免疫缺陷性外胚层发育不良（EDA-ID）的免疫缺陷性疾病中发生突变。 EDA-ID 患者容易受到革兰氏阳性菌感染，从分子角度来说，归咎于 nemo 亚等位性突变导致的 NF-kB 信号通路功能失调。虽然 NF-kB 通路经过充分研究，已成为炎症信号转导的范例，但近年来，随着人们认识到该通路的信号转导强度和协调严重依赖于赖氨酸 63 (K63) 连接的多聚泛素化，这种范例已经发生了转变。最近发现 NEMO 含有一个对 NF:B 信号转导至关重要的泛素结合域，并且 NEMO 本身在两个位点上被 K63 多泛素化，以响应先天免疫刺激（NOD2（克罗恩病易感蛋白）和 Toll 样受体 (TLR) 激活）。这种 NEMO 泛素化对于最佳 NF:B 信号传导是必需的 (1,2,6,13,26)。 EDA-ID 中 Nemo 点突变的谱和位置表明，从生化角度来看，它们可能会干扰 NEMO 与泛素的结合和/或 NEMO 响应先天免疫刺激的 K63 连接的多泛素化。此外，EDA-ID 中不同的免疫表型和免疫缺陷表明特定突变的细胞类型特异性。最后，该领域很难将 NEMO 的泛素结合与 NEMO 的 K63 连接的多泛素化分开，因为它与功能以及最终与 NF:B 诱导的基因表达有关。所有这些困难都表明需要系统地评估 EDA-ID 相关的 NEMO 突变的泛素结合、NEMO 的 K63 多泛素化和 NF-kB 相关基因表达。这些困难还表明需要有缺陷的 NEMO 泛素化体内模型来破译其在体内 NF:B 依赖性基因表达以及炎症和免疫缺陷性疾病中的作用。拨款申请旨在回答这些关键问题。 公共卫生相关性：确定传染病易感性遗传学的能力导致了新型免疫缺陷形式的鉴定，挑战是将这些遗传学发现转化为疾病的生化机制，以便更好地了解该疾病并更好地治疗该疾病。 NEMO 是一种主要炎症信号传导通路的核心蛋白，它在一种名为 EDA-ID 的疾病中发生突变，这种疾病的特点是易受细菌感染。这笔资助的目的是确定 NEMO 在 EDA-ID 中的缺陷，并生成一个可以模仿 EDA-ID 的许多特征的小鼠模型，希望这可以帮助人们更好地了解这种疾病并提供更好的治疗方法。