Molecular Mechanism of the NFkappaB Essential Modulator (NEMO) Scaffold Protein Mutated in Human Immunodeficiencies

项目摘要/摘要 信号转导通路在正常的细胞生理和变化中起着普遍而重要的作用 在这些途径中发现了许多人类疾病。许多信号转导研究不足的一个方面 通路是支架蛋白的作用，支架蛋白充当信号蛋白的整合平台。核因子-κB 在许多炎症性和免疫性疾病和癌症中，信号通路被改变，因此被认为是 治疗干预的目标。项目的总体目标是提高我们对信令的理解 支架蛋白NF-κB Essential调制器(NEMO)是κB激酶(IKK)复合体抑制因子的组成部分， 它是核因子-κB信号转导的关键调控节点。除了尼莫在慢性疾病中扮演的角色之外 核因子-κB在人类疾病中的高活性，在几种人类免疫缺陷中发现NEMO突变 疾病。该项目的长期目标是了解像Nemo这样的支架蛋白是如何使用的 构象变化，以调节结合到的信号蛋白之间的功能相互作用 以阐明NEMO关键区域致病突变的结构基础，并鉴定 调节NEMO活性的小分子药物的新靶点。以下是具体目标 追查： 1.将使用结构、生物物理和分子方法来表征新发现的 NEMO的“介入域”(IVD；AA 111-195)，并阐明IVD在 调节IKKβ结合。此外，免疫缺陷疾病的潜在机制(S) IVD区域的突变将被确定。 2.最近发现的NEMO与IκBα之间的相互作用将用生化和 细胞方法，以确定该界面是否为治疗提供了替代靶点 干预。 3.NEMO调节I-κB被IKKβ磷酸化的机制及其在这一过程中的作用 由尼莫的构象变化所起的作用，将被评估和定义。 项目团队包括三名首席调查员，他们拥有专业知识和经验，涉及 项目，包括分析开发、定量和机械生物化学、X射线结晶学和 小角X射线散射、生物物理学、药物发现和核因子-κB途径生物学与疾病。这个 这项研究的结果将进一步加深我们对Nemo在正常细胞生理和 NEMO相关的遗传免疫缺陷，并可能导致人类新疗法的开发 疾病。

PROJECT SUMMARY/ABSTRACT Signal transduction pathways play pervasive and important roles in normal cellular physiology, and alterations in these pathways are found in many human diseases. One under-studied aspect of many signal transduction pathways is the role of scaffold proteins, which act as integrating platforms for signaling proteins. The NF-κB signaling pathway is altered in many inflammatory and immune diseases and cancers, and is thus viewed as target for therapeutic intervention. The overall project goal is to advance our understanding of the signaling scaffold protein NF-κB essential modulator (NEMO), a component of the inhibitor of κB kinase (IKK) complex, which is a key regulatory node for NF-κB signaling. In addition to NEMO playing a role in the chronic hyperactivity of NF-κB in human diseases, mutations in NEMO are found in several human immunodeficiency diseases. The long-term goals of the project are to understand how scaffolding proteins such as NEMO use conformational change to regulate the functional interactions between the signaling proteins that are bound to them, to elucidate the structural basis for disease-causing mutations in key regions of NEMO, and to identify new target sites for small molecule drugs that modulate NEMO activity. The following specific aims will be pursued: 1. Structural, biophysical and molecular approaches will be used to characterize the newly discovered “Intervening Domain” (IVD; aa 111-195) of NEMO, and to elucidate the role that the IVD plays in modulating IKKβ binding. Additionally, the mechanism(s) underlying immunodeficiency disease-causing mutations in the IVD region will be established. 2. The recently discovered interaction between NEMO and IκBα will be characterized using biochemical and cellular approaches, to establish whether this interface provides alternative target sites for therapeutic intervention. 3. The mechanism by which NEMO regulates the phosphorylation of IκB by IKKβ, and the role in this process played by a conformational change in NEMO, will be assessed and defined. The project team includes three Principal Investigators with expertise and experience across all aspects of the project, including assay development, quantitative and mechanistic biochemistry, X-ray crystallography and small-angle X-ray scattering (SAXS), biophysics, drug discovery, and NF-κB pathway biology and disease. The outcomes of this research will further our understanding of the role of NEMO in normal cellular physiology and in NEMO-related genetic immunodeficiencies, and may lead to the development of new therapeutics for human disease.