Regulation and Function of MEKK3 in Dendritic Cells

MEKK3在树突状细胞中的调控和功能

• 批准号: 7196525
• 负责人: BING SU
• 金额: $ 38.45万
• 依托单位: YALE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2005
• 资助国家: 美国
• 起止时间: 2005-06-01 至 2010-02-28
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7196525
• 关键词: Antigen-Presenting Cells; Appendix; Arthritis; Atherosclerosis; Autoimmunity; B-Lymphocytes; Bone Marrow; Cell Differentiation process; Cell Lineage; Cell Maturation; Cell physiology; Cells; Cellular biology; Complex; Dendritic Cells; Dendritic cell activation; Development; Disease; Doctor of Philosophy; Embryo; Family; Gene Expression; Gene Family; Genes; Germ Lines; Goals; Hematopoietic stem cells; Homologous Gene; IKK alpha; Immune; Immune response; Immune system; Immunity; Immunologic Receptors; Infection; Inflammatory; Interleukin-1; Interleukin-1 Receptors; Knock-out; Knockout Mice; Lead; MAP Kinase Kinase Kinase; Malignant Neoplasms; Mediating; Mitogen-Activated Protein Kinases; Molecular; Molecular Target; Mus; NF-kappa B; Natural Immunity; Nuclear; Outcome Study; Pathologic Processes; Pathway interactions; Pattern; Phosphorylation; Phosphotransferases; Physiological; Play; Process; Protein-Serine-Threonine Kinases; Proteins; Receptor Signaling; Regulation; Research Design; Research Personnel; Resources; Role; Sepsis; Series; Signal Pathway; Signal Transduction; Signaling Molecule; Small Interfering RNA; Specificity; TNF receptor-associated factor 6; TRAF6 gene; Testing; Therapeutic Intervention; Toll-Like Receptor Family Gene; Toll-Like Receptor Pathway; Toll-like receptors; Transducers; Tumor Necrosis Factor Receptor; base; cytokine; homologous recombination; hybrid protein; in vivo; microorganism; mutant; novel; prevent; programs; toll-like receptor 4

DESCRIPTION (provided by applicant): Toll-like receptors (TLRs) play a central role in innate and adaptive immunity. TLRs have evolved to detect infection by recognizing the conserved molecular patterns of microorganisms, and such recognition leads to the induction of innate and adaptive immunity through the activation and maturation of dendritic cells (DCs), the most potent professional antigen-presenting cells (APCs). The central question regarding the induction of both innate and adaptive immune responses is how the immune receptor-mediated signals are transduced intracellularly, thereby leading to the nuclear gene expression and immune effector functions. The mitogen-activated protein kinase (MAPK) and the IkappaBalpha kinase (IKK) are the main targets of the TLR pathways in DCs and other cells in immune system. MEKK3 is a serine/threonine protein kinase that belongs to the MAPK kinase kinase family. We disrupted the Mekk3 gene in mice and found that MEKK3 is a key signal transducer of the IL-1R and TLR4 signaling to the downstream MAPK and IKK pathways. Because the IL-1 receptor (IL-1R)/TLR gene family is central for the multiple aspects of DC biology, we hypothesize that MEKK3 plays an essential role in DC function. The proposed studies are designed to elucidate the molecular mechanisms of MEKK3 signaling and MEKK3 function in DCs through the IL-1R-TLR pathways. Four Specific Aims are proposed: (1) to define the molecular mechanism of MEKK3 activation by IL-1R-TLR4. (2) to determine the structural basis of MEKK3 specificity in the IL-1R-TLR4 pathways and to isolate and clone MEKK3 regulators and targets in DCs. (3) to determine the role of MEKK3 in DC activation and maturation. (4) to investigate the role of MEKK3 in DC differentiation in vivo. We will determine MEKK3 intracellular localization, phosphorylation, enzymatic activity, and MEKK3 association with adaptor molecules in the IL-1R-TLR pathways. We will determine the MEKK3 functional domains and clone MEKK3 regulators in DCs. We will establish MEKK3-deficient DCs using Mekk3-/- embryos, Mekk3 siRNA, and Mekk3 floxed mice and determine the role of MEKK3 in MAPK and IKK-NF-kappaB activation, and in DC lineage differentiation, activation and maturation. In addition to revealing the regulation and function of MEKK3 in DCs, the outcome from this study will also provide conceptual and material resources for studying MEKK3 and its homologues in many other physiological and pathological processes. Most importantly, this study may discover novel molecular targets for therapeutic interventions for treating diseases such as arthritis, sepsis, atherosclerosis, autoimmunity, and cancer.

描述（由申请人提供）：Toll样受体（TLR）在先天性和适应性免疫中发挥核心作用。TLR已经进化为通过识别微生物的保守分子模式来检测感染，并且这种识别通过树突状细胞（DC）（最有效的专职抗原呈递细胞（APC））的激活和成熟来诱导先天性和适应性免疫。关于先天性和适应性免疫应答的诱导的中心问题是免疫受体介导的信号如何在细胞内转导，从而导致核基因表达和免疫效应器功能。丝裂原活化蛋白激酶（mitogen-activated protein kinase，MAPK）和IkappaB α激酶（IKK）是树突状细胞（DCs）等免疫系统细胞TLR通路的主要靶点。MEKK 3是属于MAPK激酶激酶家族的丝氨酸/苏氨酸蛋白激酶。我们在小鼠中破坏Mekk 3基因，发现MEKK 3是IL-1 R和TLR 4信号传导至下游MAPK和IKK通路的关键信号转导子。由于IL-1受体（IL-1 R）/TLR基因家族是DC生物学多个方面的核心，我们假设MEKK 3在DC功能中起着重要作用。本研究旨在通过IL-1 R-TLR通路阐明MEKK 3信号转导和MEKK 3在DC中的功能的分子机制。本研究的主要目的是：（1）阐明IL-1 R-TLR 4激活MEKK 3的分子机制。(2)确定MEKK 3在IL-1 R-TLR 4通路中特异性的结构基础，并分离和克隆DC中的MEKK 3调节剂和靶标。(3)以确定MEKK 3在DC活化和成熟中的作用。(4)研究MEKK 3在体内DC分化中的作用。我们将确定MEKK 3的细胞内定位，磷酸化，酶活性，以及MEKK 3与IL-1 R-TLR途径中的衔接分子的关联。我们将确定MEKK 3的功能结构域和克隆MEKK 3调节剂在DC中。我们将使用Mekk 3-/-胚胎、Mekk 3 siRNA和Mekk 3 floxed小鼠建立MEKK 3缺陷型DC，并确定MEKK 3在MAPK和IKK-NF-kappaB活化以及DC谱系分化、活化和成熟中的作用。除了揭示MEKK 3在DC中的调节和功能外，本研究的结果还将为MEKK 3及其同源物在许多其他生理和病理过程中的研究提供概念和材料资源。最重要的是，这项研究可能会发现新的分子靶点，用于治疗关节炎，脓毒症，动脉粥样硬化，自身免疫和癌症等疾病的治疗干预。