Novel Functions of PYRIN proteins

PYRIN 蛋白的新功能

• 批准号: 7022465
• 负责人: Christian Stehlik
• 金额: $ 7.33万
• 依托单位: WEST VIRGINIA UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2006
• 资助国家: 美国
• 起止时间: 2006-02-01 至 2008-01-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7022465
• 关键词: JUN kinase; apoptosis; cell migration; cellular immunity; enzyme activity; enzyme induction /repression; macrophage; protein protein interaction; protein structure function; tissue /cell culture

DESCRIPTION (provided by applicant): The goal of this proposal is to study the function of PYRIN domain containing proteins in innate immune responses following pathogen infection. Several pathogen recognition receptors are composed of a PYRIN domain, a central nucleotide binding NACHT domain and a leucine rich region. While the leucine rich region functions as pathogen receptor, the PYRIN domain recruits PYRIN domain containing adaptor proteins, such as ASC. Recruitment of ASC links pathogen recognition to the activation of downstream effector pathways of the innate immune system. Known effectors include activation of caspase-1 and NF-?B, as well as induction of MHC class 1 expression, which is crucial for host cell defense. Impaired regulation of this pathway is also linked to several autoinflammatory disorders. Our preliminary results suggest that signals transmitted by the PYRIN domain are not limited to these effectors, but can also activate stress-induced signal transduction pathways, which may support pathogen clearance. In particular we found that expression of the central adaptor protein ASC which contains a PYRIN domain and links signals from pathogen recognition receptors to downstream effector pathways, can induce Jun-N-terminal kinase (JNK) activation and subsequently promotes cell migration. We propose to employ THP-1 monocytes that can be differentiated into adherent macrophages and analyze PYRIN domain mediated signaling pathways. PYRIN domain signaling will be induced by employing defined ligands for the PYRIN domain containing pathogen recognition receptors. We generated ASC expressing stable THP-1 cell lines that mimic pro-inflammatory mediator-induced upregulation of the ASC protein. Cell lines with silenced ASC expression will help to associate downstream signalling events specifically with the PYRIN domain mediated signal transduction pathway. This proposal seeks to define a novel signal transduction pathway of PYRIN domain containing proteins, which is relevant for pathogen recognition and innate immune regulation. This research is also significant for several autoinflammatory disorders that are linked to hereditary mutations in genes encoding PYRIN domain containing pathogen recognition receptors. The here proposed work extends our long-term goal to define the mechanisms that link pathogen recognition to the innate immune response.

描述（由申请人提供）：该提案的目的是研究病原体感染后先天免疫反应中含有蛋白质的吡啶结构域的功能。几种病原体识别受体由吡啶结构域，中央核苷酸结合结构域和富含亮氨酸的区域组成。虽然富含亮氨酸的区域充当病原体受体，但吡啶结构域募集了含有衔接蛋白（例如ASC）的吡啶结构域。 ASC的募集募集病原体识别与先天免疫系统下游效应途径的激活。已知的效应子包括激活caspase-1和nf-？b，以及MHC 1类表达的诱导，这对于宿主细胞防御至关重要。该途径的调节受损也与几种自发性疾病有关。我们的初步结果表明，吡啶结构域传输的信号不限于这些效应子，而是可以激活应力诱导的信号转导途径，这可能支持病原体清除率。特别是我们发现，中央衔接蛋白ASC的表达包含一个吡啶结构域，并将从病原体识别受体与下游效应途径的信号联系起来，可以诱导Jun-N-末端激酶（JNK）激活，然后促进细胞迁移。我们建议采用可以区分粘附巨噬细胞的THP-1单核细胞，并分析吡啶结构域介导的信号传导途径。吡啶结构域信号传导将通过使用含有病原体识别受体的吡啶结构域的定义配体来诱导。我们产生了ASC表达稳定的THP-1细胞系，模仿了促炎性介质引起的ASC蛋白上调。具有沉默的ASC表达的细胞系将有助于将下游信号事件与吡啶结构域介导的信号转导途径相关联。该提案旨在定义含有蛋白质的吡啶结构域的新型信号转导途径，这与病原体识别和先天免疫调节有关。这项研究对于几种与编码含有病原体识别受体的pyrin结构域的遗传突变相关的几种自身炎症性疾病也很重要。这里提出的工作扩展了我们的长期目标，以定义将病原体识别与先天免疫反应联系起来的机制。