IRE1beta: A Novel Pathway for Regulation of Airway Epithelial Mucin Production

IRE1beta：调节气道上皮粘蛋白产生的新途径

基本信息

批准号：
8089547
负责人：
Carla Maria Pedrosa Ribeiro
金额：
$ 18.5万
依托单位：
UNIV OF NORTH CAROLINA CHAPEL HILL
依托单位国家：
美国
项目类别：
财政年份：
2010
资助国家：
美国
起止时间：
2010-07-01 至 2013-06-30
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/8089547
关键词：
Address Asthma Binding Proteins Boxing Bronchi Cells Characteristics Chronic Bronchitis Chronic Obstructive Airway Disease Clara cell Clara cell-specific protein Couples Cystic Fibrosis Dehydration Disease Endoplasmic Reticulum Enzymes Epithelial Exhibits Exposure to Factor X Genes Genetic Transcription Human In Vitro Inflammation Inflammatory Inositol Interleukin-13 Knock-out Lead Link MAP Kinase Gene MAPK14 gene MAPK8 gene MUC5B gene Mediating Messenger RNA Metaplasia Modeling Mucins Mucous body substance Mus Nasopharynx Obstruction Ovalbumin Pathogenesis Pathway interactions Production Protein Isoforms Protein Secretion Proteins Pseudomonas aeruginosa Regulation Relative (related person)Role Signal Pathway Signal Transduction Specificity Stimulus Structure of parenchyma of lung Structure of respiratory epithelium Testing Time Tissues Trachea Tracheal Epithelium Wild Type Mouse activating transcription factor airway epithelium airway inflammation alveolar type II cell base biological adaptation to stress bronchial epithelium cystic fibrosis airway cystic fibrosis patients cytokine endoplasmic reticulum stress epithelial Na+ channel gastrointestinal epithelium glycosylation in vitro Model in vitro testing in vivo in vivo Model knock-down mitogen-activated protein kinase p38 mouse model novel public health relevance respiratory response therapeutic target

项目摘要

DESCRIPTION (provided by applicant): Airway inflammatory diseases such as asthma, chronic obstructive pulmonary disease (COPD) and cystic fibrosis (CF) are characterized by mucous cell metaplasia and mucus overproduction. This application addresses a central issue in the pathogenesis of these diseases by investigating a novel mechanism responsible for the overproduction of mucins during airway inflammation. Inflammation of human bronchial epithelia (HBE) activates the unfolded protein response (UPR). The UPR activation couples to stimulation of the inositol requiring enzyme 1 (IRE1), an ER enzyme that activates the transcription factor X-box binding protein 1 (XBP-1), the canonical IRE1-dependent pathway required for protein secretion in many cells. Although recent studies have shown that activation of the IRE1/XBP-1 pathway is functionally relevant for airway epithelial inflammation-mediated cytokine secretion in vitro and in vivo, the role of IRE1 signaling in mucin production during airway inflammation has not been investigated. Because IRE1 can also activate JNK and p38 MAP kinases and NF-?B (non-canonical IRE1 pathways), and their activation can induce mucin transcription, IRE1 might also be functionally relevant for mucin production. IRE1 exists in two isoforms, 1 and 2. We found that IRE1a was ubiquitously expressed, but IRE1¿ was present only in gut and respiratory epithelia. While IRE1¿ expression was > 30 fold higher than IRE1a expression in HBE, IRE1¿ was absent in primary human alveolar type II cells. Moreover, a strong correlation between IRE1¿2 and MUC5B expression was found during HBE differentiation. In mouse tissues, IRE1¿ was absent in lung parenchyma but its expression was 6.5-8.5 fold higher than IRE1a expression in nasopharynx, trachea, and bronchus, tissues that exhibit higher levels of mucous cells. In wild-type (wt) mice, IRE1¿ was expressed in Clara cells and ovalbumin (OVA)-induced mucous cells, but was absent in ciliated cells, suggesting a specific function for IRE1¿ related to mucin production. OVA-increased airway epithelial Muc5b and Muc16 production was blunted in IRE1¿-/- vs. wt mice. Further evidence for a key functional role of IRE1¿ in mucin production was given by a strong correlation between IRE1¿ and genes involved in mucin production or glycosylation. Our Specific Aims will test the primary hypothesis that IRE1¿ is required for mucin production by airway mucous cells, it stimulates mucin transcription and/or regulates genes involved in mucin production or glycosylation, its action is distinct from IRE1a action, and knocking out IRE1¿ will reduce mucin overproduction in models relevant for human airways inflammatory disease. Studies will utilize in vitro and in vivo models of airway inflammation characterized by mucous cell metaplasia and mucin overproduction. Primary cultures of wt and IRE1¿-/- murine airway epithelia, primary cultures of HBE expressing different levels of IRE1¿, and the Scnn1b mouse exhibiting deletion of IRE1¿ in airway epithelia will be used to test the role of IRE1¿ in mucin production. These novel studies may have a high impact by revealing IRE1¿ as a therapeutic target for asthma, COPD, and CF airways disease. PUBLIC HEALTH RELEVANCE: Mucin overproduction characterizes many airway inflammatory diseases. Our studies will test the functional role of IRE1¿, a protein involved in endoplasmic reticulum stress responses, in mucin production associated with airway inflammation and may lead to new therapies for asthma, COPD and CF patients.

描述（由应用提供）：气道炎症性疾病，例如哮喘，慢性阻塞性肺疾病（COPD）和囊性纤维化（CF），其特征是粘液细胞化生和粘膜过量产生。该应用程序通过研究导致气道炎症期间粘蛋白过量生产的新机制来解决这些疾病发病机理的核心问题。人支气管上皮（HBE）的炎症激活了展开的蛋白质反应（UPR）。 UPR激活夫妇刺激需要酶1（IRE1）的肌醇，这是一种激活转录因子X-box结合蛋白1（XBP-1）的ER酶，这是许多细胞中蛋白质分泌所需的典型IRE1依赖性途径。尽管最近的研究表明，IRE1/XBP-1途径的激活在功能上与气道上皮炎症介导的体外和体内细胞因子分泌有关，但尚未研究IRE1信号在粘蛋白注射过程中的粘蛋白产生中的作用。因为IRE1还可以激活JNK和p38 MAP激酶和NF-？B（非经典IRE1途径），并且它们的激活可以诱导粘蛋白转录，因此IRE1也可能在功能上与粘蛋白产生有关。 IRE1 exists in two isoforms, 1 and 2. We found that IRE1a was ubiquitously expressed, but IRE1¿ While IRE1¿ expression was > 30 fold higher than IRE1a expression in HBE, IRE1¿ In mouse tissues, IRE1¿2 In wild-type (wt) mice, IRE1¿ was expressed in Clara cells and ovalbumin (OVA)-induced mucous cells, but was纤毛细胞中没有，这表明IRE1的特定功能与粘蛋白的产生有关。在IRE1�与WT小鼠中，OVA增强的气道上皮MUC5B和MUC16的产生被钝化。 IRE1在粘蛋白产生中具有关键功能作用的进一步证据是通过IRE1与粘蛋白产生或糖基化涉及的基因之间的强相关性给出的。我们的具体目的将检验一个主要的假设，即IRE1¿是通过气道粘液细胞产生粘蛋白所必需的，它刺激粘蛋白转录和/或调节与粘蛋白产生或糖基化有关的基因，其作用与IRE1A的作用不同，而IRE1损坏IRE1€将减少对人类空气中的粘液生产的粘液过度生产。研究将利用以粘液细胞化学和粘蛋白过量生产为特征的气道炎症体内和体内模型。 WT和IRE1�的原发性培养物 - / - 鼠气上皮，HBE表达不同水平IRE1¿的原发性培养物以及在气道上皮中表现出IRE1的SCNNN1B小鼠将用于测试IRE1在粘蛋白产生中的作用。这些新的研究可能会通过揭示IRE1€作为哮喘，COPD和CF气道疾病的治疗靶点而产生很大的影响。公共卫生相关性：粘蛋白过量生产特征许多气道炎症性疾病。我们的研究将测试IRE1¿的功能作用，IRE1¿是一种参与内质网应激反应的蛋白质，在与气道注射相关的粘蛋白产生中，并可能导致哮喘，COPD和CF患者的新疗法。