Structure function studies in intestinal epithelial JAM

肠上皮JAM的结构功能研究

• 批准号: 7806653
• 负责人: CHARLES A PARKOS
• 金额: $ 30.43万
• 依托单位: EMORY UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2002
• 资助国家: 美国
• 起止时间: 2002-05-01 至 2012-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7806653
• 关键词: Actins; Acute; Antigens; Apical; Area; Binding; Binding Proteins; Biochemical; Biological Assay; Calcium; Cell Adhesion; Cell Culture System; Cell Line; Cell Shape; Cell surface; Cell-Matrix Junction; Cells; Characteristics; Chemicals; Chinese Hamster Ovary Cell; Clinical; Coculture Techniques; Colitis; Complex; Coxsackie Viruses; Crohn' s disease; Crosslinker; Cultured Cells; Data; Development; Diarrhea; Disease; Down-Regulation; Epithelial; Epithelial Cells; Epitopes; Event; Extracellular Domain; F-Actin; Family; Functional disorder; Gastrointestinal tract structure; Goals; Grant; Guanosine Triphosphate Phosphohydrolases; Histopathology; Human; Immunofluorescence Immunologic; Immunoprecipitation; In Vitro; Inflammatory; Inflammatory Bowel Diseases; Inflammatory disease of the intestine; Injury; Integral Membrane Protein; Integrins; Intercellular Junctions; Intestines; Liquid substance; Mediating; Molecular; Monomeric GTP-Binding Proteins; Movement; Mus; Mutation; Pathologic; Patients; Permeability; Physiological; Plasmids; Proteins; Reagent; Regulation; Relapse; Research Personnel; Role; Scaffolding Protein; Signal Pathway; Signal Transduction; Structure; Symptoms; Testing; Tight Junctions; Tissues; Toxin; Transfection; Ulcerative Colitis; Western Blotting; Withdrawal; adenovirus receptor; afadin; base; crosslink; cytokine; dimer; extracellular; genetic regulatory protein; in vivo; junctional adhesion molecule; member; monolayer; monomer; mutant; novel therapeutics; occludin; paralogous gene; programs; research study; solute; trafficking

DESCRIPTION (provided by applicant): The epithelial lining of the gastrointestinal tract forms a vital protective barrier that separates luminal antigens and toxins from the underlying tissue compartments. Patients with inflammatory bowel disease (IBD) encompassing both Crohn's disease and ulcerative colitis present clinically with relapsing intestinal inflammation and diarrhea. Numerous mechanisms have been proposed to explain these clinical symptoms and include defective intestinal epithelial barrier function. Increased paracellular permeability has been documented in the epithelial lining from both the acutely inflamed and chronically damaged areas of the intestine. Epithelial barrier function is regulated to a large extent by the apical most intercellular junction referred to as the tight junction (TJ). The TJ not only separates the lumenal compartment from the tissue space, but has been shown to regulate movement of solutes across the paracellular space in diverse physiologic and pathologic states. The transmembrane proteins in epithelial TJs include occludin, members of the claudin family, junctional adhesion molecule (JAM)-A and coxsackie and adenovirus receptor (CAR). Our studies indicate that JAM-A is a key TJ protein with several functions important in regulating intestinal epithelial barrier, cell shape and cell-matrix adhesion. In this proposal, we continue a structure-function based approach to study human JAM-A. The specific aims of this proposal are focused on determining intracellular events that mediate JAM-A function and the structural basis of extracellular homophilic interactions of JAM-A responsible for this. We will primarily utilize in vitro cell culture systems amenable to dissecting out biochemical and molecular events in intestinal epithelial cell lines in concert with in vivo studies in mice to highlight relevance. The long term goal is to correlate our findings on the molecular regulation of JAM-A function with pathophysiology in IBD. Understanding basic mechanisms regulating intercellular junctions and paracellular movement of fluids and solutes may provide clues to the pathophysiology of mucosal diseases such as IBD and aid in the development of new therapeutic strategies aimed at diminishing enhanced permeability and mucosal injury associated with these conditions.

描述（由申请人提供）：胃肠道的上皮衬里形成了一个重要的保护屏障，将腔抗原和毒素与潜在的组织室分开。炎症性肠病（IBD）的患者涵盖了克罗恩病和溃疡性结肠炎，临床上出现复发性肠炎和腹泻。已经提出了许多机制来解释这些临床症状，并包括有缺陷的肠上皮屏障功能。在肠道急性发炎和长期受损的肠道区域的上皮衬里中，细胞细胞通透性的增加。上皮屏障功能在很大程度上受到顶端最大的连接的调节，称为紧密连接（TJ）。 TJ不仅将腔室与组织空间分开，而且已显示可调节溶质在多种生理和病理状态下跨细胞细胞间空间的运动。上皮TJ中的跨膜蛋白包括闭合蛋白，Claudin家族的成员，连接粘附分子（JAM）-A和Coxsackie和Coxsackie和腺病毒受体（CAR）。我们的研究表明，JAM-A是一种关键的TJ蛋白，具有几种在调节肠上皮屏障，细胞形状和细胞矩阵粘附方面重要的功能。在此提案中，我们继续采用基于结构功能的方法来研究人类JAM-A。该提案的具体目的集中在确定介导JAM-A功能的细胞内事件以及JAM-A的细胞外同粒相互作用的结构基础。我们将主要利用可随意的体外细胞培养系统在肠上皮细胞系中与体内研究中的肠道上皮细胞系中的生化和分子事件进行解剖，以突出相关性。长期目标是将我们关于JAM-A功能分子调节的发现与IBD中的病理生理相关联。了解调节液体和溶质的细胞间连接和细胞细胞运动的基本机制可能为粘膜疾病的病理生理提供线索，例如IBD，并有助于开发旨在减少与这些疾病有关的增强渗透性和粘膜损伤的新治疗策略。