Fibronectin-dependent mechanisms governing the assembly of a definitive extracellular matrix

纤连蛋白依赖性机制控制最终细胞外基质的组装

• 批准号: 9923444
• 负责人: Jean E Schwarzbauer
• 金额: $ 34.55万
• 依托单位: PRINCETON UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2018
• 资助国家: 美国
• 起止时间: 2018-05-01 至 2023-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9923444
• 关键词: Address; Affect; Arthritis; Binding; Binding Proteins; Binding Sites; Biological Assay; Biological Models; Cell Differentiation process; Cell physiology; Cells; Chondrogenesis; Collagen; Collagen Fibril; Collagen Type I; Connective Tissue Diseases; Data; Defect; Development; Disease; Disease Outcome; Elements; Engineering; Enzymes; Extracellular Matrix; Extracellular Matrix Proteins; Fiber; Fibronectins; Fibrosis; Foundations; Glycosaminoglycans; Goals; Heparin; Heparitin Sulfate; Human; In Vitro; Knowledge; Lead; Link; Malignant Neoplasms; Mediating; Molecular; Molecular Conformation; Mutation; Normal tissue morphology; Pathogenicity; Pathologic Processes; Pathology; Patients; Process; Procollagen; Production; Property; Proteins; Pulmonary Fibrosis; Recombinant Proteins; Regulation; Research; Role; Route; Structure; System; Testing; Tissues; Work; base; chemical property; design; experimental study; fibrillogenesis; glomerulosclerosis; human disease; improved; insight; mechanical properties; mutant; novel; physical property; protein protein interaction; receptor; skeletal abnormality; skeletal dysplasia; tissue repair; treatment strategy; tumorigenesis

PROJECT SUMMARY The proposed work seeks to uncover novel mechanisms governing the assembly of the extracellular matrix (ECM) protein fibronectin (FN) and its role in directing assembly of other ECM proteins to form a definitive matrix. Because the definitive matrix is integral to key physical, chemical, and mechanical properties that regulate tissue structures and functions, understanding mechanisms that coordinate the assembly of FN with type I collagen and other ECM proteins is crucial. Molecular defects in matrix assembly are implicated in fibrosis in which disordered ECM fibers accumulate due to abnormal production of FN, collagen I, and other matrix proteins. Along with fibrosis, skeletal abnormalities, tumorigenesis, and other ECM-related diseases affect millions of people around the globe yet in most cases the ECM defects are poorly understood and, in many ways, still largely untreatable. The proposed work will test the hypothesis that the organization and insolubility of the pericellular FN matrix control and direct the assembly of a tissue-appropriate definitive matrix, and that perturbation of the FN matrix disrupts tissue and cell functions leading to disease. We have a general understanding of the main steps of FN matrix assembly, but specific mechanisms governing FN fibril organization, fibril stability, or how FN guides assembly of collagens have yet to be elucidated. The proposed aims will address these mechanisms, building on the foundation that we have established with our previous work. We will use our proven matrix assembly systems to analyze the formation of FN fibrils and their contributions to type I collagen assembly to determine the protein interactions that are critical for directing definitive matrix assembly. The goal of Aim 1 is to determine the mechanism that converts reversible FN-FN interactions into stable insoluble fibrils. We will test a new hypothesis that heparin/heparan sulfate acts as a molecular switch by binding to FN and inducing conformational changes that promote strong protein-protein interactions. Aim 2 will address the hypothesis that FN matrix acts as a template for collagen fibrillogenesis by providing a platform for the localization and activation of collagen processing enzymes. Aim 3 will link FN assembly with cell differentiation. Using a newly discovered human FN mutation potentially linked to a skeletal dysplasia, we will determine the matrix assembly defect caused by this mutation and will apply the micromass chondrogenesis model system to understand the effects of mutant FN matrix on cell differentiation. Our work will fill critical knowledge gaps in our understanding of the mechanisms governing key steps in the assembly of a definitive matrix, and will suggest routes by which pathological processes or mutations can cause abnormal matrix organization or accumulation. This work will generate new ideas for strategies to manipulate ECM assembly in order to treat or control fibrosis and other ECM-related diseases and may lead to ECM-based treatments to improve disease outcomes.

项目概要 拟议的工作旨在揭示控制细胞外组装的新机制 基质 (ECM) 蛋白纤连蛋白 (FN) 及其在指导其他 ECM 蛋白组装形成 确定矩阵。因为最终的矩阵是关键物理、化学和机械性能不可或缺的一部分 调节组织结构和功能，了解协调 FN 组装的机制 与 I 型胶原蛋白和其他 ECM 蛋白的结合至关重要。基质组装中的分子缺陷涉及 纤维化，其中由于 FN、胶原蛋白 I 和其他物质的异常产生而导致无序的 ECM 纤维积聚 基质蛋白。伴随纤维化、骨骼异常、肿瘤发生和其他 ECM 相关疾病 影响着全球数百万人，但在大多数情况下，人们对 ECM 缺陷知之甚少，并且 有很多方法，但基本上仍然无法治愈。拟议的工作将检验以下假设：组织和 细胞周围 FN 基质的不溶性控制并指导组织适当的最终基质的组装， FN 基质的扰动会破坏组织和细胞功能，导致疾病。我们有一个将军 了解 FN 基质组装的主要步骤，但控制 FN 原纤维的具体机制 组织、原纤维稳定性或 FN 如何引导胶原蛋白组装尚未阐明。拟议的 目标将在我们之前建立的基础上解决这些机制问题 工作。我们将使用我们经过验证的矩阵组装系统来分析 FN 原纤维的形成及其 对 I 型胶原组装的贡献，以确定对于指导至关重要的蛋白质相互作用 最终矩阵组装。目标 1 的目标是确定将可逆 FN 转化为 FN 的机制 相互作用形成稳定的不溶性原纤维。我们将测试一个新的假设，即肝素/硫酸乙酰肝素充当 通过与 FN 结合并诱导构象变化来促进强蛋白质-蛋白质的分子开关 互动。目标 2 将解决 FN 基质作为胶原纤维生成模板的假设： 为胶原蛋白加工酶的定位和激活提供平台。目标3将链接FN 组装与细胞分化。利用新发现的人类 FN 突变可能与骨骼相关 发育不良，我们将确定由这种突变引起的基质组装缺陷，并应用微团 软骨形成模型系统，以了解突变型 FN 基质对细胞分化的影响。我们的工作 将填补我们对控制组装关键步骤的机制的理解方面的关键知识空白 一个明确的矩阵，并将建议病理过程或突变可能导致异常的途径 矩阵组织或积累。这项工作将为操纵 ECM 的策略产生新的想法 组装以治疗或控制纤维化和其他 ECM 相关疾病，并可能导致基于 ECM 的 改善疾病结果的治疗。