Glycosylation as a Structural Determinant in Peptide Fibrillization

糖基化作为肽纤维化的结构决定因素

• 批准号: 10649457
• 负责人: Gregory Hudalla
• 金额: $ 37.56万
• 依托单位: UNIVERSITY OF FLORIDA
• 依托单位国家: 美国
• 财政年份: 2019
• 资助国家: 美国
• 起止时间: 2019-09-01 至 2024-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10649457
• 关键词: Architecture; Binding; Biocompatible Materials; Biological; Biological Models; Biophysics; Carbohydrate Chemistry; Carbohydrates; Cartilage; Cell surface; Data; Degenerative polyarthritis; Disease; Equilibrium; Future; Glycoproteins; Health; Human; Joints; Kinetics; Knowledge; Libraries; Lubrication; Mediating; Methods; Modification; Molecular; Morphology; Mucins; Nature; Peptides; Production; Property; Protein Glycosylation; Proteins; Research; Role; Sorting; Surface; Testing; analog; beta pleated sheet; biophysical techniques; carbohydrate analog; carbohydrate binding protein; carbohydrate receptor; cost effective; design; glycosylation; insight; lubricin; nanofiber; prevent; programs; protein folding; self assembly; structural determinants; success

Project Summary. All human cell surfaces and nearly half of all human proteins are decorated with carbohydrates (i.e., glycosylated), yet our understanding of the role of glycosylation in health and disease remains limited. Increasing evidence is establishing a central role for glycosylation as a determinant of protein folding, sorting, processing, export, and function. Advancing this understanding requires platforms to systematically study changes in protein form and function resulting from altered glycosylation, which has historically required highly specialized expertise in protein production and carbohydrate synthesis. As a practical alternative, my research program develops carbohydrate-modified peptides that self-assemble into fibrillar architectures as synthetic analogs of glycosylated proteins. The proposed research program will study how glycosylation influences peptide fibrillization as a surrogate for protein folding, and will use these insights to enable design of new biomaterials. Preliminary data supporting the proposed research demonstrate that glycosylation can facilitate hierarchical self-assembly of a synthetic b-sheet fibrillizing peptide into anisotropic networks of aligned nanofibers. These anisotropic networks resist non-specific biological interactions yet selectively recognize carbohydrate-binding proteins due to the emergent function of carbohydrates assembled into a multivalent architecture. The overarching hypothesis of the proposed research is that glycosylation influences peptide fibrillization and nanofiber function by establishing intermolecular forces that mediate specific binding interactions while preventing non-specific associations. To test this, we will first develop a method for scalable, cost-effective synthesis of a library of fibrillizing peptides modified with a broad range of carbohydrate chemistries. Then we will use this library to study the influence of glycosylation on the kinetics of peptide fibrillization and equilibrium morphology of the resultant nanofibers using various biophysical methods. Together, these studies will establish fundamental understanding of glycosylation as a structural determinant in peptide fibrillization. Finally, we will evaluate glycosylated peptide nanofibers as biomaterials that recapitulate the form and function of lubricin, a cartilage glycoprotein that provides boundary lubrication at the joint surface, which is lost during osteoarthritis progression. Although we use synthetic fibrillizing peptides as a model system, general observations made through this research program are expected to be applicable to the biophysics of natural fibrillizing peptides, and may also inform understanding of mucins and other densely glycosylated proteins. Success of this research will advance the field of supramolecular biomaterials by establishing carbohydrates as a new class of molecular motif for controlling peptide fibrillization. Ultimately, this research will support future efforts to develop biomaterials with new structural and functional properties that are desirable for biomedical applications by creating peptides modified with diverse carbohydrate chemistries found throughout nature.

项目摘要。所有人类细胞表面和近一半的人类蛋白质都装饰有 碳水化合物（即糖基化），但我们对糖基化在健康和疾病中的作用的理解 仍然有限。越来越多的证据表明糖基化作为蛋白质的决定因素发挥着核心作用 折叠、分类、加工、出口和功能。推进这种理解需要平台 系统地研究糖基化改变导致的蛋白质形式和功能的变化，这已 历史上需要蛋白质生产和碳水化合物合成方面高度专业的专业知识。作为一个实用的 或者，我的研究项目开发了碳水化合物修饰的肽，可以自组装成纤维状 作为糖基化蛋白质的合成类似物的结构。拟议的研究计划将研究如何 糖基化影响肽纤维化作为蛋白质折叠的替代物，并将利用这些见解 实现新生物材料的设计。支持拟议研究的初步数据表明 糖基化可以促进合成b-片原纤维化肽的分层自组装成各向异性 排列整齐的纳米纤维网络。这些各向异性网络还可以抵抗非特异性生物相互作用 由于碳水化合物组装的新兴功能，选择性识别碳水化合物结合蛋白 进入多价架构。本研究的总体假设是糖基化 通过建立介导特定的分子间力来影响肽纤维化和纳米纤维功能 结合相互作用，同时防止非特异性关联。为了测试这一点，我们首先开发一种方法 可扩展、经济高效地合成用多种碳水化合物修饰的纤维化肽库 化学。然后我们将利用这个库来研究糖基化对肽动力学的影响 使用各种生物物理方法对所得纳米纤维进行原纤化和平衡形态。一起， 这些研究将建立对糖基化作为肽结构决定因素的基本理解 纤维化。最后，我们将评估糖基化肽纳米纤维作为生物材料的形式 以及润滑素的功能，润滑素是一种软骨糖蛋白，可在关节表面提供边界润滑， 在骨关节炎进展过程中丢失。尽管我们使用合成的纤维化肽作为模型系统，但一般来说 通过该研究计划获得的观察结果预计将适用于自然生物物理学 纤维化肽，也可能有助于理解粘蛋白和其他密集糖基化蛋白质。 这项研究的成功将通过将碳水化合物确立为超分子生物材料领域 一类用于控制肽原纤维化的新型分子基序。最终，这项研究将支持未来 努力开发具有生物医学所需的新结构和功能特性的生物材料 通过创建用自然界中发现的多种碳水化合物化学物质修饰的肽来实现应用。