MECHANISMS OF PROTEOGLYCAN/COLLAGEN INTERACTIONS

蛋白聚糖/胶原蛋白相互作用的机制

• 批准号: 2901197
• 负责人: James D SanAntonio
• 金额: $ 11.34万
• 依托单位: THOMAS JEFFERSON UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 1997
• 资助国家: 美国
• 起止时间: 1997-04-01 至 2001-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/2901197
• 关键词: chemical binding; collagen; electrophoresis; intermolecular interaction; laboratory rat; molecular site; protein structure function; proteoglycan; recombinant proteins

Proteoglycan-collagen interactions are ubiquitous in most vertebrate tissues and likely play key roles in cell adhesion, migration, and extracellular matrix (ECM)assembly and function. Although the biochemistry of the binding between the cell surface or secreted proteoglycans and collagens is incompletely understood, a primarily electrostatic, non-specific basis for their interactions has been proposed. However, by electron microscopy this laboratory has observed heparin binding to specific regions on type I collagen monomers and fibrils, and using affinity coelectrophoresis has shown that high affinity collagen-binding domains comprise only a small fraction of the heparin molecule. These results favor the hypothesis that high affinity heparin-type I collagen binding depends more upon unique, sparsely represented domains or sequences within the glycosaminoglycan and protein, than upon site-independent electrostatic interactions. To test the above hypothesis, first, the collagen-binding sites of heparin will be isolated and their abundance, size, sequence, and binding selectivity for other ECM molecules will be determined by affinity coelectrophoresis (ACE) and other biochemical approaches. Second, the putative heparin-binding regions of type I collagen will be confirmed by studying the interactions of heparin with a) recombinant type I collagens in which D-period segments have either been deleted or inserted in multiple copies, or in altered positions, and b) with "mini collagen" peptides carrying known type I collagen sequences. Last, the identified interactive domains of heparin and type I collagen will be tested in cell interactions with type i collagen and with other ECM molecules. These studies will define the biochemistry and function of one of the most abundant of cell-matrix interactions, and contribute to the understanding and treatment of diseases such as cancer which involve abnormal cell adhesion and migration within the ECM.

蛋白聚糖-胶原蛋白相互作用在大多数脊椎动物中普遍存在 组织并可能在细胞粘附、迁移和 细胞外基质（ECM）的组装和功能。虽然 细胞表面或分泌物之间结合的生物化学 蛋白多糖和胶原蛋白尚不完全了解，主要是 它们相互作用的静电、非特异性基础 建议的。然而，通过电子显微镜，该实验室发现 观察到肝素与 I 型胶原蛋白的特定区域结合 单体和原纤维，并使用亲和共电泳显示 高亲和力胶原蛋白结合域仅包含一小部分 肝素分子的分数。这些结果支持假设 高亲和力肝素 I 型胶原蛋白结合更多地取决于 独特的、稀疏表示的域或序列 糖胺聚糖和蛋白质，而不是位点无关的 静电相互作用。 为了验证上述假设，首先，胶原蛋白结合位点 肝素将被分离，其丰度、大小、序列和 对其他 ECM 分子的结合选择性将由下式确定 亲和共电泳（ACE）和其他生化方法。 其次，I 型胶原蛋白的假定肝素结合区域将 通过研究肝素与 a) 的相互作用来证实 重组 I 型胶原蛋白，其中 D 期片段具有 被删除或插入多个副本，或改变位置， b) 带有携带已知 I 型胶原蛋白的“迷你胶原蛋白”肽 序列。最后，已确定的肝素和肝素的相互作用域 I 型胶原蛋白将在细胞与 I 型胶原蛋白的相互作用中进行测试 以及其他 ECM 分子。这些研究将定义 最丰富的细胞基质之一的生物化学和功能 互动，并有助于理解和治疗 涉及细胞粘附异常的疾病，例如癌症 ECM 内的迁移。