LECTIN-LIKE PROPERTIES OF AMELOGENINS

釉蛋白的类凝集素特性

• 批准号: 2836685
• 负责人: ALAN G FINCHAM
• 金额: $ 24.23万
• 依托单位: UNIVERSITY OF SOUTHERN CALIFORNIA
• 依托单位国家: 美国
• 财政年份: 2000
• 资助国家: 美国
• 起止时间: 2000-02-01 至 2005-01-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/2836685
• 关键词: N acetylglucosamine; agglutination reaction; ameloblasts; amelogenin; apatites; atomic force microscopy; biological signal transduction; disease /disorder model; electron microscopy; extracellular matrix proteins; glycolipids; glycoproteins; histochemistry /cytochemistry; histogenesis; intermolecular interaction; laboratory mouse; lectin; membrane proteins; model design /development; normal ossification; odontoblasts; oligosaccharides; protein binding; protein structure function; tooth enamel

DESCRIPTION (adapted from the Investigator's abstract): The long-term objective of this proposal is to determine the nature and function of amelogenins with sugar residues of other enamel proteins, and cell surface glycoconjugates. The central hypothesis is that amelogenins have lectin-like properties, which mediate functional protein-carbohydrate interactions with matrix glycoproteins or cell surface glycoconjugates within the matrix or at the dentine enamel junction (DEJ). Preliminary data from the Principal Investigator's laboratory have established the presence of and amelogenin glyco-binding motif located in the conserved amino terminal region of the molecule. Others have established that a mutation in this region of the amelogenin structure results in the clinical enamel defect; amelogenesis imperfecta. (Collier et al., 1997). To test this hypothesis the following five specific aims will be investigated. The first aim is to identify specific interactions between amelogenins and structural analogs of N-acetyl glucosamine (GlcNAc) and N-acetyl neuraminic acid (NeuAC) and their glycosidic linkages commonly found in mammalian glycoproteins and glycolipids. Agglutination and competitive inhibition studies of amelogenins with oligosaccharides and glycoconjugates. (2) To identify putative ligands for amelogenin-binding in the extracellular enamel matrix "non-amelogenin" glycoprotein fractions. The lectin histochemistry of non-amelogenin proteins and immunological and radiometric assessment of amelogenin binding to these proteins is studied. (3) To assess the influence of carbohydrate-amelogenin interactions on nanosphere formation. Conjugates of glycoproteins and amelogenins are studied employing electron and atomic-force microscopy. (4) To evaluate the effects of GlcNAc/NeuAc-rich non-amelogenins and glycoprotein analogs on biomineralization in the presence and absence of amelogenin in vitro. The effects of glycoconjugates and amelogenins of apatite biomineralization are assessed. (5) To develop a model for the recognition and binding of amelogenins with cell surface glycoconjugates of odontoblasts and ameloblasts and to determine the effects of amelogenin-derived peptides on amelogenesis in vitro. A fibroblast model is developed and cell-surface amelogenin interactions and the putative role of amelogenin peptides in a feedback-signaling pathway are investigated. These experiments are a logical extension of the newly identified lectin-like properties of amelogenins (Ravindranath et al. Submitted), which are postulated to play a functional role in normal enamel biomineralization.

描述（改编自研究者的摘要）：长期目标 该提案的目的是确定牙釉蛋白的性质和功能 其他牙釉质蛋白的糖残基和细胞表面糖复合物。这 中心假设是牙釉蛋白具有类似凝集素的特性， 介导功能性蛋白质-碳水化合物与基质糖蛋白的相互作用 或基质内或牙本质釉质处的细胞表面糖缀合物 交界处（DEJ）。来自首席研究员实验室的初步数据 已经确定了牙釉蛋白糖结合基序的存在，位于 分子的保守氨基末端区域。其他人已成立 牙釉蛋白结构的该区域的突变导致 临床牙釉质缺陷；釉质形成不完善。 （科利尔等人，1997）。到 检验这一假设将研究以下五个具体目标。这 第一个目标是确定釉原蛋白和 N-乙酰氨基葡萄糖 (GlcNAc) 和 N-乙酰神经氨酸的结构类似物 酸 (NeuAC) 及其糖苷键常见于哺乳动物 糖蛋白和糖脂。凝集和竞争性抑制研究 牙釉蛋白与寡糖和复合糖的混合物。 (2) 识别 细胞外牙釉质基质中釉原蛋白结合的推定配体 “非釉原蛋白”糖蛋白部分。凝集素组织化学 非釉原蛋白以及免疫学和放射学评估 研究了牙釉蛋白与这些蛋白质的结合。 (3) 评估影响 碳水化合物-牙釉蛋白相互作用对纳米球形成的影响。共轭物 利用电子和原子力研究糖蛋白和牙釉蛋白 显微镜。 (4) 评价富含GlcNAc/NeuAc的非釉原蛋白的作用 和糖蛋白类似物在存在和不存在的情况下对生物矿化的影响 体外釉原蛋白。磷灰石复合糖和釉原蛋白的作用 评估生物矿化。 (5) 建立识别模型 牙釉蛋白与成牙本质细胞表面糖复合物的结合 成釉细胞并确定釉原蛋白衍生肽对成釉细胞的影响 体外釉质形成。开发了成纤维细胞模型并研究了细胞表面 牙釉蛋白相互作用以及牙釉蛋白肽在 反馈信号通路进行了研究。这些实验是合乎逻辑的 新发现的牙釉蛋白类凝集素特性的扩展 （Ravindranath 等人提交），假设发挥功能作用 在正常的牙釉质生物矿化中。