MINERAL INDUCTION BY IMMOBILIZED DENTIN PHOSPHOPROTEIN

固定化牙本质磷酸蛋白的矿物质诱导

• 批准号: 3425368
• 负责人: MILES A CRENSHAW
• 金额: $ 2.17万
• 依托单位: UNIV OF NORTH CAROLINA CHAPEL HILL
• 依托单位国家: 美国
• 财政年份: 1988
• 资助国家: 美国
• 起止时间: 1988-09-30 至 1990-09-29
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/3425368
• 关键词: X ray crystallography; acidity /alkalinity; atomic absorption spectrometry; biological models; calcification; calcium metabolism; collagen; dentin; extracellular matrix; infrared spectrometry; macromolecule; phosphates; phosphoproteins; solutions; spectrometry

The long-term objective of this research is to gain insights into the mechanisms of biomineralization by determining the capacities of isolated matrix proteins to induce and to promote mineral formation. The purpose of the proposed research is to conduct pilot studies on the mineralization potential of dentin phosphoprotein using an in vitro model system. In this sytem dentin phosphoprotein will be immobilized by covalent linkage to a model substrate, polyacrylamide, to simulate its attachment to the collagen network of dentin. The capacity of the immbolized phosphoprotein to induce mineral formation from metastable solutions which do not spontaneously precipitate and that maintained at constant calcium ad phosphate activities, approximating those of body fluids, will be determined. The phosphoprotein also will be added, in solution, to determine the effects the free protein on the formation and growth of mineral induced by the immobilized protein. The calcium and phosphate concentrations and pH will be held constant with a chemostat that senses minute changes in the incubation solution and corrects for these changes by addition of the ions. Atomic spectroscopy and colorimetry will be used to ascertain that the incubation solution is maintained at cosntant composition. The capacity to induce mineral will be determined in terms of the time lag until the first mineral is formed and the rate of mineral formation. The type of mineral formed will be determined by X-ray diffraction and infrared spectrophotometry. The results obtained in this proposed investigation will contribute to an understanding of the normal mechanisms of mineral induction in calcified tissues. The results will also have implications in the pathological disorders in which the normal mineralization patterns are absent, such as some types of dentiogenesis imperfecta whee the dentin phosphoprotein seems to be absent.

这项研究的长期目标是深入了解 生物矿化的机制，通过测定容量 分离的基质蛋白诱导和促进矿物质 阵 拟议研究的目的是进行 牙本质矿化潜能的初步研究 使用体外模型系统测定磷蛋白。 在这个系统中， 牙本质磷蛋白将通过共价键固定， 一个模型基板，聚丙烯酰胺，以模拟其附件， 牙本质的胶原网络。 固定化的能力 磷蛋白诱导矿物质从亚稳态形成 不会自发沉淀的溶液， 保持恒定的钙和磷酸盐活性， 与体液相似，将被确定。 的 还将在溶液中加入磷蛋白，以确定 游离蛋白质对矿物形成和生长的影响 由固定化蛋白质诱导。 将保持钙和磷酸盐浓度和pH值 恒定的恒化器，它能感知 孵育溶液，并通过添加 离子。 原子光谱法和比色法将用于 确保孵育溶液保持浓度 混合物. 将确定诱导矿物的能力 就第一种矿物形成的时间滞后而言， 矿物形成的速度。 形成的矿物类型将是 用X射线衍射法和红外光谱法测定。 在这项拟议的调查中获得的结果将有助于 了解矿物的正常机制 在钙化组织中诱导。 结果也将有 在病理性疾病的影响，其中正常 没有矿化模式，例如某些类型的 牙本质磷蛋白似乎 缺席。