MINERAL-MATRIX RELATIONS IN CALCIFYING TISSUES

钙化组织中矿物质与基质的关系

• 批准号: 3161897
• 负责人: WILLIAM J LANDIS
• 金额: $ 34.56万
• 依托单位: BOSTON CHILDREN'S HOSPITAL
• 依托单位国家: 美国
• 财政年份: 1992
• 资助国家: 美国
• 起止时间: 1992-05-01 至 1996-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/3161897
• 关键词: calcification; cartilage development; chickens; collagen; computer graphics /printing; electron probe spectrometry; extracellular matrix; growth /development; high voltage electron microscopy; laboratory mouse; laboratory rat; normal ossification; phosphoproteins; stereochemistry; tendons; tissue /cell culture; turkeys

The long term objective of this application is to obtain new information of the organization and chemistry of vertebrate skeletal tissues: bone, cartilage, and tendon. Investigation of calcification in normal and abnormal samples will examine interaction between mineral crystals and extracellular matrix and the precise role of collagen, vesicles, and certain phosphorylated proteins in mineral nucleation, growth and development. Mineralization will be studied initially in normal chicks, rats, mice, and turkeys as vertebrate model systems and later in examples of abnormal calcification including rickets, osteoporosis, calcergy, calciphylaxis, and osteopetrosis. Ultrastructural, biochemical, immunocytochemical, and biophysical methods will be applied to determine the presence, nature, location, and relation of mineral and organic matrix components in the respective tissues. Specifically, the hypothesis to be tested is: Certain phosphoproteins located in extracellular organic matrices of vertebrate tissues are required for the deposition of mineral in calcification. These phosphoproteins are associated with collagen and/or extracellular vesicles to provide critical nucleation sites for mineral formation. Growth and development of mineral subsequent to nucleation is under strict control of stereochemical and physicochemical constraints. The precise aims for examining this hypothesis are to 1) characterize in the calcifying systems the macromolecular stereochemistry of collagen fibrils and their spatial and structural relationship with phosphoproteins or extracellular vesicles using conventional and high voltage electron microscopy, three-dimensional computer image reconstruction, microscopic tomography, and simulated video techniques; 2) identify microscopic sites of mineral deposition through electron diffraction-dark field imaging, high resolution electron probe microanalysis, and topographic imaging in conjunction with conventional and anhydrous sample preparation and 3) determine the spatial and temporal interaction between mineral and phosphoproteins, collagen, and other organic matrix constituents through correlation of the above imaging methods. The data will contribute to knowledge of normal structure, organization, and physiological functions of cells and extracellular matrices of mineralizing tissues and fundamental events of vertebrate calcification.

该应用程序的长期目标是获取 脊椎动物骨骼组织的组织和化学：骨头， 软骨和肌腱。 调查正常钙化和 异常样品将检查矿物晶体与 细胞外基质以及胶原蛋白，囊泡和的精确作用 矿物质成核，生长和 发展。 矿化最初将在普通小鸡中进行研究， 大鼠，小鼠和火鸡作为脊椎动物模型系统，后来在示例中 异常钙化的钙化，包括瑞克斯，骨质疏松症，过敏症， 钙基质和骨质疏松症。 超微结构，生化， 将采用免疫细胞化学和生物物理方法来确定 矿物和有机基质的存在，性质，位置和关系 各个组织中的成分。 具体而言，假设为 测试是：某些位于细胞外有机物中的磷蛋白 矿物沉积需要脊椎动物组织的基质 在钙化中。 这些磷蛋白与胶原蛋白有关 和/或细胞外囊泡提供关键的成核位点 矿物形成。 矿物的生长和发展 成核严格控制立体化学和物理化学 约束。 研究这一假设的确切目的是1） 在钙化系统中表征大分子立体化学 胶原原纤维及其与空间和结构关系 使用常规和高的磷蛋白或细胞外囊泡 电压电子显微镜，三维计算机图像 重建，微观断层扫描和模拟视频技术； 2） 通过电子识别矿物沉积的微观位点 衍射黑色场成像，高分辨率电子探针 微分析和地形成像以及常规和 无水样品制备和3）确定空间和时间 矿物质和磷蛋白，胶原蛋白和其他磷蛋白之间的相互作用 通过上述成像的相关性有机基质成分 方法。 数据将有助于对正常结构的了解， 细胞和细胞外的组织和生理功能 矿化组织的矩阵和脊椎动物的基本事件 钙化。