LOCALIZATION OF PROCOLLAGENS IN DENTAL TISSUES

牙齿组织中原胶原的定位

基本信息

批准号：
3219572
负责人：
CHARLES P LEBLOND
金额：
$ 7.53万
依托单位：
MCGILL UNIVERSITY
依托单位国家：
美国
项目类别：
财政年份：
1981
资助国家：
美国
起止时间：
1981-08-01 至 1991-03-31
项目状态：
已结题

项目摘要

This application is designed to continue studies aimed at a clarification of the intracellular formation of various collagens. Enough progress has been made recently in the techniques of radioautography and immunohistochemistry at the electron microscopic level to make it possible to combine these methods on the same sections. Thus, at various times after in injection of 3H-proline, radioautographic silver grains (which are spherical and about 50 nm wide) and immunogold particles (15 nm) can be counted separately over the same organelle (rER cisterna, Golgi saccule, secretory granule). The ratio of the two counts will provide the specific activity of collagen precursors in each organelle and its variation with time. The turnover rate of the precursors will when be calculated at each step along the intracellular pathway of collagen. Specific activity measurements will be applied to the study of the biogenesis of type IV collagen in active chondrocytes, type I collagen in odontoblasts, type IV collagen in endodermal cells and type III collagen in periodontal fibroblasts. A second aim of the application is to continue the investigations of basement membrane and related structures. The major component of basement membrane is shown at high magnification of the electron microscope to be a tridimensional network of anastomosing strands, referred to as "cords", whose average width is 4 nm. It is planned to combine purified type IV collagen with other basement membrane components in vitro in the hope of reproducibly obtaining 50-100 nm sheets made up of a network of 4-nm cords, that is, sheets similar to the lamina densa of authentic basement membranes. A minor component of some basement membrane, the basotuble - a 9 nm wide rod of indefinite length - has been shown to have the same dimension and ultrastructure as the microfibrils of connective tissues. The main structural element of both is a core consisting of stacked molecules of amyloid P component (a glycoprotein known to be present in normal serum and to accumulate in amyloid degeneration). Three substances, i.e. fibronectin, fibrillin and a proteoglycan, have been shown to be associated with microfibrils. The aim of our work is to utilize immunolabeling for these substances using 5 nm gold particles to determine how they related to the amyloid P core of microfibrils and basotubules.

该应用程序旨在继续研究，旨在澄清各种胶原蛋白的细胞内形成。最近在技术方面已经取得了足够的进展电子放射自显影和免疫组织化学微观层面使将这些方法结合起来成为可能相同的部分。因此，在注射后的不同时间 3H-脯氨酸，放射自显影银颗粒（球形和可以计数约50 nm宽）和免疫金颗粒（15 nm）分别作用于同一细胞器（rER 池、高尔基体、分泌颗粒）。两个计数的比率将提供每个细胞器中胶原蛋白前体的比活性及其随时间的变化。前体的周转率将在沿着细胞内途径的每一步进行计算胶原。特定活动测量将应用于研究活性软骨细胞中 IV 型胶原蛋白的生物合成，成牙本质细胞中的 I 型胶原蛋白，内胚层中的 IV 型胶原蛋白牙周成纤维细胞中的细胞和 III 型胶原蛋白。该申请的第二个目的是继续调查基底膜及相关结构。主要成分在电子的高放大倍数下显示了基底膜的结构显微镜是一个三维网络的吻合线，称为“绳索”，其平均宽度为4纳米。已计划将纯化的 IV 型胶原蛋白与其他基底膜结合体外成分，希望可重复获得 50-100 nm片由4nm线组成的网络，即片材类似于真正的基底膜的致密层。某些基底膜的次要组成部分，基底管 - a 9 纳米宽的不定长度棒 - 已被证明具有相同的尺寸和超微结构作为结缔组织的微纤维组织。两者的主要结构元件都是由核心组成淀粉样蛋白 P 成分（一种已知的糖蛋白）的堆叠分子存在于正常血清中并积聚在淀粉样蛋白中退化）。三种物质，即纤连蛋白、原纤维蛋白和一种蛋白聚糖，已被证明与微原纤维有关。我们工作的目的是利用免疫标记来检测这些使用 5 nm 金颗粒确定物质之间的关系微原纤维和基底小管的淀粉样蛋白 P 核心。