DYSTROGLYCAN FUNCTION IN DEVELOPING BASEMENT MEMBRANES

肌营养不良聚糖是一种直接与 肌营养不良症的病理学基础， 疾病然而，肌营养不良蛋白聚糖的基本功能仍然存在， 不清楚肌营养不良蛋白聚糖敲除小鼠显示出早期的 胚胎致死表型与赖歇特膜缺陷 胚胎基底膜详细的表型表明， 肌营养不良聚糖是组装所需的假设 细胞外基质蛋白质进入基底膜结构。 本提案中概述的实验旨在验证这一点 假设作为一个步骤，朝着长期目标的理解， dystroglycan的生物学作用。这四个具体目标 建议是：1）确定分子和细胞基础 在抗肌营养不良蛋白聚糖敲除中的赖歇特膜缺陷 2）肌营养不良蛋白聚糖在Reichert's 器官培养系统中的膜组件;和，3）分析 胚状体中的基膜组装来自 肌营养不良聚糖缺失ES细胞。支持这些目标的实验 涉及肌营养不良蛋白聚糖敲除胚胎的原位分析， 使用细胞和器官培养模型测试肌营养不良蛋白聚糖在 基底膜组装由于基底膜是 正常组织结构和功能的基本特征， 了解肌营养不良蛋白聚糖在它们发育中的作用， 理解涉及基底细胞的人类疾病的重要性 膜，如肌营养不良症。

Dystroglycan is a molecule that is directly relevant to the pathology underlying muscular dystrophy and perhaps other human diseases. However, the basic function of dystroglycan remains unclear. The dystroglycan knockout mouse displays an early embryonic lethal phenotype with defects in Reichert's membrane- an embryonic basement membrane. The detailed phenotype suggests the hypothesis that dystroglycan is required for the assembly of extracellular matrix proteins into a basement membrane structure. The experiments outlined in this proposal are designed to test this hypothesis as a step toward the long term goal of understanding the biological role of dystroglycan. The four specific aims of this proposal are: 1) Determination of the molecular and cellular basis for the defect in Reichert's membrane in dystroglycan knockout embryos; 2) Analysis of the role of dystroglycan in Reichert's membrane assembly in an organ culture system; and, 3) Analysis of basement membrane assembly in embryoid bodies derived from dystroglycan-null ES cells. The experiments supporting these aims involve in situ analysis of dystroglycan knockout embryos, and the use of cell and organ culture models to test dystroglycan's role in basement membrane assembly. Since basement membranes are fundamental features of normal tissue structure and function, understanding dystroglycan's role in their development should have importance for understanding human disorders involving basement membranes, such as the muscular dystrophies.