Ultrastructure

项目摘要 (See说明）：核心D将进行支持所有其他项目所需的定性和定量组织学和超微结构检查。Core不仅提供电子、相衬和共聚焦显微镜的各种技术，而且还将以高质量标准运行，并对实验和分子改变的结果提供专家的关键评估。高质量图像的统一和一致使用将允许检测蛋白质-蛋白质相互作用和单个细胞器响应中的甚至细微的改变，这些改变是功能改变的基础或这种改变的长期结果。很明显，肌纤维对影响兴奋-收缩偶联的突变的总体超微结构反应是相当特异的，并提供了对致病效应的相当深入的了解。在过去的一段时间里，我们已经证明了一个强大的纤维类型和性别依赖性的病理学，这与类似的功能变化相当吻合。提出了两种一般方法。一个是确定钙释放单位的主要蛋白质组分之间关系的任何改变（CRU，骨骼肌中的三合会）内的突变，另一种是遵循病理的发展（最特别是线粒体，肌原纤维和CRU的改变）通过发展和老化，并与已知的功能影响的突变对CRU的渠道。这将实现结合光学显微镜技术（纤维整体安装的相位对比和荧光免疫标记的纤维的共聚焦成像），薄切片和冷冻断裂用于电子显微镜，辅以定量形态测定技术。核心的目的是确定每个突变在短期内对钙释放单位的大分子组装的主要影响，以及长期对SR，线粒体和收缩物质的次要影响

PROJECT SUMMARY (See instructions): Core D will perform the qualitative and quantitative histological and ultrastructural checks that are necessary to support all other Projects. The Core will not only supply various techniques of electron, phase contrast and confocal microscopy, but it will also operate at a high standard of quality and offer an expert critical evaluation of the results of experimental and molecular alterations. The uniform and consistent use of high quality images will allow the detection of even subtle alterations in protein-protein interactions and in the response of individual cell organelles that either are at the basis of altered functions or are the long term results of such alterations. It is clear that the overall ultrastructural response of the muscle fiber to mutations affecting excitation-contraction coupling are quite specific and offer considerable insight into causative effects. In the past period we have evidenced a strong fiber type- and gender-dependence of the pathology, that correspindes quite well with similar variations in function. Two general approaches are proposed. One is to define any alterations in the relationships between the major protein components of calcium release units (CRUs, triads in skeletal muscle) within the context of the mutation and the other is to follow the development of pathology (most specifically mitochondrial, myofibrillar and CRUs' alterations) through development and aging and in relation to the known functional effects of the mutation on CRUs' channels.This will be achieved by combining light microscope techniques (phase contrast of fibers whole mounts and confocal imaging of fluorescently immunolabeled fibers) with thin sectioning and freeze-fracture for electron microscopy supplemented by quantitative morphometry techniques. The core aims at defining the primary impact of each mutation on the macromelcular assembly of calcium release units within a short term and the secondary impact on SR, mitochondria and contractile material on the long term