PROPERTIES OF CALCIUM PUMPING ATPASE

描述。人体组织结构与功能关系的研究 质膜上的钙泵ATPase将继续存在。这些钙离子 泵存在于心脏、平滑肌、肾脏、大脑的质膜中， 肠上皮、红细胞等多种细胞类型。他们是 参与各种细胞内钙离子水平的控制，以及 在钙离子跨上皮细胞层的移动中，如肠道和 肾小管上皮细胞。关于这些泵的调节信息 因此可以提供与高血压和肾脏疾病有关的信息，其中 其他条件。 该泵由一个分子量多肽链组成。 127,000-137,000(确切的分子量取决于异构体)。四 基因编码不同的异构体，其他形式由 备用接头。申请人的实验室已经成功地表达了 这种泵作用于COS细胞，并开发了一种检测系统，用于检测 表达的酶的活性。建议进行研究，以延长 目前关于这种酶不同部分的功能的知识。 结构-功能关系将通过站点导向进行映射 诱变(利用COS细胞系统)。异构体的性质 将确定哪种形式将有助于定义不同形式的角色。 将开发抗体来识别在不同基因中表达的亚型 单元类型。

DESCRIPTION. Studies on the relationship between structure and function in the Ca2+ pumping ATPase of plasma membranes will be continued. These Ca2+ pumps exist in the plasma membranes of heart, smooth muscle, kidney, brain, intestinal epithelium, erythrocyte and many other cell types. They are involved in control of intracellular Ca2+ levels in cells of all kinds, and in movement of Ca2+ across epithelial cell layers such as the intestinal and kidney tubule epithelium. Information about the regulation of these pumps may thus give information relevant to hypertension and kidney disease, among other conditions. The pump consists of a single polypeptide chain of molecular weight 127,000-137,000 (the exact molecular weight depends on the isoform). Four genes encode different isoforms, and additional forms are created by alternate splices. The applicant's laboratory has succeeded in expressing this pump on COS cells and have developed an assay system for determining the activity of the expressed enzyme. Studies are proposed to extend the present knowledge of the function of the different parts of this enzyme. The structure-function relationships will be mapped by site-directed mutagenesis (utilizing the COS cell system). The properties of the isoforms will be determined which will hep to define the role of the different forms. Antibodies will be developed to identify the isoforms expressed in different cell types.