A CA-DEPENDENT MODULATOR PROTEIN OF THE NA-K ATPASE

NA-K ATP酶的CA依赖性调节蛋白

• 批准号: 3280854
• 负责人: DOUGLAS R YINGST
• 金额: $ 5.36万
• 依托单位: WAYNE STATE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 1984
• 资助国家: 美国
• 起止时间: 1984-04-01 至 1988-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/3280854
• 关键词: adenosinetriphosphatase; calcium; erythrocyte membrane; human subject; human tissue; hypertension; membrane permeability; membrane potentials; molecular weight

Recent work by the author has shown that the sensitivity of the Na-K ATPase and Na-K pump of human red blood cells to inhibition by Ca is increased 20 fold by an unidentified protein present in the cytoplasm of red cells. The protein is not calmodulin, appears to bind to the membrane of human red cells in a Ca-dependent manner and increases the sensitivity of the Na-K ATpase to the extent that 50% inhibition occur at low micromolar concentrations of free Ca. If this protein also alters the effect of Ca on the Na-K ATPase in other cells, then it could play a fundamental role in cellular regulation of the Na-K ATPase in other cells, then it could play a fundamental role in cellular regulation of the Na-K pump under many conditions. For instance, it could be involved in the relationship between the Na-K pump and the Na/Ca exchange and the control of free Ca in smooth muscle which may underlie the inotropic effect of cardiac glycosides and the relationship between sodium metabolism and hypertension. The first aim of the proposed project is to purify and identify the protein; the second is to determine its molecular weight, amino acid composition, end terminals, and possible prosthetic groups. The third aim is to study the effect of the purified protein on Ca inhibition of the Na-K ATPase in human red cell membranes and the fourth is to establish the effect on the purified Na-K ATPase in human red cell membranes and the fourth is to establish the effect on the purified Na-K ATPase. The fifth and final aim is to investigate if the Na-K ATPase in patients with essential hypertension are more sensitive than normal to inhibition by Ca and to establish what role the purified protein may play in such differences.

作者最近的工作表明 Na-K ATP 酶的敏感性 人红细胞的 Na-K 泵对 Ca 的抑制增加 20 被红细胞细胞质中存在的未知蛋白质折叠。 这 蛋白质不是钙调蛋白，似乎与人红细胞膜结合 细胞以 Ca 依赖性方式并增加 Na-K 的敏感性 ATpase 达到在低微摩尔浓度下发生 50% 抑制的程度 游离 Ca 浓度。 如果这种蛋白质也改变 Ca 对 其他细胞中的 Na-K ATP 酶，那么它可以在 其他细胞中 Na-K ATP 酶的细胞调节，然后它可以发挥 Na-K 泵在许多情况下的细胞调节中发挥着重要作用 状况。 例如，它可能涉及以下关系： Na-K 泵和 Na/Ca 交换以及自由 Ca 的平稳控制 可能是强心苷的正性肌力作用的肌肉， 钠代谢与高血压的关系。 该项目的首要目标是纯化和鉴定 蛋白质;二是测定其分子量，氨基酸 组成、末端和可能的假体基团。 第三个目标 目的是研究纯化蛋白对 Ca 对 Na-K 的抑制作用 第四个是建立人红细胞膜中的 ATPase 对人红细胞膜中纯化的 Na-K ATP 酶的影响 第四是确定对纯化的 Na-K ATP 酶的影响。 第五 最终目的是调查 Na-K ATP 酶是否存在于患有 原发性高血压比正常人对 Ca 的抑制更敏感 并确定纯化的蛋白质在这种情况下可能发挥什么作用 差异。