Calmodulin activation of calcium-dependent sodium channels in excised membrane patches of Paramecium.
Calmodulin activation of calcium-dependent sodium channels in excised membrane patches of Paramecium.
复制标题
钙调素激活草履虫膜片中钙依赖性钠通道。
DOI：
10.1126/science.2169650
复制
发表时间：
1990
期刊：
影响因子：
--
通讯作者：
Ling,KY
中科院分区：
文献类型：
--
作者：
Saimi,Y;Ling,KY
钙调素是一种钙结合蛋白，参与钙信号的转导。草履虫钙调素突变体的电表型表明，该蛋白可能调节某些钙依赖性离子通道。钙依赖性钠单通道从草履虫的质膜切除补丁进行了鉴定，其活性被证明后，短暂暴露于亚微摩尔浓度的钙降低。通过向细胞质表面添加从草履虫中分离的钙调素，通道活性恢复到这些失活的斑块。这种通道活性的恢复不需要三磷酸腺苷，因此，可能是由于钙调蛋白的直接结合，无论是钠通道本身或通道调节器，与补丁膜。
Calmodulin is a calcium-binding protein that participates in the transduction of calcium signals. The electric phenotypes of calmodulin mutants ofParameciumhave suggested that the protein may regulate some calcium-dependent ion channels. Calcium-dependent sodium single channels in excised patches of the plasma membrane fromParameciumwere identified, and their activity was shown to decrease after brief exposure to submicromolar concentrations of calcium. Channel activity was restored to these inactivated patches by adding calmodulin that was isolated fromParameciumto the cytoplasmic surface. This restoration of channel activity did not require adenosine triphosphate and therefore, probably resulted from direct binding of calmodulin, either to the sodium channel itself or to a channel regulator that was associated with the patch membrane.