Represa A, Trabelsi-Terzidis H, Plantier M, Fattoum A, Jorquera I, Agassandian C, Ben-Ari Y, der Terrossian E
Université René Descartes, Paris V, France.
Exp Cell Res. 1995 Dec;221(2):333-43. doi: 10.1006/excr.1995.1383.
Caldesmon and calponin are two F-actin-binding and calcium-calmodulin-dependent proteins. In smooth muscle and nonmuscle cells both proteins are localized on actin filaments. Using one- or two-dimensional gel electrophoresis followed by the Western blot technique, and by immunofluorescence studies, we have given evidence that calponin is also present in rat and pig brain. In the present study, for the first time, we demonstrate caldesmon- and calponin-specific immunoreactivities in cerebellar cultured neurons. In the rat central nervous system these antibodies mainly stain neuronal cell bodies and dendrites. By confocal analysis we observed that calponin and caldesmon are located in the actomyosin domain although the total actin and myosin were not saturated. In many cases it is clear that these two proteins are adjacent rather than superimposed in the same domain of the cell. These results are compatible with the functional role of caldesmon and calponin in the regulation of the actomyosin activity as described by others and suggest that they are part of the contractile apparatus of neural cells.
钙调蛋白和钙结合蛋白是两种与F-肌动蛋白结合且依赖钙调蛋白的蛋白质。在平滑肌和非肌肉细胞中，这两种蛋白质都定位于肌动蛋白丝上。通过一维或二维凝胶电泳结合蛋白质印迹技术以及免疫荧光研究，我们已证实钙结合蛋白也存在于大鼠和猪的大脑中。在本研究中，我们首次在小脑培养神经元中证明了钙调蛋白和钙结合蛋白特异性免疫反应性。在大鼠中枢神经系统中，这些抗体主要染色神经元细胞体和树突。通过共聚焦分析，我们观察到尽管总肌动蛋白和肌球蛋白未饱和，但钙结合蛋白和钙调蛋白位于肌动球蛋白结构域中。在许多情况下，很明显这两种蛋白质在细胞的同一结构域中是相邻而非重叠的。这些结果与其他人描述的钙调蛋白和钙结合蛋白在调节肌动球蛋白活性中的功能作用相符，并表明它们是神经细胞收缩装置的一部分。
