Terracio L, Simpson D G, Hilenski L, Carver W, Decker R S, Vinson N, Borg T K
Department of Anatomy, Cell Biology and Neurosciences, Northwestern University, School of Medicine, Chicago, Illinois 60611.
J Cell Physiol. 1990 Oct;145(1):78-87. doi: 10.1002/jcp.1041450112.
Vinculin is a major cytoskeletal component in striated muscle, where it has been reported to form a rib-like structure between the cell membrane and the Z-disk termed a costamere. This arrangement of vinculin has been purported to be involved in the alignment of the myofibrils. However, the three-dimensional arrangement of vinculin in relation to the Z-disk of the myofibril was not known. In the present study, we examined the distribution of vinculin in striated muscle with monospecific antibodies using immunofluorescence and laser scanning confocal microscopy. Isolated cardiac and skeletal muscle cells from a variety of species, tissue sections, and neonatal myocytes with developing myofibrils were examined. Optical sectioning in the X-Y and X-Z planes demonstrated that vinculin immunoreactivity was heaviest at the periphery of the cell; however, the immunoreactivity was also distributed within the Z-disk although at a relatively reduced level. This distribution is potentially significant in understanding the physiological significance of vinculin in striated muscle function and in myofibrillogenesis.
纽蛋白是横纹肌中的一种主要细胞骨架成分，据报道，它在细胞膜和Z盘之间形成一种称为肌小节的肋状结构。纽蛋白的这种排列据称参与了肌原纤维的排列。然而，纽蛋白相对于肌原纤维Z盘的三维排列尚不清楚。在本研究中，我们使用免疫荧光和激光扫描共聚焦显微镜，用单特异性抗体检测了横纹肌中纽蛋白的分布。我们检查了来自多种物种的分离的心肌和骨骼肌细胞、组织切片以及具有发育中肌原纤维的新生心肌细胞。在X-Y和X-Z平面上的光学切片显示，纽蛋白免疫反应性在细胞周边最重；然而，免疫反应性也分布在Z盘内，尽管水平相对较低。这种分布对于理解纽蛋白在横纹肌功能和肌原纤维形成中的生理意义可能具有重要意义。
