Gabbiani G, Schmid E, Winter S, Chaponnier C, de Ckhastonay C, Vandekerckhove J, Weber K, Franke W W
Proc Natl Acad Sci U S A. 1981 Jan;78(1):298-302. doi: 10.1073/pnas.78.1.298.
Smooth muscle cells of the digestive, respiratory, and urogenital tracts contain desmin as their major, if not exclusive, intermediate-size filament constituent and also show a predominance of gamma-type smooth muscle actin. We have now examined smooth muscle tissue of different blood vessels (e.g., aorta, small arteries, arterioles, venules, and vena cava) from various mammals (man, cow, pig, rabbit, rat) by one- and two-dimensional gel electrophoresis of cell proteins and by immunofluorescence microscopy using antibodies to different intermediate-sized filament proteins. Intermediate-sized filaments of vascular smooth muscle cells contain abundant amounts of vimentin and little, if any, desmin. On gel electrophoresis, vascular smooth muscle vimentin appears as two isoelectric variants of apparent pI values of 5.30 and 5.29, shows the characteristic series of proteolytic fragments, and is one of the major cell proteins. Thus vimentin has been demonstrated in a smooth muscle cell present in the body. Vascular smooth muscle cells are also distinguished by the predominance of a smooth muscle-specific alpha-type actin, whereas gamma-type smooth muscle actin is present only as a minor component. It is proposed that the intermediate filament and actin composition of vascular smooth muscle cells reflects a differentiation pathway separate from that of other smooth muscle cells and may be related to special functions and pathological disorders of blood vessels.
消化、呼吸和泌尿生殖道的平滑肌细胞含有结蛋白,作为其主要的(即便不是唯一的)中等大小的丝状成分,并且还显示出γ型平滑肌肌动蛋白占优势。我们现在通过细胞蛋白的一维和二维凝胶电泳以及使用针对不同中等大小丝状蛋白的抗体进行免疫荧光显微镜检查,研究了来自各种哺乳动物(人、牛、猪、兔、大鼠)的不同血管(如主动脉、小动脉、微动脉、微静脉和腔静脉)的平滑肌组织。血管平滑肌细胞的中等大小丝状成分含有大量波形蛋白,结蛋白含量很少(如果有的话)。在凝胶电泳上,血管平滑肌波形蛋白表现为表观等电点值为5.30和5.29的两种等电变体,显示出特征性的一系列蛋白水解片段,并且是主要的细胞蛋白之一。因此,波形蛋白已在体内存在的平滑肌细胞中得到证实。血管平滑肌细胞的另一个特点是平滑肌特异性α型肌动蛋白占优势,而γ型平滑肌肌动蛋白仅作为次要成分存在。有人提出,血管平滑肌细胞的中间丝和肌动蛋白组成反映了一条与其他平滑肌细胞不同的分化途径,并且可能与血管的特殊功能和病理紊乱有关。