期刊名称:Proceedings of the National Academy of Sciences
印刷版ISSN:0027-8424
电子版ISSN:1091-6490
出版年度:1980
卷号:77
期号:7
页码:4127-4131
DOI:10.1073/pnas.77.7.4127
语种:English
出版社:The National Academy of Sciences of the United States of America
摘要:As intracellular protein of 130,000 molecular weight was recently isolated in this laboratory from chicken gizzard smooth muscle. By immunofluorescence observations of cultured chicken fibroblasts, it was shown to be concentrated on the ventral surfaces of the cells where they formed focal adhesions to the substratum [Geiger, B. (1979) Cell 18, 193-205]. Focal adhesions are sites where, inside the fibroblast, microfilament bundles are known to terminate at the cell membrane. The suggestion was made that this new protein (herein named "vinculin") might be involved in the linkage of the termini of microfilament bundles to membranes in various cell types. To explore this possibility, in the present study we examined several chicken tissues, including intestinal epithelium, gizzard smooth muscle, and cardiac striated muscle, by immunoelectron microscopic labeling for vinculin on ultrathin frozen sections of the specimens. In each case, the immunolabeling for vinculin was concentrated close to membrane sites where microfilament bundles terminate: at the zonula adherens in the junctional complex of the brush border of epithelial cells; at the membrane-associated sense plaques of smooth cells; and at the fascia adherens of the intercalated disk membranes of cardiac muscle cells. These results suggest therefore that vinculin may participate in the anchoring of microfilament bundles to specific membrane sites in various cells.