Abstract
The ultrastructural localization of alpha-actinin and vinculin in chicken cardiac muscle was studied by double indirect immunoelectron microscopy, using ferritin and iron-dextran (Imposil) as the electron-dense markers conjugated to the secondary antibodies, on ultrathin frozen sections of fixed tissue. Fixation and immunolabeling procedures were developed that permitted maximal retention of the two proteins at their natural sites as well as their adequate labeling. alpha-Actinin was found both on the Z-bands, as expected, and near the fascia adherens of the intercalated discs, whereas vinculin was confined to the latter sites. At the fascia adherens, the double labeling results clearly showed that vinculin was situated closer to the membrane than was alpha-actinin. These results, coupled with earlier observations, suggest that vinculin may participate in the linkage of actin-containing microfilament bundles to membranes in a variety of cell types.
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- Dutton A. H., Tokuyasu K. T., Singer S. J. Iron-dextran antibody conjugates: General method for simultaneous staining of two components in high-resolution immunoelectron microscopy. Proc Natl Acad Sci U S A. 1979 Jul;76(7):3392–3396. doi: 10.1073/pnas.76.7.3392. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Geiger B. A 130K protein from chicken gizzard: its localization at the termini of microfilament bundles in cultured chicken cells. Cell. 1979 Sep;18(1):193–205. doi: 10.1016/0092-8674(79)90368-4. [DOI] [PubMed] [Google Scholar]
- Geiger B., Tokuyasu K. T., Dutton A. H., Singer S. J. Vinculin, an intracellular protein localized at specialized sites where microfilament bundles terminate at cell membranes. Proc Natl Acad Sci U S A. 1980 Jul;77(7):4127–4131. doi: 10.1073/pnas.77.7.4127. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Geiger B., Tokuyasu K. T., Singer S. J. Immunocytochemical localization of alpha-actinin in intestinal epithelial cells. Proc Natl Acad Sci U S A. 1979 Jun;76(6):2833–2837. doi: 10.1073/pnas.76.6.2833. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Masaki T., Endo M., Ebashi S. Localization of 6S component of a alpha-actinin at Z-band. J Biochem. 1967 Nov;62(5):630–632. doi: 10.1093/oxfordjournals.jbchem.a128717. [DOI] [PubMed] [Google Scholar]
- Mooseker M. S., Tilney L. G. Organization of an actin filament-membrane complex. Filament polarity and membrane attachment in the microvilli of intestinal epithelial cells. J Cell Biol. 1975 Dec;67(3):725–743. doi: 10.1083/jcb.67.3.725. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Tokuyasu K. T. A technique for ultracryotomy of cell suspensions and tissues. J Cell Biol. 1973 May;57(2):551–565. doi: 10.1083/jcb.57.2.551. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Tokuyasu K. T., Singer S. J. Improved procedures for immunoferritin labeling of ultrathin frozen sections. J Cell Biol. 1976 Dec;71(3):894–906. doi: 10.1083/jcb.71.3.894. [DOI] [PMC free article] [PubMed] [Google Scholar]