| Abstract: | A rapid, new procedure for the isolation of intact tonofilaments from newborn rat skins is described. The filament preparations show two major protein subunits on SDS-PAGE with molecular weights of 58000 and 66000 D. An antiserum prepared against the 58000 D protein reacted specifically with the tonofilament preparation, but not with the protein subunits of neurofilaments, glial filaments, tubulin or actin. This specificity is confirmed by indirect immunofluorescence: anti-P58 reacts with the epidermis, whereas antisera against the neurofilament or glial filament proteins and anti-tubulin do not. These data suggest that epidermal filaments represent a class of intermediate filaments distinct from either glial filaments or neurofilaments. |
