title: Keratin filaments of mouse epithelial cells are rapidly affected by epidermal growth factor.
abstract: The effects of epidermal growth factor (EGF) on the cytokeratin filaments of cultured murine epithelial cells were studied by the indirect immunofluorescence technique with affinity-purified antibodies. Mouse epithelial cells (MMC-E), grown on glass cover slips, and viewed by immunofluorescence microscopy, showed keratin-specific fluorescence as typical bright perinuclear aggregates corresponding to dense paracrystalline granules seen in electron microscopy. Within minutes after an exposure to EGF, the keratin granules in the MMC-E cells decreased. After 10 min of incubation, the cells had spread fibrillar keratin. Such an effect could not be found after a similar exposure to insulin, dexamethasone, dibutyryl cyclic AMP, or antimitotic drugs. EGF, therefore, has a relatively direct effect on the cytoskeletal organization of cultured epithelial cells. These rapid effects on the keratin filaments may explain the simultaneous EGF-induced ultrastructural surface changes of the cells. EGF may thus function as a regulatory factor in the migration of epithelial cells and in the mobility of their cell membranes. The epithelial cell line, MMC-E, should prove a useful model for studies on the action of EGF on nontransformed epithelial cells in vitro.
mesh_terms: D000818:Animals; D003994:Bucladesine / Q000494:pharmacology; D002460:Cell Line; D003571:Cytochalasin B / Q000494:pharmacology; D003599:Cytoskeleton / Q000187:drug effects* / Q000648:ultrastructure; D003907:Dexamethasone / Q000494:pharmacology; D004815:Epidermal Growth Factor / Q000494:pharmacology*; D007328:Insulin / Q000494:pharmacology; D007633:Keratins / Q000032:analysis*; D051379:Mice
chemical_list: D007328:Insulin; D003571:Cytochalasin B; D004815:Epidermal Growth Factor; D003994:Bucladesine; D007633:Keratins; D003907:Dexamethasone