The role of microfilaments in the capping of epidermal growth factor receptor in A431 cells.
Capping of the EGF receptor (EGF-R) on the surface of suspended and adherent epidermoid carcinoma cells, A431, is studied. It was induced at 20 degrees C after treating cells with monoclonal antibody to the EGF receptor followed by the second antibody conjugated with FITC. Accumulation of cortical actin under the caps was detected by rhodamine-phalloidin. Destruction of the actin stress-fiber-like bundles was observed during incubation of cells with the ligands at 0 degrees C. Two processes appear to take place at 20 degrees C: redistribution of the EGF-R with cortical actin into the caps within 15-30 min and reconstruction of cytoplasmic actin bundles over 45-60 min. Dihydrocytochalasin B prevented cap formation in adherent cells, but small patches of EGF-R colocalized with actin aggregates under plasma membrane were observed. The function of different actin-containing cytoskeleton structures in the process of capping is discussed.
Khrebtukova
I A
IA
Institute of Cytology, Academy of Sciences, Leningrad, USSR.
Kwiatkowska
K
K
Gudkova
D A
DA
Sorokin
A B
AB
Pinaev
G P
GP
D008841:Actin Cytoskeleton / Q000737:chemistry / Q000502:physiology* / Q000648:ultrastructure; D000199:Actins / Q000032:analysis / Q000502:physiology; D000911:Antibodies, Monoclonal / Q000276:immunology; D002294:Carcinoma, Squamous Cell / Q000473:pathology / Q000503:physiopathology / Q000648:ultrastructure; D002462:Cell Membrane / Q000737:chemistry / Q000187:drug effects / Q000648:ultrastructure; D003571:Cytochalasin B / Q000494:pharmacology; D066246:ErbB Receptors / Q000276:immunology / Q000502:physiology* / Q000648:ultrastructure; D016650:Fluorescein-5-isothiocyanate; D005452:Fluoresceins; D005455:Fluorescent Antibody Technique; D006801:Humans; D011940:Receptor Aggregation / Q000187:drug effects / Q000502:physiology*; D013861:Thiocyanates; D014407:Tumor Cells, Cultured / Q000473:pathology / Q000648:ultrastructure
D000199:Actins; D000911:Antibodies, Monoclonal; D005452:Fluoresceins; D013861:Thiocyanates; D003571:Cytochalasin B; D066246:ErbB Receptors; D016650:Fluorescein-5-isothiocyanate