Open AccessShc Proteins Are Localized on Endoplasmic Reticulum Membranes and Are Redistributed after Tyrosine Kinase Receptor Activation
Author(s) -
Lavinia Vittoria Lotti,
Luisa Lanfrancone,
Enrica Migliaccio,
Claudia Zompetta,
Giuliana Pelicci,
Anna Elisabetta Salcini,
Brunangelo Falini,
Pier Giuseppe Pelicci,
Maria Rosaria Torrisi
Publication year - 1996
Publication title -
molecular and cellular biology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.14
H-Index - 327
eISSN - 1067-8824
pISSN - 0270-7306
DOI - 10.1128/mcb.16.5.1946
Subject(s) - endoplasmic reticulum , microbiology and biotechnology , biology , endosome , endocytic cycle , autophosphorylation , immunoelectron microscopy , receptor tyrosine kinase , tyrosine kinase , phosphorylation , protein kinase a , endocytosis , signal transduction , biochemistry , intracellular , receptor , immunohistochemistry , immunology
The intracellular localization of Shc proteins was analyzed by immunofluorescence and immunoelectron microscopy in normal cells and cells expressing the epidermal growth factor receptor or the EGFR/erbB2 chimera. In unstimulated cells, the immunolabeling was localized in the central perinuclear area of the cell and mostly associated with the cytosolic side of rough endoplasmic reticulum membranes. Upon epidermal growth factor treatment and receptor tyrosine kinase activation, the immunolabeling became peripheral and was found to be associated with the cytosolic surface of the plasma membrane and endocytic structures, such as coated pits and endosomes, and with the peripheral cytosol. Receptor activation in cells expressing phosphorylation-defective mutants of Shc and erbB-2 kinase showed that receptor autophosphorylation, but not Shc phosphorylation, is required for redistribution of Shc proteins. The rough endoplasmic reticulum localization of Shc proteins in unstimulated cells and their massive recruitment to the plasma membrane, endocytic structures, and peripheral cytosol following receptor tyrosine kinase activation could account for multiple putative functions of the adaptor protein.