title: Regulation of epidermal growth factor receptor internalization by G protein-coupled receptors.
abstract: The epidermal growth factor (EGF) receptor (EGFR) plays a central role in regulating cell proliferation, differentiation, and migration. Cellular responses to EGF are dependent upon the amount of EGFR present on the cell surface. Stimulation with EGF induces sequestration of the receptor from the plasma membrane and its subsequent downregulation. Recently, internalization of the EGFR was also shown to be required for mitogenic signaling via the activation of MAP kinases. Therefore, mechanisms regulating internalization of the EGFR represent an important facet for the control of cellular response. Here, we demonstrate that EGFR is removed from the cell surface not only following stimulation with EGF, but also in response to stimulation of G protein-coupled lysophosphatidic acid (LPA) and beta2 adrenergic (beta2AR) receptors. Using a FLAG epitope-tagged EGFR to quantitate receptor internalization, we show that incubation with EGF, LPA, or isoproterenol (ISO) causes the time-dependent loss of cell surface EGFR. Internalization of EGFR by these ligands involves the tyrosine kinase activity of the receptor itself and c-Src, as well as the GTPase activity of dynamin. Unexpectedly, we find that internalization of the EGFR by EGF is dependent upon Gbetagamma and beta-arrestin proteins; expression of minigenes encoding the carboxyl terminii of the G protein-coupled receptor kinase 2, or beta-arrestin1, attenuates LPA-, ISO-, and EGF-mediated internalization of EGFR. Thus, G protein-coupled receptors can control the function of the EGFR by regulating its endocytosis.
authors.affiliation: Department of Surgery, Duke University Medical Center, Durham North Carolina 27710, USA.
authors.forename: Jihee
authors.initials: J
authors.lastname: Kim
authors.forename: Seungkirl
authors.initials: S
authors.lastname: Ahn
authors.forename: Rishu
authors.initials: R
authors.lastname: Guo
authors.forename: Yehia
authors.initials: Y
authors.lastname: Daaka
mesh_terms: D019390:Arrestins / Q000502:physiology; D000081247:CSK Tyrosine-Protein Kinase; D002460:Cell Line; D034281:Dynamins / Q000502:physiology; D004705:Endocytosis / Q000187:drug effects / Q000502:physiology*; D066246:ErbB Receptors / Q000378:metabolism*; D044387:GTP-Binding Protein beta Subunits; D044388:GTP-Binding Protein gamma Subunits; D020962:Heterotrimeric GTP-Binding Proteins / Q000378:metabolism / Q000502:physiology*; D006801:Humans; D007545:Isoproterenol / Q000494:pharmacology; D008246:Lysophospholipids / Q000502:physiology; D009842:Oligopeptides / Q000378:metabolism; D010446:Peptide Fragments / Q000502:physiology; D010455:Peptides / Q000378:metabolism; D020033:Protein Isoforms / Q000502:physiology; D011505:Protein-Tyrosine Kinases / Q000502:physiology; D011956:Receptors, Cell Surface / Q000819:agonists / Q000037:antagonists & inhibitors / Q000502:physiology*; D000071557:beta-Arrestins; D019061:src-Family Kinases
chemical_list: D019390:Arrestins; C118981:G-protein Beta gamma; D044387:GTP-Binding Protein beta Subunits; D044388:GTP-Binding Protein gamma Subunits; D008246:Lysophospholipids; D009842:Oligopeptides; D010446:Peptide Fragments; D010455:Peptides; D020033:Protein Isoforms; D011956:Receptors, Cell Surface; D000071557:beta-Arrestins; C085706:FLAG peptide; D066246:ErbB Receptors; D011505:Protein-Tyrosine Kinases; D000081247:CSK Tyrosine-Protein Kinase; D019061:src-Family Kinases; C000631346:CSK protein, human; D020962:Heterotrimeric GTP-Binding Proteins; D034281:Dynamins; D007545:Isoproterenol