title: Spatial and Temporal Regulation of Receptor Tyrosine Kinase Activation and Intracellular Signal Transduction.
abstract: Epidermal growth factor (EGF) and insulin receptor tyrosine kinases (RTKs) exemplify how receptor location is coupled to signal transduction. Extracellular binding of ligands to these RTKs triggers their concentration into vesicles that bud off from the cell surface to generate intracellular signaling endosomes. On the exposed cytosolic surface of these endosomes, RTK autophosphorylation selects the downstream signaling proteins and lipids to effect growth factor and polypeptide hormone action. This selection is followed by the recruitment of protein tyrosine phosphatases that inactivate the RTKs and deliver them by membrane fusion and fission to late endosomes. Coincidentally, proteinases inside the endosome cleave the EGF and insulin ligands. Subsequent inward budding of the endosomal membrane generates multivesicular endosomes. Fusion with lysosomes then results in RTK degradation and downregulation. Through the spatial positioning of RTKs in target cells for EGF and insulin action, the temporal extent of signaling, attenuation, and downregulation is regulated.
authors.affiliation: Department of Medicine, McGill University Hospital Research Institute, Montreal, Quebec, Canada H4A 3J1; email: john.bergeron@mcgill.ca , sophie.dahan50@gmail.com , michel.dominguez.geeraerts@gmail.com , barry.posner@mcgill.ca.
authors.forename: John J M
authors.initials: JJ
authors.lastname: Bergeron
authors.affiliation: Department of Physiology and Pharmacology, Western University, London, Ontario, Canada N6A 5C1; email: john.diguglielmo@schulich.uwo.ca.
authors.forename: Gianni M
authors.initials: GM
authors.lastname: Di Guglielmo
authors.affiliation: Department of Medicine, McGill University Hospital Research Institute, Montreal, Quebec, Canada H4A 3J1; email: john.bergeron@mcgill.ca , sophie.dahan50@gmail.com , michel.dominguez.geeraerts@gmail.com , barry.posner@mcgill.ca.
authors.forename: Sophie
authors.initials: S
authors.lastname: Dahan
authors.affiliation: Department of Medicine, McGill University Hospital Research Institute, Montreal, Quebec, Canada H4A 3J1; email: john.bergeron@mcgill.ca , sophie.dahan50@gmail.com , michel.dominguez.geeraerts@gmail.com , barry.posner@mcgill.ca.
authors.forename: Michel
authors.initials: M
authors.lastname: Dominguez
authors.affiliation: Department of Medicine, McGill University Hospital Research Institute, Montreal, Quebec, Canada H4A 3J1; email: john.bergeron@mcgill.ca , sophie.dahan50@gmail.com , michel.dominguez.geeraerts@gmail.com , barry.posner@mcgill.ca.
authors.forename: Barry I
authors.initials: BI
authors.lastname: Posner
mesh_terms: D002462:Cell Membrane / Q000378:metabolism; D004705:Endocytosis; D011992:Endosomes / Q000378:metabolism; D004815:Epidermal Growth Factor / Q000235:genetics* / Q000378:metabolism; D066246:ErbB Receptors / Q000235:genetics* / Q000378:metabolism; D025461:Feedback, Physiological; D005786:Gene Expression Regulation; D006801:Humans; D007328:Insulin / Q000235:genetics* / Q000378:metabolism; D007425:Intracellular Membranes / Q000378:metabolism; D010766:Phosphorylation; D021381:Protein Transport; D017027:Protein Tyrosine Phosphatases / Q000235:genetics / Q000378:metabolism; D011505:Protein-Tyrosine Kinases / Q000235:genetics* / Q000378:metabolism; D015398:Signal Transduction
chemical_list: D007328:Insulin; D004815:Epidermal Growth Factor; C410467:insulin receptor tyrosine kinase; C512478:EGFR protein, human; D066246:ErbB Receptors; D011505:Protein-Tyrosine Kinases; D017027:Protein Tyrosine Phosphatases
keywords: EGF; insulin; ligand degradation; membrane trafficking; signaling endosome; signaling interactome