title: beta-Arrestin 2-mediated heterologous desensitization of IGF-IR by prolonged exposure of SH-SY5Y neuroblastoma cells to a mu opioid agonist.
abstract: Prolonged (12h) exposure of SH-SY5Y neuroblastoma cells to the mu-opioid receptor (MOPr) agonist [D-Ala(2),N-Me-Phe(4),Gly(5)-ol]-enkephalin (DAMGO) causes homologous desensitization as well as heterologous desensitization of the extracellular signal-regulated kinase 1/2 (ERK 1/2) phosphorylation induced by insulin-like growth factor (IGF)-I. Brief (15 min) but not prolonged exposure to DAMGO transregulates the insulin-like growth factor-I (IGF-I) receptor, as evidenced by its phosphorylation in the absence of IGF-I. Silencing of beta-arrestin 2 uncouples the crosstalk between the two receptors, thus maintaining IGF-I-mediated receptor phosphorylation and ERK 1/2 activation even after prolonged DAMGO exposure. Furthermore, MOPr-induced activation of IGF-I receptor requires the tyrosine kinase c-Src.
authors.affiliation: Department of Pharmacology, University of Bologna, Irnerio 48, 40126 Bologna, Italy.
authors.forename: Antonino
authors.initials: A
authors.lastname: Spartà
authors.forename: Monica
authors.initials: M
authors.lastname: Baiula
authors.forename: Gayle
authors.initials: G
authors.lastname: Campbell
authors.forename: Santi
authors.initials: S
authors.lastname: Spampinato
mesh_terms: D019390:Arrestins / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism*; D045744:Cell Line, Tumor; D020875:Enkephalin, Ala(2)-MePhe(4)-Gly(5)- / Q000494:pharmacology; D006801:Humans; D019950:Mitogen-Activated Protein Kinase 1 / Q000378:metabolism; D048052:Mitogen-Activated Protein Kinase 3 / Q000378:metabolism; D009447:Neuroblastoma / Q000235:genetics / Q000378:metabolism*; D010766:Phosphorylation; D034741:RNA, Small Interfering / Q000235:genetics; D020239:Receptor Cross-Talk; D017526:Receptor, IGF Type 1 / Q000235:genetics / Q000378:metabolism*; D017450:Receptors, Opioid, mu / Q000819:agonists*; D015398:Signal Transduction; D015533:Transcriptional Activation / Q000187:drug effects; D000071560:beta-Arrestin 2; D000071557:beta-Arrestins
chemical_list: C000605254:ARRB2 protein, human; D019390:Arrestins; D034741:RNA, Small Interfering; D017450:Receptors, Opioid, mu; D000071560:beta-Arrestin 2; D000071557:beta-Arrestins; D020875:Enkephalin, Ala(2)-MePhe(4)-Gly(5)-; D017526:Receptor, IGF Type 1; D019950:Mitogen-Activated Protein Kinase 1; D048052:Mitogen-Activated Protein Kinase 3