title: A dominant role of the juxtamembrane region of the TrkA nerve growth factor receptor during neuronal cell differentiation.
abstract: All receptor tyrosine kinases share a common intracellular signaling machinery, including ras activation, whereas cellular responses vary from mitogenesis to cell differentiation. To investigate the structural basis for receptor tyrosine kinase action for nerve growth factor, the juxtamembrane region of TrkA was transferred to a corresponding region of the epidermal growth factor (EGF) receptor. The resulting chimeric receptor contains an additional Shc site, Tyr490, in the juxtamembrane region. In transfected PC12 cell lines, neuronal differentiation was observed with EGF treatment, as evidenced by increased neurite extension. The action of the chimeric receptor was correlated with prolonged activation of MAP kinases and a 3-4-fold increase in phosphatidylinositol 3-kinase activity. The effect of the juxtamembrane chimera was dependent upon the Shc site at Tyr490, because expression of a chimeric receptor containing a Y490F mutation resulted in a complete loss of neuritogenesis by EGF treatment. These findings indicate that the juxtamembrane region of the TrkA receptor serves as a key functional domain that can confer a dominant effect upon neuronal differentiation.
authors.affiliation: Beth Israel Deaconess Medical Center, Division of Signal Transduction, Department of Medicine, Boston, Massachusetts 02115, USA.
authors.forename: S O
authors.initials: SO
authors.lastname: Yoon
authors.forename: S P
authors.initials: SP
authors.lastname: Soltoff
authors.forename: M V
authors.initials: MV
authors.lastname: Chao
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001665:Binding Sites / Q000235:genetics; D017871:Calcium-Calmodulin-Dependent Protein Kinases / Q000378:metabolism; D002454:Cell Differentiation; D004815:Epidermal Growth Factor / Q000235:genetics / Q000378:metabolism / Q000494:pharmacology; D066246:ErbB Receptors / Q000235:genetics / Q000378:metabolism*; D008565:Membrane Proteins / Q000235:genetics / Q000378:metabolism; D009154:Mutation; D016501:Neurites / Q000502:physiology; D009474:Neurons / Q000166:cytology*; D016716:PC12 Cells; D010446:Peptide Fragments / Q000235:genetics / Q000378:metabolism*; D019869:Phosphatidylinositol 3-Kinases; D017853:Phosphotransferases (Alcohol Group Acceptor) / Q000378:metabolism; D011518:Proto-Oncogene Proteins / Q000235:genetics / Q000378:metabolism*; D051381:Rats; D020794:Receptor Protein-Tyrosine Kinases / Q000235:genetics / Q000378:metabolism*; D020917:Receptor, trkA; D017475:Receptors, Nerve Growth Factor / Q000235:genetics / Q000378:metabolism*; D011993:Recombinant Fusion Proteins / Q000378:metabolism; D015398:Signal Transduction
chemical_list: D008565:Membrane Proteins; D010446:Peptide Fragments; D011518:Proto-Oncogene Proteins; D017475:Receptors, Nerve Growth Factor; D011993:Recombinant Fusion Proteins; D004815:Epidermal Growth Factor; D019869:Phosphatidylinositol 3-Kinases; D017853:Phosphotransferases (Alcohol Group Acceptor); D066246:ErbB Receptors; D020794:Receptor Protein-Tyrosine Kinases; D020917:Receptor, trkA; D017871:Calcium-Calmodulin-Dependent Protein Kinases