title: Cellular prion protein signaling in serotonergic neuronal cells.
abstract: The cellular prion protein PrP(C) is the normal counterpart of the scrapie prion protein PrP(Sc), the main component of the infectious agent of transmissible spongiform encephalopathies (TSEs). It is a ubiquitous cell-surface glycoprotein, abundantly expressed in neurons, which constitute the targets of TSE pathogenesis. Taking advantage of the 1C11 neuroectodermal cell line, endowed with the capacity to convert into 1C11(5-HT) serotonergic or 1C11(NE) noradrenergic neuronal cells, allowed us to ascribe a signaling function to PrP(C). Antibody-mediated ligation of PrP(C) recruits transduction pathways, which involve nicotinamide adenine dinucleotide phosphate (NADPH) oxidase-dependent reactive oxygen species production and target the extracellular-regulated kinases ERK1/2. In fully differentiated cells only, these effectors are under the control of a PrP(C)-caveolin-Fyn platform, located on neuritic extensions. In addition to its proper signaling activity, PrP(C) modulates the agonist-induced response of the three serotonergic G protein-coupled receptors present on the 1C11(5-HT) differentiated cells. The impact of PrP(C) ligation on the receptor couplings depends on the receptor subtype and the pathway considered. The implementation of the PrP(C)-caveolin complex again is mandatory for PrP(C) to exert its action on 5-HT receptor signaling. Our current data argue that PrP(C) interferes with the intensities and/or dynamics of G protein activation by agonist-bound 5-HT receptors. By mobilizing transduction cascades controlling the cellular redox state and the ERK1/2 kinases and by altering 5-HT receptor-mediated intracellular response, PrP(C) takes part in the homeostasis of serotonergic neuronal cells. These findings may have implications for future research aiming at understanding the fate of serotonergic neurons in prion diseases.
authors.affiliation: Différenciation cellulaire et prions, CNRS FRE 2937 7, rue Guy Moquet 94801 Villejuif, France. mouillet@vjf.cnrs.fr
authors.forename: Sophie
authors.initials: S
authors.lastname: Mouillet-Richard
authors.forename: Benoît
authors.initials: B
authors.lastname: Schneider
authors.forename: Elodie
authors.initials: E
authors.lastname: Pradines
authors.forename: Mathéa
authors.initials: M
authors.lastname: Pietri
authors.forename: Myriam
authors.initials: M
authors.lastname: Ermonval
authors.forename: Jacques
authors.initials: J
authors.lastname: Grassi
authors.forename: J Grayson
authors.initials: JG
authors.lastname: Richards
authors.forename: Vincent
authors.initials: V
authors.lastname: Mutel
authors.forename: Jean-Marie
authors.initials: JM
authors.lastname: Launay
authors.forename: Odile
authors.initials: O
authors.lastname: Kellermann
mesh_terms: D000818:Animals; D022461:Caveolins / Q000378:metabolism; D002454:Cell Differentiation; D002460:Cell Line; D004475:Ectoderm / Q000378:metabolism; D019204:GTP-Binding Proteins / Q000378:metabolism; D005786:Gene Expression Regulation; D006023:Glycoproteins / Q000378:metabolism; D051379:Mice; D019950:Mitogen-Activated Protein Kinase 1 / Q000378:metabolism; D048052:Mitogen-Activated Protein Kinase 3 / Q000378:metabolism; D008954:Models, Biological; D009474:Neurons / Q000378:metabolism*; D018621:PrPC Proteins / Q000378:metabolism*; D015398:Signal Transduction
chemical_list: D022461:Caveolins; D006023:Glycoproteins; D018621:PrPC Proteins; D019950:Mitogen-Activated Protein Kinase 1; D048052:Mitogen-Activated Protein Kinase 3; D019204:GTP-Binding Proteins