title: Phosphorylation of the common neurotrophin receptor p75 by p38beta2 kinase affects NF-kappaB and AP-1 activities.
abstract: The signaling pathways invoked by ligand binding to the common neurotrophin receptor p75NTR are incompletely understood. Using the yeast two-hybrid system, we identified the mitogen-activated protein (MAP) kinase p38beta2 as a specific interactor with the 5th and 6th alpha helices of the p75NTR intracytoplasmic region. The consequences of this interaction were studied, using primary cultures of Schwann cells and the 293T cell line. Phosphorylation of p75NTR by p38beta2 was induced in vitro and in vivo by MAP kinase kinases (MKK) 6 activation. This pathway demonstrated feedback in that nerve growth factor (NGF) binding increased p38beta2 activity, causing an increase of nuclear factor-kappaB (NF-kappaB) activation and a decrease of AP-1 activation. The mechanisms described explain at least in part why NGF binding to p75NTR increases cell survival in certain circumstances.
authors.affiliation: Program on Aging, The Burnham Institute, La Jolla, CA 92037, USA.
authors.forename: J J
authors.initials: JJ
authors.lastname: Wang
authors.forename: A
authors.initials: A
authors.lastname: Tasinato
authors.forename: D W
authors.initials: DW
authors.lastname: Ethell
authors.forename: M P
authors.initials: MP
authors.lastname: Testa
authors.forename: D E
authors.initials: DE
authors.lastname: Bredesen
mesh_terms: D000818:Animals; D017209:Apoptosis / Q000502:physiology*; D002470:Cell Survival / Q000187:drug effects / Q000502:physiology; D002478:Cells, Cultured / Q000187:drug effects / Q000378:metabolism; D019281:Dimerization; D006801:Humans; D020935:MAP Kinase Signaling System / Q000502:physiology*; D048290:Mitogen-Activated Protein Kinase 11; D020928:Mitogen-Activated Protein Kinases / Q000378:metabolism*; D016328:NF-kappa B / Q000378:metabolism*; D020932:Nerve Growth Factor / Q000494:pharmacology; D010766:Phosphorylation; D017434:Protein Structure, Tertiary / Q000502:physiology; D051381:Rats; D020800:Receptor, Nerve Growth Factor / Q000378:metabolism*; D012583:Schwann Cells / Q000187:drug effects / Q000378:metabolism; D018808:Transcription Factor AP-1 / Q000378:metabolism*; D015003:Yeasts / Q000378:metabolism
chemical_list: D016328:NF-kappa B; D020800:Receptor, Nerve Growth Factor; D018808:Transcription Factor AP-1; D020932:Nerve Growth Factor; D048290:Mitogen-Activated Protein Kinase 11; D020928:Mitogen-Activated Protein Kinases