title: BDNF binding to truncated trkB.T1 does not affect gene expression.
abstract: Truncated trkB.T1 is a splice variant of the neurotrophin receptor trkB. In spite of its abundance, and ability to bind and internalize BDNF, it is not clear whether it can transmit BDNF signaling. We tested this hypothesis by searching for proteins binding the evolutionarily conserved cyto-domain of trkB.T1, and by studying BDNF-induced changes of gene expression through DNA microarrays. Cells bearing trkB.T1 receptors presented morphological changes. However, no cytoplasmic interactors of trkB.T1 were found. In addition, BDNF-dependent modulation of gene expression was detected in cells bearing trkB.TK but not trkB.T1 receptors. These results suggest that the main function of trkB.T1 is to regulate local availability of neurotrophins and that it is unable to sense changes in BDNF availability.
authors.affiliation: FIRC Institute for Molecular Oncology, Milano, Italy.
authors.forename: Nina
authors.initials: N
authors.lastname: Offenhäuser
authors.forename: Valeria
authors.initials: V
authors.lastname: Muzio
authors.forename: Stefano
authors.initials: S
authors.lastname: Biffo
mesh_terms: D016475:3T3 Cells; D017398:Alternative Splicing / Q000187:drug effects / Q000502:physiology; D000818:Animals; D019208:Brain-Derived Neurotrophic Factor / Q000494:pharmacology*; D048429:Cell Size / Q000187:drug effects / Q000502:physiology; D004705:Endocytosis / Q000187:drug effects / Q000502:physiology; D015870:Gene Expression / Q000187:drug effects / Q000502:physiology; D005796:Genes / Q000187:drug effects / Q000502:physiology; D051379:Mice; D009420:Nervous System / Q000187:drug effects / Q000254:growth & development* / Q000378:metabolism; D009422:Nervous System Diseases / Q000188:drug therapy*; D009473:Neuronal Plasticity / Q000187:drug effects* / Q000502:physiology; D009474:Neurons / Q000187:drug effects* / Q000378:metabolism; D018696:Neuroprotective Agents / Q000494:pharmacology*; D011485:Protein Binding / Q000187:drug effects / Q000502:physiology; D020033:Protein Isoforms / Q000187:drug effects / Q000235:genetics / Q000378:metabolism; D017434:Protein Structure, Tertiary / Q000187:drug effects / Q000502:physiology; D012333:RNA, Messenger / Q000187:drug effects / Q000378:metabolism; D020813:Receptor, trkB / Q000187:drug effects* / Q000235:genetics / Q000378:metabolism; D011956:Receptors, Cell Surface / Q000187:drug effects / Q000235:genetics / Q000378:metabolism; D015398:Signal Transduction / Q000187:drug effects / Q000502:physiology; D014158:Transcription, Genetic / Q000187:drug effects / Q000502:physiology; D014161:Transduction, Genetic
chemical_list: D019208:Brain-Derived Neurotrophic Factor; D018696:Neuroprotective Agents; D020033:Protein Isoforms; D012333:RNA, Messenger; D011956:Receptors, Cell Surface; D020813:Receptor, trkB