Notch activation induces neurite remodeling and functional modifications in SH-SY5Y neuronal cells.
Notch proteins are definitely recognized as key regulators of the neuronal fate during embryo development, but their function in the adult brain is still largely unknown. We have previously demonstrated that Notch pathway stimulation increases microtubules stability followed by the remodeling of neuronal morphology with neurite varicosities loss, thicker neuritis, and enlarged growth cones. Here we show that the neurite remodeling is a dynamic event, dependent on transcription and translation, and with functional implications. Exposure of differentiated human SH-SY5Y neuroblastoma cells to the Notch ligand Jagged1 induces varicosities loss all along the neurites, accompanied by the redistribution of presynaptic vesicles and the decrease in neurotransmitters release. As evaluated by time lapse digital imaging, dynamic changes in neurite morphology were rapidly reversible and dependent on the activation of the Notch signaling pathway. In fact, it was prevented by the inhibition of the proteolytic gamma-secretase enzyme or the transcription machinery, and was mimicked by the transfection of the intracellular domain of Notch. One hour after treatment with Jagged1, several genes were downregulated. Many of these genes encode proteins that are known to be involved in protein synthesis. These data suggest that in adult neurons, Notch pathway activates a transcriptional program that regulates the equilibrium between varicosities formation and varicosities loss in the neuronal presynaptic compartment involving the expression and redistribution of both structural and functional proteins.
Ferrari-Toninelli
Giulia
G
Department of Biomedical Sciences and Biotechnologies, and National Institute of Neuroscience - Italy, University of Brescia, Brescia, Italy.
Bonini
Sara Anna
SA
Uberti
Daniela
D
Napolitano
Francesco
F
Stante
Maria
M
Santoro
Federica
F
Minopoli
Giuseppina
G
Zambrano
Nicola
N
Russo
Tommaso
T
Memo
Maurizio
M
D000199:Actins / Q000235:genetics / Q000378:metabolism; D000704:Analysis of Variance; D002135:Calcium-Binding Proteins / Q000494:pharmacology; D002454:Cell Differentiation / Q000187:drug effects / Q000502:physiology*; D002461:Cell Line, Transformed; D003609:Dactinomycin / Q000494:pharmacology; D004791:Enzyme Inhibitors / Q000494:pharmacology; D020869:Gene Expression Profiling / Q000379:methods; D049452:Green Fluorescent Proteins / Q000235:genetics; D006801:Humans; D051819:Immunoglobulin J Recombination Signal Sequence-Binding Protein / Q000378:metabolism; D036341:Intercellular Signaling Peptides and Proteins / Q000494:pharmacology; D000072100:Jagged-1 Protein; D008565:Membrane Proteins / Q000494:pharmacology; D046228:Microarray Analysis / Q000379:methods; D008869:Microtubule-Associated Proteins; D016501:Neurites / Q000187:drug effects / Q000502:physiology*; D009447:Neuroblastoma / Q000473:pathology; D009474:Neurons / Q000166:cytology* / Q000187:drug effects; D009638:Norepinephrine / Q000378:metabolism; D011500:Protein Synthesis Inhibitors / Q000494:pharmacology; D051881:Receptor, Notch1 / Q000235:genetics / Q000378:metabolism*; D000072099:Serrate-Jagged Proteins; D015398:Signal Transduction / Q000502:physiology; D016704:Synapsins / Q000235:genetics / Q000378:metabolism; D013997:Time Factors; D014162:Transfection; D014404:Tubulin / Q000235:genetics / Q000378:metabolism
D000199:Actins; D002135:Calcium-Binding Proteins; D004791:Enzyme Inhibitors; D051819:Immunoglobulin J Recombination Signal Sequence-Binding Protein; D036341:Intercellular Signaling Peptides and Proteins; C000606273:JAG1 protein, human; D000072100:Jagged-1 Protein; D008565:Membrane Proteins; D008869:Microtubule-Associated Proteins; D011500:Protein Synthesis Inhibitors; C497570:RBPJ protein, human; D051881:Receptor, Notch1; D000072099:Serrate-Jagged Proteins; D016704:Synapsins; C503569:TBCEL protein, human; C498585:TUBB3 protein, human; D014404:Tubulin; D049452:Green Fluorescent Proteins; D003609:Dactinomycin; D009638:Norepinephrine