Gangliosides Activate Trk Receptors by Inducing the Release of Neurotrophins

Autor: Stuart J. Rabin, Alessia Bachis, Italo Mocchetti
Rok vydání: 2002
Předmět:
Time Factors
Tropomyosin receptor kinase B
Tropomyosin receptor kinase A
Biochemistry
Tropomyosin receptor kinase C
Indole Alkaloids
Rats
Sprague-Dawley

Mice
chemistry.chemical_compound
Sphingosine
Neurotrophic factors
Cerebellum
Gangliosides
Low-affinity nerve growth factor receptor
Phosphorylation
Cells
Cultured

Neurons
biology
Chemistry
Autophosphorylation
3T3 Cells
Cell biology
embryonic structures
lipids (amino acids
peptides
and proteins)

Protein Binding
Signal Transduction
Neurotrophin
animal structures
Cell Survival
Carbazoles
Enzyme-Linked Immunosorbent Assay
G(M1) Ganglioside
Transfection
Cellular and Molecular Neuroscience
Animals
Nerve Growth Factors
Receptor
trkA

Molecular Biology
Dose-Response Relationship
Drug

Tyrosine phosphorylation
Cell Biology
Rats
carbohydrates (lipids)
enzymes and coenzymes (carbohydrates)
nervous system
Immunoglobulin G
Trk receptor
biology.protein
Tyrosine
Zdroj: Journal of Biological Chemistry. 277:49466-49472
ISSN: 0021-9258
DOI: 10.1074/jbc.m203240200
Popis: We used NIH-3T3 fibroblasts expressing the different Trk receptors to examine whether GM1 ganglioside and its semisynthetic derivative LIGA20 activate various neurotrophin receptors. GM1 induced autophosphorylation of TrkC more potently than TrkA or TrkB receptors. In contrast, LIGA20 activated TrkB tyrosine phosphorylation only. Therefore, Scatchard analysis was performed to determine whether GM1 binds to TrkC. GM1 failed to displace neurotrophin-3 binding, suggesting that this ganglioside does not act as a ligand for Trk receptors. In addition, GM1 failed to induce autophosphorylation of a chimeric receptor consisting of the extracellular domain of the tumor necrosis factor receptor and the intracellular domain of TrkA, suggesting that GM1 does not affect the tyrosine kinase domain. We next determined whether GM1 induces the release of neurotrophins from fibroblast cells. GM1 induced a rapid and significant increase in the amount of neurotrophin-3, but not other neurotrophins. This effect was independent of the presence of Trk because K252a did not prevent GM1-mediated release of neurotrophin-3. Moreover, GM1-mediated TrkC autophosphorylation was blocked by TrkC-IgG (but not TrkB-IgG) receptor bodies, further suggesting that GM1 activates TrkC by inducing the release of neurotrophin-3. This hypothesis was also tested in cultured cerebellar granule cells. GM1 induced neurotrophin-3 (but not brain-derived neurotrophic factor or nerve growth factor) release. In contrast, LIGA20 increased the secretion of brain-derived neurotrophic factor. Our data show that gangliosides may activate different Trk receptors by differentially affecting the release of neurotrophins.
Databáze: OpenAIRE