Glutamate activates protein kinase B (PKB/Akt) through AMPA receptors in cultured Bergmann glia cells.
Glutamate is involved in gene expression regulation in neurons and glial cells through the activation of a diverse array of signaling cascades. In Bergmann glia, Ca2+ -permeable alpha-hydroxy-5-methyl-4-isoazole-propionic acid (AMPA) receptors become tyrosine phosphorylated after ligand binding and by these means form multiprotein signaling complexes. Of the various proteins that associate to these receptors, the phosphatidylinositol 3-kinase (PI-3K) deserves special attention since D3-phosphorylated phosphoinositides are docking molecules for signaling proteins with a pleckstrin homology domain. In order to characterize the role of PI-3K in AMPA receptors signaling, in the present report we analyze the involvement of the serine/threonine protein kinase B in this process. Our results demonstrate an augmentation in protein kinase B phosphorylation and activity after glutamate exposure. Interestingly, the effect is independent of Ca2+ influx, but sensitive to Src blockers. Our present findings broaden our current knowledge of glial glutamate receptors signaling and their involvement glutamatergic neurotransmission.
Morales
Moisés
M
Departamento de Genética y Biología Molecular, Cinvestav-Zacatenco, México , DF, México.
González-Mejía
Martha E
ME
Bernabé
Alfonso
A
Hernández-Kelly
Luisa C R
LC
Ortega
Arturo
A
D000818:Animals; D002478:Cells, Cultured; D002642:Chick Embryo; D004789:Enzyme Activation; D018698:Glutamic Acid / Q000494:pharmacology / Q000502:physiology*; D038362:Glycogen Synthase Kinase 3 / Q000378:metabolism; D000071679:Glycogen Synthase Kinase 3 beta; D009457:Neuroglia / Q000166:cytology / Q000378:metabolism*; D019869:Phosphatidylinositol 3-Kinases / Q000378:metabolism; D010766:Phosphorylation; D051057:Proto-Oncogene Proteins c-akt / Q000378:metabolism*; D018091:Receptors, AMPA / Q000502:physiology*; D015398:Signal Transduction
D018091:Receptors, AMPA; D018698:Glutamic Acid; D019869:Phosphatidylinositol 3-Kinases; D000071679:Glycogen Synthase Kinase 3 beta; D051057:Proto-Oncogene Proteins c-akt; D038362:Glycogen Synthase Kinase 3