title: The postsynaptic density protein PSD-95 differentially regulates insulin- and Src-mediated current modulation of mouse NMDA receptors expressed in Xenopus oocytes.
abstract: The NMDA subtype of glutamate receptor is physically associated with the postsynaptic density protein PSD-95 at glutamatergic synapses. The channel activity of NMDA receptors is regulated by different signaling molecules, including protein tyrosine kinases. Because previous results have suggested a role for protein kinase C (PKC) in insulin potentiation of NMDA currents in oocytes, the effects of coexpression of PSD-95 on insulin and PKC potentiation of NMDA currents from these receptors were compared. Another primary objective was to determine if PSD-95 could enable Src to potentiate currents from NR2A/NR1 and NR2B/NR1 receptors expressed in Xenopus oocytes. The results show opposite effects of PSD-95 coexpression on Src and insulin modulation of NR2A/NR1 receptor currents. Src potentiation of mouse NR2A/NR1 currents required PSD-95 coexpression. In contrast, PSD-95 coexpression eliminated insulin-mediated potentiation of NR2A/NR1 receptor currents. PSD-95 coexpression also eliminated PKC potentiation of NR2A/NR1 receptor currents. PSD-95 may therefore play a key role in controlling kinase modulation of NR2A/NR1 receptor currents at glutamatergic synapses.
authors.affiliation: Laboratories of Integrative Neuroscience and Molecular Biology, Department of Biological Sciences, University of Illinois at Chicago, Chicago, Illinois, USA.
authors.forename: G Y
authors.initials: GY
authors.lastname: Liao
authors.forename: M A
authors.initials: MA
authors.lastname: Kreitzer
authors.forename: B J
authors.initials: BJ
authors.lastname: Sweetman
authors.forename: J P
authors.initials: JP
authors.lastname: Leonard
mesh_terms: D000818:Animals; D000076122:Disks Large Homolog 4 Protein; D004553:Electric Conductivity; D005260:Female; D015870:Gene Expression; D051528:Guanylate Kinases; D006801:Humans; D007328:Insulin / Q000494:pharmacology*; D047908:Intracellular Signaling Peptides and Proteins; D008565:Membrane Proteins; D051379:Mice; D009419:Nerve Tissue Proteins / Q000235:genetics / Q000502:physiology*; D009865:Oocytes / Q000378:metabolism*; D011493:Protein Kinase C / Q000378:metabolism; D016194:Receptors, N-Methyl-D-Aspartate / Q000235:genetics / Q000502:physiology*; D014162:Transfection; D014981:Xenopus; D019061:src-Family Kinases / Q000502:physiology*
chemical_list: D000076122:Disks Large Homolog 4 Protein; C501447:Dlg4 protein, mouse; D007328:Insulin; D047908:Intracellular Signaling Peptides and Proteins; D008565:Membrane Proteins; D009419:Nerve Tissue Proteins; D016194:Receptors, N-Methyl-D-Aspartate; C033652:postsynaptic density proteins; D019061:src-Family Kinases; D011493:Protein Kinase C; D051528:Guanylate Kinases