TY - JOUR
T1 - Phosphorylation of AMPA-Type Glutamate Receptors by Calcium/ Calmodulin-Dependent Protein Kinase II and Protein Kinase C in Cultured Hippocampal Neurons
AU - Tan, Soon Eng
AU - Wenthold, Robert J.
AU - Soderling, Thomas R.
PY - 1994/3
Y1 - 1994/3
N2 - Phosphorylation of glutamate receptors (GluRs) is emerging as an important regulatory mechanism. In this study 32P la- beling of non-NMDA GluRs was investigated in cultured hippocampal neurons stimulated 2-15 min with agonists that selectively stimulate either Ca2+/calmodulin-dependent protein kinase II (CaM-kinase II), Ca2+/phospholipid-dependent protein kinase C (PKC), or cAMP-dependent protein kinase A (PKA). Treatment of hippocampal neurons with glutamate/ glycine (Glu/Gly), ionomycin, or 12-O-tetradecanoylphorbol 13-acetate (TPA) increased 32P labeling of immunoprecipitated α-amino-3-hydroxy-5-methyl-4-isoxazoleproprionate (AMPA)-type GluRs by 145%, 180%, and 227%, respectively, of control values. This increased phosphorylation of GluRs was predominantly 32P-Ser with little 32P-Thr and no detectable 32P-Tyr. Glu/Gly and ionomycin, but not TPA, also increased 32P labeling of CaM-kinase II by 175% and 195%, respectively, of control values. Of these three agonists, only TPA stimulated phosphorylation of MARCKS (225% of control), a specific substrate of PKC. Forskolin treatment gave a three- to fourfold increase in the active catalytic subunit of PKA but did not result in the 32P labeling of AMPA-type GluRs, CaM-kinase II, or MARCKS. Phosphorylation of GluRs in response to Glu/Gly was blocked by a specific NMDA receptor/ion channel antagonist (DL-2-amino-5-phosphon-ovaleric acid) or by a cell-permeable inhibitor of CaM-kinase II (1-[N,O-bis(1,5-isoquinolinesulfonyl)-N-methyl-L-tyrosyl]-4-phenylpiperazine, KN-62). These results are consistent with the hypothesis that Ca2+ influx through the NMDA-type ion channel can activate CaM-kinase II, which in turn can phosphorylate and regulate AMPA-type GluR ion channels (McGlade-McCulloh et al., 1993). Such a mechanism could contribute to the postsynaptic component of long-term potentiation and other forms of synaptic plasticity.
AB - Phosphorylation of glutamate receptors (GluRs) is emerging as an important regulatory mechanism. In this study 32P la- beling of non-NMDA GluRs was investigated in cultured hippocampal neurons stimulated 2-15 min with agonists that selectively stimulate either Ca2+/calmodulin-dependent protein kinase II (CaM-kinase II), Ca2+/phospholipid-dependent protein kinase C (PKC), or cAMP-dependent protein kinase A (PKA). Treatment of hippocampal neurons with glutamate/ glycine (Glu/Gly), ionomycin, or 12-O-tetradecanoylphorbol 13-acetate (TPA) increased 32P labeling of immunoprecipitated α-amino-3-hydroxy-5-methyl-4-isoxazoleproprionate (AMPA)-type GluRs by 145%, 180%, and 227%, respectively, of control values. This increased phosphorylation of GluRs was predominantly 32P-Ser with little 32P-Thr and no detectable 32P-Tyr. Glu/Gly and ionomycin, but not TPA, also increased 32P labeling of CaM-kinase II by 175% and 195%, respectively, of control values. Of these three agonists, only TPA stimulated phosphorylation of MARCKS (225% of control), a specific substrate of PKC. Forskolin treatment gave a three- to fourfold increase in the active catalytic subunit of PKA but did not result in the 32P labeling of AMPA-type GluRs, CaM-kinase II, or MARCKS. Phosphorylation of GluRs in response to Glu/Gly was blocked by a specific NMDA receptor/ion channel antagonist (DL-2-amino-5-phosphon-ovaleric acid) or by a cell-permeable inhibitor of CaM-kinase II (1-[N,O-bis(1,5-isoquinolinesulfonyl)-N-methyl-L-tyrosyl]-4-phenylpiperazine, KN-62). These results are consistent with the hypothesis that Ca2+ influx through the NMDA-type ion channel can activate CaM-kinase II, which in turn can phosphorylate and regulate AMPA-type GluR ion channels (McGlade-McCulloh et al., 1993). Such a mechanism could contribute to the postsynaptic component of long-term potentiation and other forms of synaptic plasticity.
KW - Calmodulin-kinase
KW - Glutamate receptor
KW - Hippocampus
KW - Protein kinase
KW - Synaptic plasticity
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UR - http://www.scopus.com/inward/citedby.url?scp=0028218266&partnerID=8YFLogxK
M3 - Article
C2 - 7509863
AN - SCOPUS:0028218266
SN - 0270-6474
VL - 14
SP - 1123
EP - 1129
JO - Journal of Neuroscience
JF - Journal of Neuroscience
IS - 3 I
ER -