Mechanism and regulation of calcium/calmodulin-dependent protein kinase II targeting to the NR2B subunit of the N-methyl-D-aspartate receptor.
Calcium influx through the N-methyl-d-aspartate (NMDA)-type glutamate receptor and activation of calcium/calmodulin-dependent kinase II (CaMKII) are critical events in certain forms of synaptic plasticity. We have previously shown that autophosphorylation of CaMKII induces high-affinity binding to the NR2B subunit of the NMDA receptor (Strack, S., and Colbran, R. J. (1998) J. Biol. Chem. 273, 20689-20692). Here, we show that residues 1290-1309 in the cytosolic tail of NR2B are critical for CaMKII binding and identify by site-directed mutagenesis several key residues (Lys(1292), Leu(1298), Arg(1299), Arg(1300), Gln(1301), and Ser(1303)). Phosphorylation of NR2B at Ser(1303) by CaMKII inhibits binding and promotes slow dissociation of preformed CaMKII.NR2B complexes. Peptide competition studies imply a role for the CaMKII catalytic domain, but not the substrate-binding pocket, in the association with NR2B. However, analysis of monomeric CaMKII mutants indicates that the holoenzyme structure may also be important for stable association with NR2B. Residues 1260-1316 of NR2B are sufficient to direct the subcellular localization of CaMKII in intact cells and to confer dynamic regulation by calcium influx. Furthermore, mutation of residues in the CaMKII-binding domain in full-length NR2B bidirectionally modulates colocalization with CaMKII after NMDA receptor activation, suggesting a dynamic model for the translocation of CaMKII to postsynaptic targets.
Strack
S
S
Department of Molecular Physiology and Biophysics and the Center for Molecular Neuroscience, Vanderbilt University Medical Center, Nashville, Tennessee 37232-0615, USA.
McNeill
R B
RB
Colbran
R J
RJ
D000595:Amino Acid Sequence; D000818:Animals; D001665:Binding Sites; D001667:Binding, Competitive; D054732:Calcium-Calmodulin-Dependent Protein Kinase Type 2; D017871:Calcium-Calmodulin-Dependent Protein Kinases / Q000302:isolation & purification / Q000378:metabolism*; D002451:Cell Compartmentation; D020035:Holoenzymes / Q000378:metabolism; D036341:Intercellular Signaling Peptides and Proteins; D007527:Isoenzymes / Q000378:metabolism; D051379:Mice; D008969:Molecular Sequence Data; D010446:Peptide Fragments / Q000378:metabolism; D010455:Peptides / Q000494:pharmacology; D010750:Phosphoproteins / Q000378:metabolism; D010766:Phosphorylation; D011485:Protein Binding; D020836:Protein Structure, Quaternary; D016194:Receptors, N-Methyl-D-Aspartate / Q000302:isolation & purification / Q000378:metabolism*; D013569:Synapses
D020035:Holoenzymes; D036341:Intercellular Signaling Peptides and Proteins; D007527:Isoenzymes; C121001:NR2B NMDA receptor; D010446:Peptide Fragments; D010455:Peptides; D010750:Phosphoproteins; D016194:Receptors, N-Methyl-D-Aspartate; C085903:autocamtide-2; C063391:syntide-2; D054732:Calcium-Calmodulin-Dependent Protein Kinase Type 2; D017871:Calcium-Calmodulin-Dependent Protein Kinases