CaMKII triggers the diffusional trapping of surface AMPARs through phosphorylation of stargazin.

Publication Type:

Journal Article

Authors:

Opazo, Patricio; Labrecque, Simon; Tigaret, Cezar M; Frouin, Arnaud; Wiseman, Paul W; Paul De Koninck; Choquet, Daniel

Source:

Neuron, Volume 67, Issue 2, p.239-52 (2010)

Keywords:

Action Potentials, Animals, Animals, Newborn, Benzothiadiazines, Benzylamines, Calcium, Calcium Channels, Calcium-Calmodulin-Dependent Protein Kinase Type 2, Cells, Cultured, Diffusion, Electric Stimulation, Embryo, Mammalian, Enzyme Activation, Excitatory Postsynaptic Potentials, Green Fluorescent Proteins, Hippocampus, Intracellular Signaling Peptides and Proteins, Membrane Proteins, Models, Biological, Neurons, Phosphorylation, Protein Kinase Inhibitors, Protein Transport, Rats, Rats, Sprague-Dawley, Receptors, AMPA, Statistics, Nonparametric, Sulfonamides, Transfection

Abstract:

<p>The Ca(2+)/calmodulin-dependent protein kinase II (CaMKII) is critically required for the synaptic recruitment of AMPA-type glutamate receptors (AMPARs) during both development and plasticity. However, the underlying mechanism is unknown. Using single-particle tracking of AMPARs, we show that CaMKII activation and postsynaptic translocation induce the synaptic trapping of AMPARs diffusing in the membrane. AMPAR immobilization requires both phosphorylation of the auxiliary subunit Stargazin and its binding to PDZ domain scaffolds. It does not depend on the PDZ binding domain of GluA1 AMPAR subunit nor its phosphorylation at Ser831. Finally, CaMKII-dependent AMPAR immobilization regulates short-term plasticity. Thus, NMDA-dependent Ca(2+) influx in the post-synapse triggers a CaMKII- and Stargazin-dependent decrease in AMPAR diffusional exchange at synapses that controls synaptic function.</p>