CaMKII Triggers the Diffusional Trapping of Surface AMPARs through Phosphorylation of Stargazin

• DOI: 10.1016/j.neuron.2010.06.007
• Publication Date: 2010-07-29T10:39:02Z
• Authors: Patricio Opazo; Simon Labrecque; Cezar M. Tigaret; Arnaud Frouin; Paul W. Wiseman; Paul De Koninck; Daniel Choquet
• Keywords: 0301 basic medicine; Benzylamines; Neuroscience(all); Green Fluorescent Proteins; Action Potentials; Benzothiadiazines; Hippocampus; Models, Biological; MOLNEURO; Diffusion; 03 medical and health sciences; Animals; Cells, Cultured; Intracellular Signaling Peptides and Proteins; Excitatory Postsynaptic Potentials; Membrane Proteins; Embryo, Mammalian; Electric Stimulation; Enzyme Activation; Animals, Newborn; SIGNALING; Calcium; Calcium Channels; Calcium-Calmodulin-Dependent Protein Kinase Type 2; Disks Large Homolog 4 Protein

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.