CaMKII-dependent phosphorylation of GluK5 mediates plasticity of kainate receptors.
EMBO J. 2013-01-04; 32(4): 496-510
Lire sur PubMed
1. EMBO J. 2013 Feb 20;32(4):496-510. doi: 10.1038/emboj.2012.334. Epub 2013 Jan 4.
CaMKII-dependent phosphorylation of GluK5 mediates plasticity of kainate
Carta M(1), Opazo P, Veran J, Athané A, Choquet D, Coussen F, Mulle C.
(1)Université Bordeaux, Institut Interdisciplinaire de Neurosciences, UMR 5297,
EMBO J. 2013 Feb 20;32(4):487-9.
Calmodulin-dependent kinase II (CaMKII) is key for long-term potentiation of
synaptic AMPA receptors. Whether CaMKII is involved in activity-dependent
plasticity of other ionotropic glutamate receptors is unknown. We show that
repeated pairing of pre- and postsynaptic stimulation at hippocampal mossy fibre
synapses induces long-term depression of kainate receptor (KAR)-mediated
responses, which depends on Ca(2+) influx, activation of CaMKII, and on the GluK5
subunit of KARs. CaMKII phosphorylation of three residues in the C-terminal
domain of GluK5 subunit markedly increases lateral mobility of KARs, possibly by
decreasing the binding of GluK5 to PSD-95. CaMKII activation also promotes
surface expression of KARs at extrasynaptic sites, but concomitantly decreases
its synaptic content. Using a molecular replacement strategy, we demonstrate that
the direct phosphorylation of GluK5 by CaMKII is necessary for KAR-LTD. We
propose that CaMKII-dependent phosphorylation of GluK5 is responsible for
synaptic depression by untrapping of KARs from the PSD and increased diffusion
away from synaptic sites.
PMID: 23288040 [Indexed for MEDLINE]