title: Translocation of CaMKII to dendritic microtubules supports the plasticity of local synapses.
abstract: The processing of excitatory synaptic inputs involves compartmentalized dendritic Ca(2+) oscillations. The downstream signaling evoked by these local Ca(2+) transients and their impact on local synaptic development and remodeling are unknown. Ca(2+)/calmodulin-dependent protein kinase II (CaMKII) is an important decoder of Ca(2+) signals and mediator of synaptic plasticity. In addition to its known accumulation at spines, we observed with live imaging the dynamic recruitment of CaMKII to dendritic subdomains adjacent to activated synapses in cultured hippocampal neurons. This localized and transient enrichment of CaMKII to dendritic sites coincided spatially and temporally with dendritic Ca(2+) transients. We show that it involved an interaction with microtubular elements, required activation of the kinase, and led to localized dendritic CaMKII autophosphorylation. This process was accompanied by the adjacent remodeling of spines and synaptic AMPA receptor insertion. Replacement of endogenous CaMKII with a mutant that cannot translocate within dendrites lessened this activity-dependent synaptic plasticity. Thus, CaMKII could decode compartmental dendritic Ca(2+) transients to support remodeling of local synapses.
authors.affiliation: Institut universitaire en santé mentale de Québec, Québec G1J 2G3, Canada.
authors.forename: Mado
authors.initials: M
authors.lastname: Lemieux
authors.forename: Simon
authors.initials: S
authors.lastname: Labrecque
authors.forename: Christian
authors.initials: C
authors.lastname: Tardif
authors.forename: Étienne
authors.initials: É
authors.lastname: Labrie-Dion
authors.forename: Éric
authors.initials: É
authors.lastname: Lebel
authors.forename: Paul
authors.initials: P
authors.lastname: De Koninck
mesh_terms: D000818:Animals; D002118:Calcium / Q000378:metabolism; D054732:Calcium-Calmodulin-Dependent Protein Kinase Type 2 / Q000378:metabolism*; D002478:Cells, Cultured; D003712:Dendrites / Q000378:metabolism*; D018698:Glutamic Acid / Q000378:metabolism; D005998:Glycine / Q000378:metabolism; D006624:Hippocampus / Q000166:cytology / Q000378:metabolism; D008870:Microtubules / Q000378:metabolism*; D009473:Neuronal Plasticity / Q000502:physiology*; D009474:Neurons / Q000166:cytology / Q000378:metabolism; D010766:Phosphorylation; D021381:Protein Transport; D051381:Rats; D018091:Receptors, AMPA / Q000378:metabolism; D013131:Spine / Q000166:cytology / Q000378:metabolism; D013569:Synapses / Q000378:metabolism*; D018350:alpha-Amino-3-hydroxy-5-methyl-4-isoxazolepropionic Acid / Q000378:metabolism
chemical_list: D002118:Calcium; D054732:Calcium-Calmodulin-Dependent Protein Kinase Type 2; D018698:Glutamic Acid; D005998:Glycine; D018091:Receptors, AMPA; D018350:alpha-Amino-3-hydroxy-5-methyl-4-isoxazolepropionic Acid