role of CaMKII as an F-actin-bundling protein crucial for maintenance of dendritic spine structure

Ca²⁺-calmodulin-dependent protein kinase II (CaMKII) is a serine/threonine protein kinase critically involved in synaptic plasticity in the brain. It is highly concentrated in the postsynaptic density fraction, exceeding the amount of any other signal transduction molecules. Because kinase signaling...

Full description

Saved in:
Bibliographic Details
Published in:Proceedings of the National Academy of Sciences - PNAS 2007-04, Vol.104 (15), p.6418-6423
Main Authors: Okamoto, Ken-Ichi, Narayanan, Radhakrishnan, Lee, Sang H, Murata, Kazuyoshi, Hayashi, Yasunori
Format: Article
Language:English
Subjects:
Actins
Actins - metabolism
Animals
Biochemistry
Biological Sciences
Brain
Bundling
Calcium-Calmodulin-Dependent Protein Kinase Type 2
Calcium-Calmodulin-Dependent Protein Kinases - genetics
Calcium-Calmodulin-Dependent Protein Kinases - metabolism
Complementary DNA
Cytoskeleton
Dendritic spines
Dendritic Spines - metabolism
Dendritic Spines - ultrastructure
Depolymerization
Hippocampus - metabolism
Kinases
Microscopy, Electron, Scanning
Models, Biological
Molecules
Neuronal Plasticity - physiology
Neurons
Neurosciences
Polymerization
Rats
RNA Interference
Signal transduction
Signal Transduction - physiology
Synapses
Synapses - metabolism
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Ca²⁺-calmodulin-dependent protein kinase II (CaMKII) is a serine/threonine protein kinase critically involved in synaptic plasticity in the brain. It is highly concentrated in the postsynaptic density fraction, exceeding the amount of any other signal transduction molecules. Because kinase signaling can be amplified by catalytic reaction, why CaMKII exists in such a large quantity has been a mystery. Here, we provide biochemical evidence that CaMKII is capable of bundling F-actin through a stoichiometric interaction. Consistent with this evidence, in hippocampal neurons, RNAi-mediated down-regulation of CaMKII leads to a reduction in the volume of dendritic spine head that is mediated by F-actin dynamics. An overexpression of CaMKII slowed down the actin turnover in the spine head. This activity was associated with β subunit of CaMKII in a manner requiring its actin-binding and association domains but not the kinase domain. This finding indicates that CaMKII serves as a central signaling molecule in both functional and structural changes during synaptic plasticity.
ISSN:0027-8424
1091-6490
DOI:10.1073/pnas.0701656104