The role of CaMKII as an F-actin-bundling protein crucial for maintenance of dendritic spine structure. Proc Natl Acad Sci U S A 2007 Apr 10;104(15):6418-23
Date
04/04/2007Pubmed ID
17404223Pubmed Central ID
PMC1851051DOI
10.1073/pnas.0701656104Scopus ID
2-s2.0-34547523623 (requires institutional sign-in at Scopus site) 244 CitationsAbstract
Ca(2+)-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 beta 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.
Author List
Okamoto K, Narayanan R, Lee SH, Murata K, Hayashi YAuthor
Sang H. Lee PhD Professor in the Pharmacology and Toxicology department at Medical College of WisconsinMESH terms used to index this publication - Major topics in bold
ActinsAnimals
Calcium-Calmodulin-Dependent Protein Kinase Type 2
Calcium-Calmodulin-Dependent Protein Kinases
Dendritic Spines
Hippocampus
Microscopy, Electron, Scanning
Models, Biological
Neuronal Plasticity
RNA Interference
Rats
Signal Transduction
Synapses
