Neuron
Volume 57, Issue 5, 13 March 2008, Pages 719-729
Journal home page for Neuron

Article
The Subspine Organization of Actin Fibers Regulates the Structure and Plasticity of Dendritic Spines

https://doi.org/10.1016/j.neuron.2008.01.013Get rights and content
Under an Elsevier user license
open archive

Summary

Synapse function and plasticity depend on the physical structure of dendritic spines as determined by the actin cytoskeleton. We have investigated the organization of filamentous (F-) actin within individual spines on CA1 pyramidal neurons in rat hippocampal slices. Using two-photon photoactivation of green fluorescent protein fused to β-actin, we found that a dynamic pool of F-actin at the tip of the spine quickly treadmilled to generate an expansive force. The size of a stable F-actin pool at the base of the spine depended on spine volume. Repeated two-photon uncaging of glutamate formed a third pool of F-actin and enlarged the spine. The spine often released this “enlargement pool” into the dendritic shaft, but the pool had to be physically confined by a spine neck for the enlargement to be long-lasting. Ca2+/calmodulin-dependent protein kinase II regulated this confinement. Thus, spines have an elaborate mechanical nature that is regulated by actin fibers.

CELLBIO
MOLNEURO

Cited by (0)