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Activation of CaMKII in single dendritic spines during long-term potentiation.

ABSTRACT: Calcium/calmodulin-dependent kinase II (CaMKII) plays a central part in long-term potentiation (LTP), which underlies some forms of learning and memory. Here we monitored the spatiotemporal dynamics of CaMKII activation in individual dendritic spines during LTP using two-photon fluorescence lifetime imaging microscopy, in combination with two-photon glutamate uncaging. Induction of LTP and associated spine enlargement in single spines triggered transient ( approximately 1 min) CaMKII activation restricted to the stimulated spines. CaMKII in spines was specifically activated by NMDA receptors and L-type voltage-sensitive calcium channels, presumably by nanodomain Ca(2+) near the channels, in response to glutamate uncaging and depolarization, respectively. The high degree of compartmentalization and channel specificity of CaMKII signalling allow stimuli-specific spatiotemporal patterns of CaMKII signalling and may be important for synapse-specificity of synaptic plasticity.

SUBMITTER: Lee SJ

PROVIDER: S-EPMC2719773 | biostudies-literature | 2009 Mar

REPOSITORIES: biostudies-literature

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Activation of CaMKII in single dendritic spines during long-term potentiation.

Lee Seok-Jin R SJ Escobedo-Lozoya Yasmin Y Szatmari Erzsebet M EM Yasuda Ryohei R

Nature 20090301 7236

Calcium/calmodulin-dependent kinase II (CaMKII) plays a central part in long-term potentiation (LTP), which underlies some forms of learning and memory. Here we monitored the spatiotemporal dynamics of CaMKII activation in individual dendritic spines during LTP using two-photon fluorescence lifetime imaging microscopy, in combination with two-photon glutamate uncaging. Induction of LTP and associated spine enlargement in single spines triggered transient ( approximately 1 min) CaMKII activation ...[more]

PMID: 19295602

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