Work

The Spread of Ras Activity Triggered by Activation of a Single Dendritic Spine

Year: 2008

Type: article

Abstract: In neurons, individual dendritic spines isolate N-methyl-d-aspartate (NMDA) receptor-mediated calcium ion (Ca2+) accumulations from the dendrite and other spines. However, the extent to which spines compartmentalize signaling events downstream of Ca2+ influx is not known. We combined two-photon fluorescence lifetime imaging with two-photon glutamate uncaging to image the activity of the small guanosine triphosphatase Ras after NMDA receptor activation at individual spines. Induction of long-term potentiation (LTP) triggered robust Ca2+-dependent Ras activation in single spines that decayed in approximately 5 minutes. Ras activity spread over approximately 10 micrometers of dendrite and invaded neighboring spines by diffusion. The spread of Ras-dependent signaling was necessary for the local regulation of the threshold for LTP induction. Thus, Ca2+-dependent synaptic signals can spread to couple multiple synapses on short stretches of dendrite.

Source: Science

DOI: 10.1126/science.1159675

Authors: Christopher D. Harvey, Ryohei Yasuda, Haining Zhong, Karel Svoboda

Institutions: Howard Hughes Medical Institute, Janelia Research Campus, Cold Spring Harbor Laboratory, Duke Medical Center

Language: English

Topic: Neuroscience and Neuropharmacology Research

Subfield: Cellular and Molecular Neuroscience

Field: Neuroscience

Domain: Life Sciences

Open Access status: green

Funders: Howard Hughes Medical Institute, Autism Speaks, National Institute of Mental Health

Awards: G2215152856, Mechanisms of Ras signaling in single synapses