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CAMP Signals in Drosophila Motor Neurons Are Confined to Single Synaptic Boutons.

ABSTRACT: The second messenger cyclic AMP (cAMP) plays an important role in synaptic plasticity. Although there is evidence for local control of synaptic transmission and plasticity, it is less clear whether a similar spatial confinement of cAMP signaling exists. Here, we suggest a possible biophysical basis for the site-specific regulation of synaptic plasticity by cAMP, a highly diffusible small molecule that transforms the physiology of synapses in a local and specific manner. By exploiting the octopaminergic system of Drosophila, which mediates structural synaptic plasticity via a cAMP-dependent pathway, we demonstrate the existence of local cAMP signaling compartments of micrometer dimensions within single motor neurons. In addition, we provide evidence that heterogeneous octopamine receptor localization, coupled with local differences in phosphodiesterase activity, underlies the observed differences in cAMP signaling in the axon, cell body, and boutons.

SUBMITTER: Maiellaro I

PROVIDER: S-EPMC5098120 | biostudies-literature | 2016 Oct

REPOSITORIES: biostudies-literature

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cAMP Signals in Drosophila Motor Neurons Are Confined to Single Synaptic Boutons.

Maiellaro Isabella I Lohse Martin J MJ Kittel Robert J RJ Calebiro Davide D

Cell reports 20161001 5

The second messenger cyclic AMP (cAMP) plays an important role in synaptic plasticity. Although there is evidence for local control of synaptic transmission and plasticity, it is less clear whether a similar spatial confinement of cAMP signaling exists. Here, we suggest a possible biophysical basis for the site-specific regulation of synaptic plasticity by cAMP, a highly diffusible small molecule that transforms the physiology of synapses in a local and specific manner. By exploiting the octopam ...[more]

PMID: 27783939

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