title: Dopaminergic modulation of cAMP drives nonlinear plasticity across the Drosophila mushroom body lobes.
abstract: BACKGROUND
  Activity of dopaminergic neurons is necessary and sufficient to evoke learning-related plasticity in neuronal networks that modulate learning. During olfactory classical conditioning, large subsets of dopaminergic neurons are activated, releasing dopamine across broad sets of postsynaptic neurons. It is unclear how such diffuse dopamine release generates the highly localized patterns of plasticity required for memory formation.
  
  
  RESULTS
  Here we have mapped spatial patterns of dopaminergic modulation of intracellular signaling and plasticity in Drosophila mushroom body (MB) neurons, combining presynaptic thermogenetic stimulation of dopaminergic neurons with postsynaptic functional imaging in vivo. Stimulation of dopaminergic neurons generated increases in cyclic AMP (cAMP) across multiple spatial regions in the MB. However, odor presentation paired with stimulation of dopaminergic neurons evoked plasticity in Ca(2+) responses in discrete spatial patterns. These patterns of plasticity correlated with behavioral requirements for each set of MB neurons in aversive and appetitive conditioning. Finally, broad elevation of cAMP differentially facilitated responses in the gamma lobe, suggesting that it is more sensitive to elevations of cAMP and that it is recruited first into dopamine-dependent memory traces.
  
  
  CONCLUSIONS
  These data suggest that the spatial pattern of learning-related plasticity is dependent on the postsynaptic neurons' sensitivity to cAMP signaling. This may represent a mechanism through which single-cycle conditioning allocates short-term memory to a specific subset of eligible neurons (gamma neurons).
authors.affiliation: Department of Neuroscience, The Scripps Research Institute, Jupiter, FL 33458, USA.
authors.forename: Tamara
authors.initials: T
authors.lastname: Boto
authors.affiliation: Department of Neuroscience, The Scripps Research Institute, Jupiter, FL 33458, USA.
authors.forename: Thierry
authors.initials: T
authors.lastname: Louis
authors.affiliation: SURF Program, The Scripps Research Institute, Jupiter, FL 33458, USA.
authors.forename: Kantiya
authors.initials: K
authors.lastname: Jindachomthong
authors.affiliation: Division of Cell Biology, The Netherlands Cancer Institute, Amsterdam, the Netherlands.
authors.forename: Kees
authors.initials: K
authors.lastname: Jalink
authors.affiliation: Department of Neuroscience, The Scripps Research Institute, Jupiter, FL 33458, USA. Electronic address: stomchik@scripps.edu.
authors.forename: Seth M
authors.initials: SM
authors.lastname: Tomchik
mesh_terms: D000818:Animals; D000242:Cyclic AMP / Q000378:metabolism*; D004298:Dopamine / Q000378:metabolism*; D059290:Dopaminergic Neurons / Q000378:metabolism*; D004330:Drosophila / Q000502:physiology*; D031541:Fluorescence Resonance Energy Transfer; D018613:Microscopy, Confocal; D008959:Models, Neurological; D024521:Mushroom Bodies / Q000378:metabolism / Q000502:physiology*; D009473:Neuronal Plasticity / Q000502:physiology*; D012903:Smell / Q000502:physiology*
chemical_list: D000242:Cyclic AMP; D004298:Dopamine