title: Delayed dopamine signaling of energy level builds appetitive long-term memory in Drosophila.
abstract: Sensory cues relevant to a food source, such as odors, can be associated with post-ingestion signals related either to food energetic value or toxicity. Despite numerous behavioral studies, a global understanding of the mechanisms underlying these long delay associations remains out of reach. Here, we demonstrate in Drosophila that the long-term association between an odor and a nutritious sugar depends on delayed post-ingestion signaling of energy level. We show at the neural circuit level that the activity of two pairs of dopaminergic neurons is necessary and sufficient to signal energy level to the olfactory memory center. Accordingly, we have identified in these dopaminergic neurons a delayed calcium trace that correlates with appetitive long-term memory formation. Altogether, these findings demonstrate that the Drosophila brain remembers food quality through a two-step mechanism that consists of the integration of olfactory and gustatory sensory information and then post-ingestion energetic value.
authors.affiliation: Genes and Dynamics of Memory Systems, Brain Plasticity Unit, CNRS, ESPCI-ParisTech, PSL Research University, 75005 Paris, France.
authors.forename: Pierre-Yves
authors.initials: PY
authors.lastname: Musso
authors.affiliation: Genes and Dynamics of Memory Systems, Brain Plasticity Unit, CNRS, ESPCI-ParisTech, PSL Research University, 75005 Paris, France; Laboratoire Aimé Cotton, CNRS, Université Paris-Sud, ENS-Cachan, 91400 Orsay, France. Electronic address: paul.tchenio@espci.fr.
authors.forename: Paul
authors.initials: P
authors.lastname: Tchenio
authors.affiliation: Genes and Dynamics of Memory Systems, Brain Plasticity Unit, CNRS, ESPCI-ParisTech, PSL Research University, 75005 Paris, France. Electronic address: thomas.preat@espci.fr.
authors.forename: Thomas
authors.initials: T
authors.lastname: Preat
mesh_terms: D000818:Animals; D001921:Brain / Q000502:physiology; D004298:Dopamine / Q000378:metabolism*; D059290:Dopaminergic Neurons / Q000378:metabolism; D004330:Drosophila / Q000378:metabolism*; D029721:Drosophila Proteins / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism; D004734:Energy Metabolism; D005947:Glucose / Q000494:pharmacology; D057567:Memory, Long-Term / Q000187:drug effects / Q000502:physiology*; D034622:RNA Interference; D015398:Signal Transduction / Q000187:drug effects; D013549:Sweetening Agents / Q000494:pharmacology; D014157:Transcription Factors / Q000378:metabolism
chemical_list: D029721:Drosophila Proteins; C557617:GAL4 protein, Drosophila; D013549:Sweetening Agents; D014157:Transcription Factors; D005947:Glucose; D004298:Dopamine