title: Converging circuits mediate temperature and shock aversive olfactory conditioning in Drosophila.
abstract: BACKGROUND
  Drosophila learn to avoid odors that are paired with aversive stimuli. Electric shock is a potent aversive stimulus that acts via dopamine neurons to elicit avoidance of the associated odor. While dopamine signaling has been demonstrated to mediate olfactory electric shock conditioning, it remains unclear how this pathway is involved in other types of behavioral reinforcement, such as in learned avoidance of odors paired with increased temperature.
  
  
  RESULTS
  To better understand the neural mechanisms of distinct aversive reinforcement signals, we here established an olfactory temperature conditioning assay comparable to olfactory electric shock conditioning. We show that the AC neurons, which are internal thermal receptors expressing dTrpA1, are selectively required for odor-temperature but not for odor-shock memory. Furthermore, these separate sensory pathways for increased temperature and shock converge onto overlapping populations of dopamine neurons that signal aversive reinforcement. Temperature conditioning appears to require a subset of the dopamine neurons required for electric shock conditioning.
  
  
  CONCLUSIONS
  We conclude that dopamine neurons integrate different noxious signals into a general aversive reinforcement pathway.
authors.affiliation: Max-Planck-Institut für Neurobiologie, Am Klopferspitz 18, 82152 Martinsried, Germany.
authors.forename: Dana Shani
authors.initials: DS
authors.lastname: Galili
authors.affiliation: Department of Biology-Neurobiology, University of Konstanz, 78457 Konstanz, Germany.
authors.forename: Kristina V
authors.initials: KV
authors.lastname: Dylla
authors.affiliation: Department of Biology-Neurobiology, University of Konstanz, 78457 Konstanz, Germany.
authors.forename: Alja
authors.initials: A
authors.lastname: Lüdke
authors.affiliation: Max-Planck-Institut für Neurobiologie, Am Klopferspitz 18, 82152 Martinsried, Germany.
authors.forename: Anja B
authors.initials: AB
authors.lastname: Friedrich
authors.affiliation: Graduate School of Life Sciences, Tohoku University, Katahira 2-1-1, 980-8577 Sendai, Japan.
authors.forename: Nobuhiro
authors.initials: N
authors.lastname: Yamagata
authors.affiliation: Max-Planck-Institut für Neurobiologie, Am Klopferspitz 18, 82152 Martinsried, Germany.
authors.forename: Jin Yan Hilary
authors.initials: JY
authors.lastname: Wong
authors.affiliation: Max-Planck-Institut für Neurobiologie, Am Klopferspitz 18, 82152 Martinsried, Germany.
authors.forename: Chien Hsien
authors.initials: CH
authors.lastname: Ho
authors.affiliation: Department of Biology-Neurobiology, University of Konstanz, 78457 Konstanz, Germany.
authors.forename: Paul
authors.initials: P
authors.lastname: Szyszka
authors.affiliation: Max-Planck-Institut für Neurobiologie, Am Klopferspitz 18, 82152 Martinsried, Germany; Graduate School of Life Sciences, Tohoku University, Katahira 2-1-1, 980-8577 Sendai, Japan. Electronic address: hiromut@m.tohoku.ac.jp.
authors.forename: Hiromu
authors.initials: H
authors.lastname: Tanimoto
mesh_terms: D000818:Animals; D001362:Avoidance Learning; D003214:Conditioning, Classical; D059290:Dopaminergic Neurons / Q000502:physiology; D029721:Drosophila Proteins / Q000378:metabolism; D004331:Drosophila melanogaster / Q000502:physiology*; D004558:Electric Stimulation; D005260:Female; D007473:Ion Channels; D055696:Olfactory Perception; D012054:Reinforcement, Psychology; D015398:Signal Transduction; D000074025:TRPA1 Cation Channel; D050052:TRPC Cation Channels / Q000378:metabolism; D013696:Temperature
chemical_list: D029721:Drosophila Proteins; D007473:Ion Channels; D000074025:TRPA1 Cation Channel; D050052:TRPC Cation Channels; C475684:TrpA1 protein, Drosophila