title: Functional feedback from mushroom bodies to antennal lobes in the Drosophila olfactory pathway.
abstract: Feedback plays important roles in sensory processing. Mushroom bodies are believed to be involved in olfactory learning/memory and multisensory integration in insects. Previous cobalt-labeling studies have suggested the existence of feedback from the mushroom bodies to the antennal lobes in the honey bee. In this study, the existence of functional feedback from Drosophila mushroom bodies to the antennal lobes was investigated through ectopic expression of the ATP receptor P2X(2) in the Kenyon cells of mushroom bodies. Activation of Kenyon cells induced depolarization in projection neurons and local interneurons in the antennal lobes in a nicotinic receptor-dependent manner. Activation of Kenyon cell axons in the betagamma-lobes in the mushroom body induced more potent responses in the antennal lobe neurons than activation of Kenyon cell somata. Our results indicate that functional feedback from Kenyon cells to projection neurons and local interneurons is present in Drosophila and is likely mediated by the betagamma-lobes. The presence of this functional feedback from the mushroom bodies to the antennal lobes suggests top-down modulation of olfactory information processing in Drosophila.
authors.affiliation: Institute of Neuroscience, State Key Laboratory of Neuroscience, Shanghai Institutes for Biological Sciences, and Graduate School of Chinese Academy of Sciences, Chinese Academy of Sciences, Shanghai 200031, China.
authors.forename: Aiqun
authors.initials: A
authors.lastname: Hu
authors.forename: Wei
authors.initials: W
authors.lastname: Zhang
authors.forename: Zuoren
authors.initials: Z
authors.lastname: Wang
mesh_terms: D000109:Acetylcholine / Q000502:physiology; D000255:Adenosine Triphosphate / Q000494:pharmacology; D000818:Animals; D030801:Animals, Genetically Modified; D004330:Drosophila / Q000187:drug effects / Q000235:genetics / Q000502:physiology*; D055724:Electrophysiological Phenomena; D056228:Feedback, Sensory; D007395:Interneurons / Q000502:physiology; D024521:Mushroom Bodies / Q000187:drug effects / Q000502:physiology*; D009833:Olfactory Pathways / Q000187:drug effects / Q000502:physiology*; D018034:Olfactory Receptor Neurons / Q000502:physiology; D018408:Patch-Clamp Techniques; D018048:Receptors, Purinergic P2 / Q000235:genetics / Q000378:metabolism; D058476:Receptors, Purinergic P2X2; D011994:Recombinant Proteins / Q000235:genetics / Q000378:metabolism; D011984:Sensory Receptor Cells / Q000502:physiology; D009435:Synaptic Transmission
chemical_list: D018048:Receptors, Purinergic P2; D058476:Receptors, Purinergic P2X2; D011994:Recombinant Proteins; D000255:Adenosine Triphosphate; D000109:Acetylcholine