title: The GABAergic anterior paired lateral neurons facilitate olfactory reversal learning in Drosophila.
abstract: Reversal learning has been widely used to probe the implementation of cognitive flexibility in the brain. Previous studies in monkeys identified an essential role of the orbitofrontal cortex (OFC) in reversal learning. However, the underlying circuits and molecular mechanisms are poorly understood. Here, we use the T-maze to investigate the neural mechanism of olfactory reversal learning in Drosophila. By adding a reversal training cycle to the classical learning protocol, we show that wild-type flies are able to reverse their choice according to the alteration of conditioned stimulus (CS)-unconditioned stimulus (US) contingency. The reversal protocol induced a specific suppression of the initial memory, an effect distinct from memory decay or extinction. GABA down-regulation in the anterior paired lateral (APL) neurons, which innervate the mushroom bodies (MBs), eliminates this suppression effect and impairs normal reversal. These findings reveal that inhibitory regulation from the GABAergic APL neurons facilitates olfactory reversal learning by suppressing initial memory in Drosophila.
authors.affiliation: Institute of Neuroscience, State Key Laboratory of Neuroscience, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200031, China.
authors.forename: Yanying
authors.initials: Y
authors.lastname: Wu
authors.forename: Qingzhong
authors.initials: Q
authors.lastname: Ren
authors.forename: Hao
authors.initials: H
authors.lastname: Li
authors.forename: Aike
authors.initials: A
authors.lastname: Guo
mesh_terms: D000818:Animals; D030801:Animals, Genetically Modified; D003214:Conditioning, Classical / Q000502:physiology*; D015536:Down-Regulation / Q000235:genetics; D004330:Drosophila; D029721:Drosophila Proteins / Q000235:genetics / Q000378:metabolism; D034281:Dynamins / Q000235:genetics / Q000378:metabolism; D005108:Extinction, Psychological / Q000502:physiology; D059330:GABAergic Neurons / Q000502:physiology*; D005968:Glutamate Decarboxylase / Q000235:genetics / Q000378:metabolism; D053403:Lateral Line System / Q000166:cytology* / Q000502:physiology; D008568:Memory / Q000502:physiology*; D024521:Mushroom Bodies / Q000166:cytology / Q000502:physiology; D009154:Mutation / Q000235:genetics; D009433:Neural Inhibition / Q000235:genetics / Q000502:physiology; D009812:Odorants; D034622:RNA Interference / Q000502:physiology; D012193:Reversal Learning / Q000502:physiology*; D012903:Smell / Q000235:genetics / Q000502:physiology*; D014157:Transcription Factors / Q000235:genetics; D005680:gamma-Aminobutyric Acid / Q000378:metabolism
chemical_list: D029721:Drosophila Proteins; C557617:GAL4 protein, Drosophila; D014157:Transcription Factors; D005680:gamma-Aminobutyric Acid; D034281:Dynamins; C439628:shi protein, Drosophila; D005968:Glutamate Decarboxylase