Olfactory conditioning of proboscis activity in Drosophila melanogaster.
Olfactory learning and memory processes in Drosophila have been well investigated with aversive conditioning, but appetitive conditioning has rarely been documented. Here, we report for the first time individual olfactory conditioning of proboscis activity in restrained Drosophila melanogaster. The protocol was adapted from those developed for proboscis extension conditioning in the honeybee Apis mellifera. After establishing a scale of small proboscis movements necessary to characterize responses to olfactory stimulation, we applied Pavlovian conditioning, with five trials consisting of paired presentation of a banana odour and a sucrose reward. Drosophila showed conditioned proboscis activity to the odour, with a twofold increase of percentage of responses after the first trial. No change occurred in flies experiencing unpaired presentations of the stimuli, confirming an associative basis for this form of olfactory learning. The adenylyl cyclase mutant rutabaga did not exhibit learning in this paradigm. This protocol generated at least a short-term memory of 15 min, but no significant associative memory was detected at 1 h. We also showed that learning performance was dependent on food motivation, by comparing flies subjected to different starvation regimes.
Chabaud
Marie-Ange
MA
Développement, Evolution et Plasticité du Système Nerveux, CNRS, Bât. 32/33, Avenue de la Terrasse, 91198, Gif-sur-Yvette cedex, France.
Devaud
Jean-Marc
JM
Pham-Delègue
Minh-Hà
MH
Preat
Thomas
T
Kaiser
Laure
L
D000262:Adenylyl Cyclases / Q000235:genetics; D000818:Animals; D030801:Animals, Genetically Modified; D001070:Appetitive Behavior / Q000502:physiology*; D001245:Association Learning / Q000502:physiology; D001522:Behavior, Animal; D003214:Conditioning, Classical / Q000502:physiology*; D029721:Drosophila Proteins / Q000235:genetics; D004331:Drosophila melanogaster / Q000502:physiology*; D005260:Female; D009068:Movement / Q000502:physiology; D009833:Olfactory Pathways / Q000502:physiology*; D012679:Sense Organs / Q000502:physiology*; D012903:Smell / Q000502:physiology*; D013217:Starvation / Q000503:physiopathology
D029721:Drosophila Proteins; D000262:Adenylyl Cyclases; C479926:Rut protein, Drosophila