Establishment and characterization of a reliable long-term memory courtship conditioning paradigm in Drosophila melanogaster

After experience courting an unreceptive mated female fly, a subject male will reduce his subsequent courtship of a virgin female compared to naives. This effect termed courtship conditioning, is most well documented in short-term memory. Previous studies have also used mated female training to induce long-term courtship suppression towards virgin female targets (McBride et al., 1999), but attempts to reproduce these results have been varied (Nigrini, 1999; Sakai et al., 20(4). In order to find a more reliable way to induce long-term memory, we used a spaced training experience with two types of pheromonally feminized males, Tp2602-tra and Tai2, to produce memory at 1 day toward Tp2602-tra males. Massed training with Tp2602-tra males was not sufficient to induce long-term memory toward virgin females. These pheromonally-manipulated male flies, along with hydrocarbon-depleted hs-tra females and Canton-S virgin females, were also used as test targets to evaluate the role of pheromones in eliciting short- and long-term memory. We also characterized the effects of short- and long-term memory training on different aspects of the subsequent behavioral response in an attempt to discern to what degree each sensory modality affects courtship conditioning. Latency to initiate courtship was the parameter most affected by training in both short- and long-term memory, thus indicating that gustatory cues arc the most salient aspect of the training experience