Date of Award

Spring 2011

Document Type

Restricted Thesis

Terms of Use

© 2011 Zheng Zheng. All rights reserved. Access to this work is restricted to users within the Swarthmore College network and may only be used for non-commercial, educational, and research purposes. Sharing with users outside of the Swarthmore College network is expressly prohibited. For all other uses, including reproduction and distribution, please contact the copyright holder.

Degree Name

Bachelor of Arts


Biology Department

First Advisor

Kathleen King Siwicki


Drosophila melanogaster males are capable of learning from an unsuccessful courtship experience with a mated female, and subsequently exhibit generalized courtship suppression toward virgin females. Learned courtship suppression has been classified as a form of associative learning, and is also called associative courtship conditioning (Siwicki et al. 2005). A novel gene, pickpocket25, which encodes a protein subunit of a Degenerin/epithelial Na⁺ channel, is specifically expressed in male appendages and chemosensory neurons indispensable for the male's detection of female pheromones (Lin et al, 2005). We investigated whether blocking neurotransmission from ppk25-expressing chemosensory neuron would disrupt the acquisition or the expression of short-term memory in male flies. Neurotransmitter release from the ppk25-expressing neurons was blocked using the Gal-4 driven UAS-shibireᵗˢ¹ transgene. Consistent with the ppk25-expressing neurons' putative role in the chemosensory detection of female pheromones, blocking neurotransmission from these cells resulted in significant reduction in courtship index (CI) of socially naive ppk25-shibireᵗˢ¹ males. Despite experimental manipulations of these neurons during training and/or testing phases of the experiment, the ppk25-shibireᵗˢ¹ males expressed normal 5' and 20' memory. These results suggest that neither the acquisition nor the expression of 5' and 20' memory of courtship conditioning requires the activity of these chemosensory neurons. Since courtship behavior involves multimodal sensory cues, other types of sensory information may be sufficient to produce this form of associative learning and memory in Drosophila melanogaster males.