Date of Award


Degree Type


Degree Name

Master of Science (MS)




Yasir Ahmed-Braimah


Computational Genomics;Drosophila;Gene expression;Microbiome;NGS;Postmating responses

Subject Categories

Biology | Life Sciences


Mating induces crucial changes in Drosophila females, influencing vital aspects of behavior and physiology essential for reproductive success. These changes primarily result from gene expression shifts in the female reproductive tract. DNA sequencing and bioinformatics advances have deepened our understanding of postmating responses in Drosophila at the transcriptional level. However, the majority of these studies are confined to D. melanogaster, lack tissue-specific investigations, and are extensively focused on the composition of the ejaculate and the role of male reproductive proteins transferred during mating. This study delves into the dynamic lower reproductive tract of D. virilis subgroup species, exploring the postmating responses at both transcriptional and microbial levels, utilizing dense time-course mRNA abundance profiling and targeted (16S rRNA) sequencing approaches. The dense mRNA profiling approach allowed us to identify many more differentially expressed genes (∼1000 differentially expressed genes) than classic transcriptomic approaches, only considering the sparse time points and enabled us to determine the changes in transcript abundance with high confidence. Since there is no information present on the composition and diversity of the reproductive tract microbiome in Drosophila, I first characterized the reproductive microbiota in four D. virilis subgroup species before investigating postmating microbial shifts. The lower reproductive tract showcased a dominance of Proteobacteria and Firmicutes, consistent with findings in humans and other insects. Investigating postmating microbial changes revealed significant alterations in the lower reproductive tract microbiota, particularly in the abundance of Proteobacteria and Firmicutes in both mated males and females. The work within this thesis contributes to a comprehensive understanding of the intricate dynamics of postmating responses, gene interactions, and microbiota in the lower reproductive system of Drosophila, with implications for reproductive success and immune responses.


Open Access

Available for download on Friday, January 17, 2025

Included in

Biology Commons