Date of Thesis

Spring 2020


The insect odorant receptor, OR, gene family has been hypothesized to play a critical role in reproduction. Odorant receptor proteins, located on the olfactory sensory neuronal dendrites, detect odorant chemicals such as pheromones and then mediate key behaviors such as mate choice. Although olfaction is known to play a predominant role in sexual communication, there are still large numbers of olfactory genes that have not been studied in many insect species including fireflies. In this study, I investigated the sequencing data of one of the common eastern fireflies, Photinus pyralis (Coleoptera: Lampyridae). This firefly species is well known for their use of light signals to attract mates, but our knowledge of their odorant receptors is still incomplete. Recent advances in genome sequencing have provided tools to identify the OR gene repertoires in P. pyralis sequencing data. The aim of this study was to develop an OR gene repertoire of P. pyralis, which might shed light on our knowledge about their ability to detect chemical signals at the molecular level. Using computational analysis, I identified a set of 27 putative OR genes including one odorant receptor co-receptor (ORco) gene in the P. pyralis genome and antennal transcriptome. A phylogenetic tree was constructed from OR sequences of P. pyralis and other beetle species to show the relationship of ORs among beetles. Results of this study will provide a basis foundation for future studies on the expression and function of the P. pyralis OR candidates.


odorant receptor, fireflies, chemoreception, mating communication

Access Type

Honors Thesis

Degree Type

Bachelor of Science



First Advisor

Sarah Lower

Second Advisor

Ken Field