Biological Sciences Seminar - Karen Kiemnec-Tyburczy, PhD, Humboldt State University will present “The molecular basis of pheromone communication in lungless salamanders”.
I employ a combination of behavioral, molecular and genetic approaches to examine the evolution of the chemical signaling system involved in the ritualized courtships of plethodontid (lungless) salamanders. Many species in this family use sex pheromone communication during courtship whereby males deliver a “cocktail” of proteins to females to increase receptivity to mating. This unique system provides a tractable model for studying the evolution of chemical communication across multiple scales, from genes to development to behavior. Most plethodontid pheromones are encoded by multi-gene families, are highly variable, and have experienced diversifying selection. In addition, pheromone composition can vary drastically across species. Using a functional genomics approach, I discovered highly expressed but previously uncharacterized gland proteins whose function warrant further study; these may also play a role in communication during courtship. I am also investigating the molecular basis of pheromone detection in these salamanders. I isolated pheromone receptor genes from one focal species (Plethodon shermani) and used in situ hybridization to map the expression of gene families to distinct regions of nasal cavity epithelia. I found that some receptor classes exhibit sexually dimorphic expression, consistent with sex-specific responses to pheromones. Plethodontid salamanders provide valuable insight into how evolutionary processes can shape the signals and receptors in chemical signaling systems.
When: Friday, February 8, 2019
Time: 4:00 PM
Location: Science B 133