Multi-level analysis of honey bee queen post-mating changes and queen-worker interactions

Mating is an intricate process that causes many changes on behavioral, physiological, and molecular level in females of sexually-reproducing species. Previous studies on honey bees suggest that insemination volume and seminal fluid components both play a role in triggering queen post-mating changes. However, the long-term effects of these factors had not been previously characterized. By manipulating the mating process we examined the factors causing immediate behavioral changes and longer-term physiological and molecular changes in queens that reached their final reproductive state of high ovary activation. Our data indicate that carbon dioxide (used as an anesthetic during instrumental insemination), physical manipulation of the genital tract, and insemination volume cause early behavioral changes, while seminal fluid components play a role in maintaining long-term physiological and transcriptional changes. Mating also causes changes in production of queen pheromones which are important for regulating the behavior and physiology of workers, as well as overall colony organization.  We found that the above mentioned factors have distinct effects on two different pheromone producing glands in queens, and workers can detect these differences. Furthermore, we demonstrated that the queen insemination volume affected worker behavior and physiology in colonies, as well as queen overwintering survival. In conjunction with previous studies, our results show that multiple factors are involved in regulating short- and long-term post-mating changes in honey bee queens and can alter social interactions in the entire colony. These results will provide fundamental insights into insect reproduction, as well as lead to improved breeding techniques of honey bees and other agriculturally important insects.