SPLTRAK Abstract Submission
Olfaction, a Sex Attractant, and Tsetse Flies
John R. Carlson1, Shimaa A.M. Ebrahim1, Hany K.M. Dweck1, Sebastian Chahda1, Neeraj Soni1, Brian Weiss2
1Dept. of Molecular, Cellular and Developmental Biology, Yale University, New Haven, CT, United States
2Dept. of Epidemiology of Microbial Disease, Yale School of Public Health, New Haven, CT, United States

The work of Gordon Shepherd has inspired generations of researchers studying olfaction in a wide range of organisms.  Chemical communication in insects is elegant in concept and sophisticated in design. Pheromones are used by many insects to recognize a conspecific in a habitat that may contain thousands of insect species. However, little is known about chemical communication in tsetse flies.  Tsetse spreads disease across much of sub-Saharan Africa. They can carry African trypanosomes, which they transmit when they bite humans or animals. In humans the parasites cause African Sleeping Sickness, and in livestock they cause a disease called nagana, which has a devastating effect on the economic development of Africa.                                                                                                                                                      The antenna of the tsetse fly Glossina morsitans contains four classes of olfactory sensilla. Sensilla in one region of the antenna were found via electrophysiology to respond to a variety of odorants, via both excitatory and inhibitory responses. Certain odor receptors of tsetse respond to host odors in an in vivo expression system.  Screening of odorants that activate one receptor has identified 2-propanol as a candidate for an environmentally friendly and practical tsetse attractant. We recently found that G. morsitans produces compounds that elicit strong behavioral responses from males. Methyl palmitoleate (MPO), methyl palmitate (MP), and methyl oleate (MO) elicit male behavioral responses in two paradigms.  Perfuming a virgin female of another Glossina species with MPO elicits mounting behavior from a G. morsitans male. All three compounds elicit electrophysiological responses from ORNs of G. morsitans. In addition, we found that infection with trypanosomes modulated the chemical profile in mated flies, and that infected females had reduced receptivity to mating.