Professor The Ohio State University Columbus, Ohio
Insects are the most diverse multi-cellular organisms on the planet. Parasitoid wasps, in particular, have an incredible species richness and are the second most-described group of insects behind Coleoptera. Their astounding diversity has given rise to questions addressing the mechanisms by which host-associated parasitoids diversify. Over time, parasitoid wasps have undergone adaptive radiations that are seemingly correlated with shifts in host-associations, likely a result of evolving chemical receptor proteins that mediate olfaction of unexploited host groups. Therefore, we believe chemosensory speciation drives parasitoid diversification and may inform mechanisms of evolution of olfactory gene families. To address our long-term goals of mapping the olfactory processes responsible for parasitoid host-finding and acceptance, we have annotated odorant binding protein (OBP) sequences in the Trissolcus basalis genome and modeled their 3D structure. OBPs may act as the first filter in odor coding, as they are responsible for transporting ligands from the environment to the olfactory receptors expressed on the surface of sense cells. Variation in OBP and receptor specificity to ligands may contribute to a parasitoid’s ability to shift host groups.
