Speaker
Description
The success of social insect colonies lies in the capacity of all members of the society to behave in a well-organized and context-dependent manner, thanks to elaborate communication among colony members. Honey bees, in particular, use a sophisticated chemical communication system based on the use of a high number of pheromones, most of which have already been identified. How does the social insect brain manage to encode such a plethora of highly‐meaningful and ecologically‐relevant signals? Despite substantial knowledge acquired on olfactory processing in this species, the mechanism of pheromonal coding remains poorly understood. In particular, olfactory receptors (ORs) detecting social pheromones are still unknown. We thus used heterologous expression in the Drosophila “empty neuron system”, coupled with transcuticular calcium imaging and electrophysiology. We deorphanized two odorant receptors, AmelOR136 and AmelOR109, which detect constituents of the alarm pheromone. AmelOR136 exhibits a sparse coding strategy, suggesting a finely tuned mechanism for efficient communication in alarm situations. In contrast, AmelOR109 is a more broadly-tuned receptor, responding to diverse odorants, including pheromones. This study paves the way for understanding pheromonal coding in the honey bee brain.
