High Antennal Expression of and Participate in the Recognition of Alarm Pheromones by Buren.

Insects have highly developed olfactory systems in which cytochrome P450s (CYPs) were involved as odor-degrading enzymes throughout the olfactory recognition of odor compounds by insects to avoid continuous stimulation of signaling molecules and thus damage to the olfactory nervous. To understand whether the highly expressed CYPs in the antennae play an olfactory function in worker, in this study, we find six highly expressed antennal CYPs from the transcriptome of . Multiple sequence alignment and phylogenetic analysis divided them into two families: the CYP3 family (, ) and the CYP4 family (, , , ). The expression patterns of these six CYPs were analyzed by RT-qPCR, which revealed that and were only highly expressed in the antennae of adult workers. The expression of and in workers was markedly diminished after feeding with dsRNA. The electroantennography (EAG) assay demonstrated that the silencing of either or resulted in a notable reduction in the EAG response of workers to 2-ethyl-3,6(5)-dimethylpyrazine (EDMP). Furthermore, the trajectory behavior assay showed that the worker's range and speed of movement in response to EDMP significant decreased after the silencing of and . The findings indicated that both and were implicated in the recognition of EDMP by .