Odorant Binding Protein C17 Contributes to the Response to Oil in .

The red flour beetle, (), generates great financial losses to the grain storage and food processing industries. Previous studies have shown that essential oil (EO) from () has strong contact toxicity to larvae of the beetle, and odorant-binding proteins (OBPs) contribute to the defense of larvae against . However, the functions of OBPs in insects defending against plant oil is still not clear. Here, expression of one gene, , was significantly induced 12-72 h after EO exposure. Furthermore, compared to the control group, RNA interference (RNAi) against resulted in a higher mortality rate after EO treatment, which suggests that involves in the defense against EO and induces a declining sensitivity to EO. In addition, the tissue expression profile analysis revealed that the expression of was more abundant in the metabolic detoxification organs of the head, fat body, epidermis, and hemolymph than in other larval tissue. The expression profile of developmental stages showed that had a higher level in early and late adult stages than in other developmental stages. Taken together, these results suggest that could participate in the sequestration process of exogenous toxicants in larvae.