BarH2 regulates odorant binding protein 6 expression to mediate 2,3‐butanediol recognition in female Callosobruchus chinensis

BACKGROUND The insect olfactory system plays an important role in guiding chemical‐driven behaviors, such as host selection, oviposition, and mating. Odorant‐binding proteins (OBPs) serve as a bridge for transmitting chemical signals in insects; however, the transcriptional regulation of their expression patterns remains unknown. RESULTS In this study, we demonstrated that CchiBarH2 regulates the expression of CchiOBP6 , mediating the olfactory recognition of female Callosobruchus chinensis for 2,3‐butanediol. CchiBarH2 directly bound to the promoter region of CchiOBP6 and enhanced the transcriptional activity of CchiOBP6 in vitro using a dual‐luciferase reporter system and electrophoretic mobility shift assay (EMSA). RNAi‐mediated silencing of CchiBarH2 significantly decreased the expression level of CchiOBP6 , weakened the electrophysiological responses, and the attraction of C. chinensis females to 2,3‐butanediol disappeared simultaneously. CONCLUSION These results revealed that CchiBarH2 regulated the expression of CchiOBP6 , thereby mediating the EAG and behavioral responses of female C. chinensis to 2,3‐butanediol. These findings also provide potential molecular targets for disrupting olfactory‐driven behaviors in agricultural pest management.