LAUSR

BACKGROUND Azadirachtin has the potential to be used for pest control. Nevertheless, few studies have investigated the effects of azadirachtin on the cognitive behavior of pests. In this study, the expression of the cAMP response element-binding protein (CREB) and its gene were studied via a series of experiments in the Spodoptera litura larvae that were treated with azadirachtin. RESULTS RNA-Seq analysis of S. litura larvae, which were treated with azadirachtin. According to the Kyoto Encyclopedia of Genes and Genomes analysis, the top 20 enriched pathways included the neuroactive ligand-receptor interaction pathways, with seven significantly differentially expressed genes that included CREB. The qRT-PCR result indicated that the CREB gene was expressed during the entire developmental stages of S. litura, where the relative expression of the CREB gene was significantly downregulated after treatment with azadirachtin. The grayscale statistical analysis also showed that the expression levels of protein kinase A (PKA), extracellular signal-regulated kinase (ERK) and the CREB proteins were significantly downregulated after treatment with azadirachtin. Moreover, the RNAi results showed that the azadirachtin effect on the cognitive behavior of S. litura was consistent with the effect on the cognitive behavior after interfering with CREB. In addition, the selectivity of the larvae to the addictive odor sources was reduced and the initial reaction time was increased. CONCLUSIONS This study clarified that azadirachtin can affect the cognitive behavior of S. litura and the treatment with azadirachtin resulted in a downregulation of the gene and the protein expression of CREB and its pathway proteins. This article is protected by copyright. All rights reserved.