RNA-Seq Analysis Reveals the Regulation of Fecundity by Aldehyde Oxidase TcAOX1 in Tribolium castaneum

Abstract Aldehyde oxidases (AOXs) play important roles in insects, including involvement in the detoxification of xenobiotics and the degradation of odorant signals. Previous studies have suggested that TcAOX1 may be involved in regulating the reproductive process of Tribolium castaneum. However, the precise mechanism by which TcAOX1 affects reproduction in T. castaneum remains unclear. Therefore, in this study, we established a control group and a TcAOX1 knockdown group, each with three biological replicates. Following the knockdown of TcAOX1 expression, RNA-Seq was performed. Differentially expressed genes (DEGs) were analyzed using Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses for functional annotation. In the GO analysis, eight genes were enriched in the catalytic activity term, and six genes were enriched in the metabolic process term. In the KEGG analysis, enrichment was observed across five categories: cellular processes, environmental information processing, human diseases, metabolism, and organismal systems. Following TcAOX1 knockdown, the expression of the aforementioned enriched genes—including serine protease P145 , serine protease P147 , serine protease P41 , and carboxypeptidase A —was downregulated. Additionally, the expression of cuticlin-2 , a cuticle protein gene implicated in the reproduction of T. castaneum , was also reduced. The downregulation of these genes may contribute to decreased oviposition rate and impaired embryonic development in T. castaneum . These findings suggest that TcAOX1 may influence reproduction in T. castaneum by modulating the expression of the above genes. This study provides a theoretical basis for research on reproduction in T. castaneum and offers new insights for the development of green pest control strategies against this species.