Identification and characterization of key genes in insulin signaling pathway as molecular targets for controlling the fall webworm, Hyphantria cunea

Background The insulin signaling pathway is closely related to metabolism, growth, reproductive capacity and lifespan of insects. However, the physiological function of the insulin signaling pathway is little known in Hyphantria cunea. Results Five insulin signaling pathway genes (HcInR, HcPI3K, HcAKT, HcFOXO and HcTOR) in H. cunea were identified and characterized in this study. The spatiotemporal expression profiles of the genes showed that HcInR, HcAKT, HcPI3K and HcTOR expressions were higher at the egg stage than those in other development stages, whereas HcFOXO was highly expressed in the adult stage; all of these genes were highly expressed in the larval digestive system, especially in the midgut and hindgut. After RNA interference (RNAi) of the five genes in 5(th) instar H. cunea larvae, weight gain and survival rate (except in the siHcAKT-injected group) were significantly decreased, and the developmental duration of larval and pupal stages were prolonged. In addition, knockdown of five genes in 7(th) instar larvae decreased the pupation rate, survival rate and oviposition capacity, and resulted in abnormal development during larval-pupal transition. Conclusion Our findings indicate that the insulin signaling pathway plays essential roles in growth and development and the molting process in H. cunea, providing an important basis for developing new potentially molecular targets for RNAi-based pest control and understanding the mechanism of H. cunea outbreak. (c) 2022 Society of Chemical Industry.

Automated summary

In this study, five genes in the insulin signaling pathway were identified and characterized in Hyphantria cunea. The expression profiles of these genes in different developmental stages and tissues were investigated. RNA interference experiments revealed that these genes play important roles in the growth, development, and molting process of H. cunea. The findings provide a valuable basis for developing RNAi-based pest control strategies and understanding the mechanism of H. cunea outbreaks.