International Journal of Biological Macromolecules, 2023,https:// doi: 10.1016/j.ijbiomac.2023.128104  

Abstract

In biological control programs, knowledge about diapause regulation in natural enemy insects provides important insight for improving long-term storage, transportation, and field adoption of these biological control agents. As a natural predator of agricultural pests, the lady beetle  Coccinella septempunctata  has been commercially mass-cultured and widely employed in pest management. In some insects, insulin signaling, in conjunction with the downstream transcription factor Forkhead box O (FoxO), are master regulators of multiple physiological processes involved in diapause, but it is unclear whether insulin signaling and FoxO affect the diapause of  C. septempunctata . In this study, we use a combination of approaches to demonstrate that insulin signaling and FoxO mediate the diapause response in  C. septempunctata . In diapausing beetles, application of exogenous insulin and knocking down expression of  CsFoxo  with RNA interference (RNAi) both rescued beetles from developmental arrest. In non-diapausing beetles, knocking down expression of the  insulin receptor (CsInR)  with RNA interference (RNAi) arrested ovarian development and decreased juvenile hormone (JH) content to levels comparable to the diapause state. Taken together, these results suggest that a shutdown of insulin signaling prompts the activation of the downstream  FoxO  gene, leading to the diapause phenotypet.

International Journal of Biological Macromolecules,IF=8.2

https://pubmed.ncbi.nlm.nih.gov/37977460/