Insulin/FoxO pathway synergies with juvenile hormones to promote the development of the reproductive system of Aspongopus chinensis

Abstract Aspongopus chinensis represents a significant insect species valued for its medicinal and nutritional properties. However, it undergoes a strict reproductive diapause that lasts for approximately 7 to 8 mo. The insulin/FoxO pathway is a highly conserved mechanism that is crucial for regulating protein, lipid, and carbohydrate metabolism, as well as influencing longevity, growth, development, and diapause in diverse animal species. In this study, exogenous insulin accelerated the development of the reproductive system of A. chinensis and eliminated diapause. Transcriptome sequencing revealed that the gene expression in diapausing individuals underwent significant alterations following the administration of exogenous insulin. A total of 81 genes demonstrated up-regulation, while 73 genes showed down-regulation in comparison to the control group. Among the array of differentially expressed genes, the gene encoding farnesol dehydrogenase, which plays a role in the synthesis of juvenile hormone (JH), was identified. Following the evaluation of JH levels, an increase was observed subsequent to the administration of insulin and the disruption of FoxO. The observations indicate a possible regulatory or influential function of insulin in the synthesis of JH, highlighting the collaborative role of both insulin/FoxO pathway and JH in the regulation of diapause in A. chinensis.