Detection of juvenile hormone-like function of diofenolan in Daphnia magna using in vivo short-term screening assay, TG211 Annex 7 reproduction test and microarray analysis

Juvenile hormone (JH) and JH agonists have been reported to induce male offspring production in various daphnids including Daphnia magna. We have recently established a short-term in vivo screening method to detect chemicals having JH activity, induction of male offspring, using adult D. magna. Diofenolan has been developed to be a JH agonist in insects, but no male induction in daphniids has been studied. In this study, we found the male offspring induction by diofenolan with a short-term in vivo screening method, and the most potent male offspring production activity among JH analogs studied using the OECD TG211 Annex 7. Transcriptome analysis of diofenolan-exposed D. magna showed up-regulation of JH-responsive genes. These results clearly demonstrated that diofenolan has JH activities in D. magna using the short-term in vivo screening assay, OECD TG211 Annex 7 and microarray analysis. Juvenile hormone agonists induced gene expression in daphnids neonates was measured at 48 hours after exposure to diofenolan (10 ng/L) and DMF as a control. Four independent experiments were performed at each chemicals.