Establishment of a testing system for juvenoids that disturb the sex determination system of Daphnia, based on a molecular interaction of ligands and the JH receptor

Abstract

Bioassays are the most common method of evaluating toxic effects of chemicals on living organisms. However, since simple bioassays cannot provide information on mechanisms of toxic effects, it is also important to establish test methods that yield clear molecular evidence derived from the adverse outcome pathway. It is possible that chemicals bearing juvenile hormone activity (juvenoids) used as insect growth regulators may seriously impact population viability by disturbing sex determination mechanisms in freshwater microcrustaceans, like Daphnia, a keystone species in lake ecosystems. This review describes the molecular mechanism by which juvenoid disrupts the sex determination of daphnids and also introduces a simple testing method we recently developed for substances with juvenile hormone activity using juvenile hormone receptors.