We will establish the novel action of JH and a new activator for ecdysone synthesis. We use the bamboo borer as an experimental animal, as JH will break larval diapause unlike other insect species. Taking advantage of this unusual feature of larval diapause, we will be able to find a totally new cascade of JH action at a molecular level. In addition, this proposal will provide DH as a novel stimulator for ecdysone synthesis. The knowledge obtain from this research will gain insight into the new concept how JH controls larval diapause in insects.