Figure 1

Putative ecdysone regulatory cascade in crustaceans. Ecdysone is secreted by the Y-organ, leading to its active form 20-hydroxyecdysone (20E). The heterodimer EcR/RXR receives 20E and initiates the transcription of the “early” response genes, which in turn regulates the transcription of “late” genes responsible for initiating molting and vitellogenesis. Modified from30.