Thus, a multigenic approach was employed for the identification of other hepatopancreatic ecdysteroid-responsive genes by a cDNA microarray. For the purposes of this study, a multi-parametric molt-staging technique, based on X-ray detection of gastrolith growth,
was developed. To identify ecdysteroid-responsive genes during premolt, the molt cycle was induced by two manipulations, 20-hydroxyecdysone administration and Xorgan– sinus gland complex removal; both resulted in significant elevation of ecdysteroids. Two clusters of affected genes (129 and 122 genes, respectively) were revealed by the microarray.