. Whole-mount in situ hybridization was performed as described by Futahashi and Fujiwara (2005, 2008b). RNA probe for each gene was prepared using the DIG RNA Labeling Kit (Roche Biochemicals, Mannheim, Germany). Digoxigenin-labeled antisense RNA probes were used, and the color reaction was performed at room temperature in 100 mM Tris-HCl, 100 mM NaCl, and 50 mM MgCl2 (pH 9.5) containing 3.5 ml/ml 5-bromo-4-chloro-3-indolyl-phos- phate, 4-toluidine salt, and 4.5 ml/ml nitroblue tetrazolium chloride. Digoxigenin-labeled sense strand probes were used as negative controls. Sequence information about species-specific probes is shown in supporting information Table S2. Topical 20-hydro- xyecdysone (20E) application was performed as described by Fu- tahashi and Fujiwara (2007).