Induced 2 to 4 hours after treatment with 20-hydroxyecdysone (20E). Repressed by 8 hours after treatment with 20E, except in the presence of cycloheximide. Lacks the typical Glu active site in position 152 that is replaced by a Gln residue, preventing the hydrolase activity. Its precise function remains unclear. Belongs to the glycosyl hydrolase 18 family. IDGF subfamily.