Coordinates growth and maturation by mediating endocrine responses to the attainment of critical weight during larval development. Plays a central role in the genetic cascades triggered by the steroid hormone ecdysone at the onset of metamorphosis, acting as both a repressor of the early ecdysone-induced regulatory genes and an inducer of the ftz-f1 midprepupal competence factor. During L2 and L3 stages, strong constitutive expression is seen in the ring gland. Lower expression is detected in specific neurons of the central nervous system (CNS) (at protein level). Flies exhibit larvae that precociously leave the food to form premature prepupae, resulting in abbreviated larval development that translates directly into smaller and lighter animals. Belongs to the nuclear hormone receptor family. NR1 subfamily.