Relationship between 'early' and 'late' protein induced by 20-hydroxyecdysone in imaginal wing discs of Drosophila melanogaster.

The insect moulting hormone, 20-hydroxyecdysone, induces the synthesis of two groups of proteins in the imaginal wing discs of Drosophila melanogaster. The early induced group appears about 4 h after hormone treatment, the late induced group appears about 12 h after treatment. Studies using alpha-amanitin to inhibit mRNA synthesis during the period of hormonal treatment showed that the induction of the late proteins is dependent on mRNA synthesis and possibly the synthesis of the early proteins.