Fig. 3. Overexpression of BR-Z3 during the critical feeding period for the second-to-third instar molt causes a prolonged second instar and the formation of L2 prepupae. (A) Second instar larvae were allowed to feed on standard diet for a designated period and were then transferred to glucose diet (protein starvation). Ecdysis to the third instar was scored. Each point (circle) represents a mean of four repetitions (N=16, 8, 8, 8) ± standard deviation (S.D.). Note the ET₅₀ for the critical feeding period is 6.5 h. (B) BR-Z3 was overexpressed by a heat shock at a designated time in the second instar, and the animals were maintained on the standard diet. The L2 prepupae were scored. Each point (diamond) represents a mean of four repetitions (N=25, 10, 10, 10) ± S.D. Note that the ET₅₀ of the induction of L2 prepupae is 5.8 h after ecdysis into the second instar.