RP2 death requires ecdysteroid receptor function. (A, B) GFP labeling (green) and EcR immunoreactivity (red). At 10 h-APF, just prior to head eversion, both RP2s and aCCs exhibited low levels of nuclear EcR-A (A) and EcR-B1 (B). (C) In UAS-EcR-B1F645A (dominant-negative EcR-B1 mutation expressed in the neurons), RP2s were still present at 24 h-APF. (D) EcR139/EcRM554fs (EcR-A null mutation) animals showed normal RP2 death and aCC survival at 24 h-APF. Scale bars: 10 μm in (A, B); 20 μm in (C, D).