Maintenance of rhombomeres 3/5 labeling in Kaloop fish. (A–E) Expression of GFP in rhombomeres 3/5 in offspring from a cross between rh3/5:KalTA4 and 4xUAS-KGFPGI or (F-J) rh3/5:KalTA4 and 4xKaloop carriers (schematic representation of effector constructs shown). (A–C, F–H) Expression of mCherry and transactivated GFP at 26 hpf. (D) At 11 hpf, GFP fluorescence (red ovals) is diminished in 4xUAS-KGFP carriers and (E) lost in the adult brain, while in 4xKaloop carriers (I, J) it is maintained in 2 clusters in the hindbrain until adulthood (white arrows). (E, J) Sagittal sections at 100 μm, abbr.: see Fig. 4.