Fig. 3. Pole cell death in N14^m– embryos might occur via a caspase 3-independent pathway. Pole cells in N14^m– embryos were directly labeled using a caged fluorescein (A, green), and were stained for cleaved caspase 3 (B, red) and Vasa (C, blue). (D) Merged image of A-C. Cleaved caspase 3 was never detected in the dying pole cells on the surface of the midgut, in which the fluorescein signal remained but the Vasa signal was reduced (arrowheads). Arrows indicate the active caspase 3-positive mis-migrated pole cells, which are usually seen even in wild-type embryos. Scale bar: 40 µm.