Fig. 6. Apoptosis in salivary glands of sens^E2 embryos. (A-C) TUNEL staining in the salivary glands showed no apoptotic cells in the salivary glands of wild-type embryos. However, sens^E2 embryos showed presence of a large number of apoptotic cells that are absent in arm-GAL4: UAS-P35; sens^E2 embryos. Note the longer salivary glands in the arm-GAL4: UAS-P35; sens^E2 embryos compared with sens^E2 embryos. (D-G) reaper mRNA is not expressed in the salivary glands of stage 13 wild-type embryos but is upregulated in sens^E2 as well as arm-GAL4: UAS-P35; sens^E2 embryos. In sens^E2 embryos, reaper RNA disappears from the salivary glands at stage 14 (data not shown), whereas it continues to be expressed in the salivary glands of stage 15 arm-GAL4: UAS-P35; sens^E2 embryos (G). (H,I) Expression of hid is also induced in the salivary glands of sens^E2 embryos when compared with wild-type embryos.