Drosophila Oogenesis Apoptosis Assay

The starvation of Drosophila melanogaster females via deprivation of a suitable protein source triggers apoptosis at stage 8 of oogenesis (Terashima and Bownes 2004 (link)). To examine a possible co-occurrence of apoptosis and karyosome defects in wild-type (w¹¹¹⁸) females, they were starved on sucrose solution for an extended period of time. In this time course experiment, only recently eclosed females (within 16 h) were included. The young females were first matured on full cornmeal medium including yeast supplement for 46 h. The females were then kept in the presence of filter paper soaked with 10% sucrose solution for 8 h, 16 h, or 24 h prior to dissection and DAPI staining as described above. In oogenesis, the degradation process in apoptotic egg chambers can be followed using DNA staining (Etchegaray et al. 2012 (link)). To distinguish between non-apoptotic (phase 0–phase 1) and apoptotic (phase 2–phase 5) egg chambers at stage 8 of oogenesis, the classification published by Etchegaray et al. (2012 (link)) was followed. The stage of apoptotic egg chambers was thereby deduced from surrounding healthy egg chambers.