Caspase-independent cell engulfment mirrors cell death pattern in Drosophila embryos

• Published in: Development (Cambridge) Vol. 130; no. 23; pp. 5779 - 5789
• Main Authors: Mergliano, Jaime, Minden, Jonathan S
• Format: Journal Article
• Language: English
• Published: England The Company of Biologists Limited 01.12.2003
• Subjects: Acridine Orange - metabolism; Animals; beta-Galactosidase - metabolism; Biomarkers; Caspase Inhibitors; Caspases - metabolism; Cell Death - physiology; Drosophila melanogaster - anatomy & histology; Drosophila melanogaster - embryology; Drosophila melanogaster - genetics; Drosophila melanogaster - physiology; Endocytosis - physiology; Fluorescent Dyes - metabolism; Gene Expression Regulation, Developmental; Transgenes
• ISSN: 0950-1991; 1477-9129
• DOI: 10.1242/dev.00824

Programmed cell death plays an essential role during Drosophila embryonic development. A stereotypic series of cellular changes occur during apoptosis, most of which are initiated by a caspase cascade that is triggered by a trio of proteins, RPR, HID and GRIM. The final step in apoptosis is engulfment of the cell corpse. To monitor cell engulfment in vivo, we developed a fluorogenic β-galactosidase substrate that is cleaved by an endogenous, lysosomal β-galactosidase activity. The pattern of cell engulfment in wild-type embryos correlated well with the known pattern of apoptosis. Surprisingly, the pattern of cell engulfment persisted in apoptosis-deficient embryos. We provide evidence for a caspase-independent engulfment process that affects the majority of cells expected to die in developing Drosophila embryos.