title: Caspase-independent cell engulfment mirrors cell death pattern in Drosophila embryos.
abstract: 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 beta-galactosidase substrate that is cleaved by an endogenous, lysosomal beta-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.
authors.affiliation: Department of Biological Sciences and Science and Technology Center for Light Microscope Imaging and Biotechnology, Carnegie Mellon University, 4400 Fifth Avenue, Pittsburgh, PA 15213, USA.
authors.forename: Jaime
authors.initials: J
authors.lastname: Mergliano
authors.forename: Jonathan S
authors.initials: JS
authors.lastname: Minden
mesh_terms: D000165:Acridine Orange / Q000378:metabolism; D000818:Animals; D015415:Biomarkers; D061945:Caspase Inhibitors; D020169:Caspases / Q000378:metabolism*; D016923:Cell Death / Q000502:physiology*; D004331:Drosophila melanogaster / Q000033:anatomy & histology / Q000196:embryology* / Q000235:genetics / Q000502:physiology; D004705:Endocytosis / Q000502:physiology*; D005456:Fluorescent Dyes / Q000378:metabolism; D018507:Gene Expression Regulation, Developmental; D019076:Transgenes; D001616:beta-Galactosidase / Q000378:metabolism
chemical_list: D015415:Biomarkers; D061945:Caspase Inhibitors; D005456:Fluorescent Dyes; D001616:beta-Galactosidase; D020169:Caspases; D000165:Acridine Orange