Novel initiator caspase reporters uncover previously unknown features of caspase-activating cells Luis Alberto Baena-Lopez Lewis Arthurton Marcus Bischoff Jean-Paul Vincent Cyrille Alexandre Reuben McGregor 10779/crick.12505406.v1 https://crick.figshare.com/articles/journal_contribution/Novel_initiator_caspase_reporters_uncover_previously_unknown_features_of_caspase-activating_cells/12505406 The caspase-mediated regulation of many cellular processes, including apoptosis, justifies the substantial interest in understanding all of the biological features of these enzymes. To complement functional assays, it is crucial to identify caspase-activating cells in live tissues. Our work describes novel initiator caspase reporters that, for the first time, provide direct information concerning the initial steps of the caspase activation cascade in Drosophila tissues. One of our caspase sensors capitalises on the rapid subcellular localisation change of a fluorescent marker to uncover novel cellular apoptotic events relating to the actin-mediated positioning of the nucleus before cell delamination. The other construct benefits from caspase-induced nuclear translocation of a QF transcription factor. This feature enables the genetic manipulation of caspase-activating cells and reveals the spatiotemporal patterns of initiator caspase activity. Collectively, our sensors offer experimental opportunities not available by using previous reporters and have proven useful to illuminate previously unknown aspects of caspase-dependent processes in apoptotic and non-apoptotic cellular scenarios. 2020-06-25 15:22:43 Apical caspase reporter Apoptotic nuclear migration Historical caspase reporter Interkinetic nuclear migration Non-apoptotic caspase functions Animals Apoptosis Caspases Cell Movement Cell Nucleus Cell Survival Cell Tracking Digestive System Drosophila Proteins Drosophila melanogaster Enzyme Activation Female Genes, Reporter Time Factors Time-Lapse Imaging Wings, Animal Vincent FC001204 06 Biological Sciences 11 Medical and Health Sciences