1. Tissue regeneration after radiation damage
More than half of cancer patients are treated with ionizing radiation. Therapeutic effect of IR is due to its ability to induce apoptosis. Surviving cells could, however, proliferate and regenerate the tumor leading to treatment failure. We have been using Drosophila melanogaster to identify and study mechanism by which cells survive radiation exposure and regenerate in the context of multicellular animals. We uncovered a mechanism for cell death in the absence of p53 that relies on E2F proteins (Wichmann et al., PNAS, 2006; Wichmann et al., Dev Bio, 2010). We found that surviving cells in the larval wing disc receive ‘do not die’ signals from dying cells (Bilak et al., PLoS Genetics, 2014). This signal also operates to protect Germline Stem Cells (Xing et al., Nat Comm, 2015). We identified a subset of columnar epithelial cells in the larval wing disc that relinquish their original fate to behave like stem cells after X-ray damage (Verghese and Su, PLoS Biology, 2016). We identified mechanisms that ensure that only one wing disc is regenerated, no more and no less (Verghese and Su, PLoS Genetics, 2017).