Chromatin landscape changes of regenerating wing imaginal discs

We report the changes in chromatin accessibility associated with regeneration in wing imaginal discs at two developmental timepoints during L3. Wing discs were ablated using tissue-specific expression of the pro-apoptotic gene eiger at an early timepoint (day 7) when the discs retain high regenerative capacity and at a late time point (day 9) when regenerative capacity has significantly declined. ATAC-seq was performed on these discs after 40 hr of ablation and compared to identically staged unablated discs. We detect 14,142 open chromatin peaks after merging overlapping peaks from 3 biological repeats of all 4 conditions. Of these, 349 change significantly (log2fc>0.5, p<0.1) either opening or closing upon damage in early L3 discs, while only 55 open or close in late L3 discs. We describe two consequential groups of peak changes, those that are damage responsive (DR) in early L3 (222 peaks) and those that are maturity silenced (MS), open in early damaged L3 and closed in late damaged L3 (729 peaks). 28 peaks fall in the overlap of these two groups. Wing discs from early L3 (day 7@18'C) and late L3 (day 9 @18'C) unablated or ablated with egr for 40hrs (4 samples x 3 biological replicates each)