Fig. 6: FTO-PARP1 interaction, but not FTO demethylase activity, is required for the regulation of PARP1 function and DDR.

a Live imaging of FTO HeLa KO cells expressing GFP-PARP1 and myc-FTO (WT, Δ28 or DD) following UVA micro-irradiation. Scale bar, 5 μm. b and c Average (b) and normalized (c) traces of GFP-PARP1 fluorescence intensity changes over time. Solid and dashed lines indicate means and SEM, respectively. d and e Quantification of the peak fluorescent intensity (d) and the time-constant (τ) of fluorescence recovery after photobleaching (e) of GFP-PARP1 at DNA damage sites (KO, N = 11 cells; WT, N = 13; Δ28, N = 12; DD, N = 11). Data were analyzed using one-way ANOVA with Tukey’s multiple comparison test. f UVC-induced PARylation in FTO KO HeLa cells were transduced with or without lentiviral particles expressing myc-FTO (WT, Δ28 or DD). Total proteins were visualized by Revert Protein Stains on the PVDF membrane. g Quantification of total PAR levels. Data were normalized to the 1 min timepoint of the KO group (KO, N = 6; WT, N = 7; Δ28, N = 5; DD, N = 6) and analyzed using two-way ANOVA with Holm-Šídák’s multiple comparison test. h Dot-blot detection of the CPDs in genomic DNA of FTO KO HeLa cells expressing myc-FTO (WT, Δ28 or DD). Methylene blue showed the amount of DNA loaded onto the membrane. i Quantification of CPD levels. Data were normalized to the 1 min timepoint of the KO group (KO, N = 8; WT, N = 8; Δ28, N = 8; DD, N = 9) and analyzed using two-way ANOVA with Tukey’s multiple comparison test. j The percentage of cell survival was determined by quantifying the number of colonies and normalizing them to the non-irradiated control groups (KO, N = 9; WT, N = 8; Δ28, N = 9; DD, N = 8). Data were analyzed using two-way ANOVA with Tukey’s multiple comparison test. All data are represented as mean ± SEM. Source data are provided as a Source Data file.