Fig. 6: EXO1 responds to formaldehyde-induced damage specifically.

a Left. IF staining against RPA2, RAD51 as well as cyclin A, and p53BP1 (pSer 1778) in RPE-1 WT and EXO1 KO (KO 7, KO 11) cells treated with 0 or 100 µM formaldehyde for 18 h. Right. Foci quantification performed in cyclin A or EdU positive cells. Data are shown with mean ± SEM from three independent experiments. ns: non-significant, *p < 0.1, **p < 0.01, and ****p  <  0.0001 (one-way ANOVA, followed by Kruskal–Wallis test). b Protein levels of EXO1, RPA32 (pSer4/Ser8) and RPA70 in RPE-1 WT and EXO1 KO (KO 7, KO 11) cells without treatment or treated with 100 µM formaldehyde for 18 h, with β-actin as a loading control. c Protein levels of EXO1 in RPE-1 WT cells with or without 1 mM formaldehyde treatment (30 min or 1 h), in either chromatin fraction (anti-histone H3) or non-chromatin fractions (α-tubulin). Quantification of the blots from three independent experiments is presented in Supplementary Fig. 6b. d Top. IF staining against pEXO1 (pSer 714) in S-phase determined by EdU staining in RPE-1 WT cells with or without 100 µM formaldehyde treatment for 18 h. Bottom. Foci quantification performed in EdU positive cells. Data are shown with mean ± SEM from three independent experiments. ****p < 0.0001 (one-way ANOVA, followed by Kruskal–Wallis test).