Fig. 2

ARH3 mainly hydrolyzes ADP-ribosylated serines in vitro. a Number of ADP-ribosylated peptide spectra matches (PSMs) or demodified peptide spectra matches after PARG or ARH3 treatment. Data represent means ± SEM for n = 3 independent demodification experiments. b Venn diagrams of unique ADPr peptides and proteins. c Volcano plot of ARH3- and PARG-treated samples. “Unmodified peptides” are shown as open circles and “ADP-ribosylated peptides” as filled circles. ADP-ribosylation sites confirmed by EThcD spectra are annotated and color coded in red as S-ADPr and in blue as R-ADPr sites. ADP-ribosylated peptides with uncertain ADP-ribosylation site localization are shown in black. The black hyperbolic line represents a permutation-based false discovery rate (FDR) of 5% and a minimal fold change of 2. d Normalized abundance of individual Ser- and Arg-ADPr peptides after PARG or ARH3 treatment. Data represent means ± SEM for n = 3 independent demodification experiments