Extended Data Fig. 6: Persistent PARP1 activation on the BER intermediates is a source of toxic PARP1 activity.
From: XRCC1 protects transcription from toxic PARP1 activity during DNA base excision repair
a, Representative images of the RNAPI foci (RPA194) and levels of global transcription (EU Immunofluorescence) in WT and XRCC1−/− RPE-1 cells following mock treatment or at the indicated times after treatment with 250 μM H2O2 for 5 min. b, Quantification of the RNAPI foci (RPA194) shown in (a). Data are means (±s.e.m.) of three independent experiments, and statistically significant differences were determined by two-way ANOVA with Sidak’s multiple comparisons test (p values are indicated). c and d, Immunoblot of PARP1 and/or ADP-ribose levels in total cell extract (panel c) and following ADP-ribose immunoprecipitation (panel d) prepared from WT and XRCC1−/− RPE-1 cells following mock treatment or at 2 h after treatment with 250 μM H2O2 for 5 min. Representative blots from one of three independent experiments are shown. e, Immunoblot of NTH1 in WT and XRCC1−/− RPE-1 cells treated for 72 h with 10 nM siRNA against NTH1. A representative blot from one of two independent experiments is shown.
