Fig. 4: The catalytic activity of TRDMT1 is vital for the suppression of PARP1 activation.

a Stable expression of Myc-tagged TRDMT1 in TRDMT1 KO U2OS-TRE cell lines shown in Western blots. Expression of β-actin is shown as control. The experiments were repeated independently three times with similar results. b U2OS-TRE TRDMT1 stably expressing cells transfected with TA-KR and GFP-PARP1 plasmids were light irradiated and allowed to recover for 0.5 h before fixation (scale bar: 10 μm). Fold increase of GFP-PARP1 foci intensity was quantified. Mean intensity of PARP1 at TA-KR /mean intensity of background is shown (n = 13 cells, Mean ± SEM). c U2OS-TRE TRDMT1 stably expressing cells transfected with TA-KR plasmid were light irradiated and allowed to recover for 0.5 h before fixation. Cells were stained with PAR antibody. Fold increase of PAR foci intensity was quantified. Mean intensity of PAR at TA-KR /mean intensity of background is shown (n = 13 cells, Mean ± SEM). d U2OS-TRE TRDMT1 stably expressing cells were irradiated with 2 Gy IR and were allowed for recover for 0.5 h. Cells with or without IR were collected and analyzed by Western blot for PAR level. The levels of PAR was quantified (n = 3 independent experiments, Mean ± SD). Statistical analysis was done with one-way ANOVA. Source data are provided as a Source Data file.