<i>Arabidopsis</i> PARPs respond to genotoxic stress.

<p>(A) Morphological and developmental defects of seedlings grown in increasing concentrations of MMS. Left panel: <i>parp1</i> and <i>parp2</i> single mutants. Right panel: <i>parp1 parp2</i> double mutants. <i>ku70</i> mutants were used as a positive control for MMS sensitivity. (B) qRT-PCR for <i>PARP</i> expression in wild type seedlings. Seedlings were either treated with 20 µM zeocin/0.6% DMSO or 0.6% DMSO (untreated) for 4 h. <i>PARP3</i> expression was not detected. * = p-value <0.005 compared to untreated.