sentence: ATR treatment resulted in activation of caspase-3 , releasing its 17 kDa active fragment ( p17 / p32 ; P < 0.01 versus CON ; Fig. 2E ) which further cleaved full length PARP1 ( 116 kDa ) to its inactive 89 kDa fragment ( p89 / p116 ; P < 0.01 versus CON ; Fig. 2E ) , thereby attenuating the DNA repair function of PARP1 [ 31 ] .