One of the most common cellular responses to DNA breakage is the covalent post-translational modification of the nuclear proteins with poly ADP ribose from the NAD+ as a precursor, which is mostly catalyzed by the poly-ADP-ribose polymerase1(PARP1).

Keywords : NAD+, PARP, ADPr, Post Translational Modification, DNA base editing, DNA damage signaling, ARTs.