PARP-1, a determinant of cell survival in response to DNA damage Véronique J. Bouchard, Michèle Rouleau, Guy G. Poirier  Experimental Hematology  Volume 31, Issue 6, Pages 446-454 (June 2003) DOI: 10.1016/S0301-472X(03)00083-3

Figure 1 Structure of PARP-1. PARP-1 can be divided in 3 main domains: a DNA-binding domain (DBD) with 2 zinc fingers (Zn I and Zn II), an automodification domain with a BRCT motif, and a catalytic domain with the NAD+-binding site. The nuclear localization signal (NLS) is located between the DBD and the automodification domain. It comprises the DEVD cleavage site recognized by caspases 3 and 7. Experimental Hematology 2003 31, 446-454DOI: (10.1016/S0301-472X(03)00083-3)

Figure 2 Model for DNA damage signaling by PARP-1. PARP-1 binds on DNA strand breaks and is activated. It then modifies factors to induce a cell cycle arrest and allow DNA repair. In case of massive DNA damage, PARP-1 can deplete the NAD+ pool and induce necrosis or send an apoptotic signal. Experimental Hematology 2003 31, 446-454DOI: (10.1016/S0301-472X(03)00083-3)