Fig. 13. Gel-based analysis of substrate activities of NAD⁺, 48b, f and 45b, c for (A) PARP1; (B) PARP2; (C) catalytic domain of PARP5a; and (D) catalytic domain of PARP10. All the probes were successfully recognized by the corresponding enzymes, and the addition of PARP inhibitor olaparib efficiently inhibited the interactions between the probes and PARPs. Reproduced from ref. 131 with permission from Springer Nature, copyright 2019.