Poly/Mono-ADP Ribose (D9P7Z) Rabbit mAb #89190

ADP-ribosylation is involved in a variety of cellular processes, including mitotic spindle formation, chromatin decondensation, cell stress response, retroviral silencing, RNA biology, and transcription, but the most well-known function of ADP-ribose chains is to serve as a scaffold for recruiting DNA repair proteins that contain PAR-binding modules to sites of DNA damage (6). X-ray repair cross-complementing protein 1 (XRCC1), histone macroH2A1, the E3 ubiquitin ligase RNF146 (Iduna), and many of the PARPs themselves, among others, contain PAR-binding motifs (PBMs) or domains: WWE, PAR-binding zinc-finger (PBZ), or macrodomains (7). PARylation has a central role in cell survival, and is tightly regulated. PARP deficiency can leave a cell vulnerable to DNA damage-induced apoptosis, while hyper PARylation can lead to parthanatos, a unique form of cell death (8). The role of PARylation in DNA repair has inspired great interest in developing candidate drug inhibitors for PARP, in particular to treat breast, prostate, and small cell lung cancers with mutations in DNA repair genes like BRCA1/2, CHK2, or ATM. Stat1, PERK, p53, G-actin, and Ras are just a few examples of proteins that are functionally modulated by ADP-ribosylation (6,7). Modification by ADP-ribose can block protein interactions or, in the case of P2X7, cause a conformational change that, in the presence of ART2 expression, sensitizes naive murine T-cells to extracellular NAD+, leading to apoptosis (9).