poly (adp-ribose) polymerase 1 (parp-1) dna damage detection protein. target of cancer drug development

poly adp ribose polymerase parp dna repair programmed cell death parp1 caspase single strand break ssb par apoptosis lifespan longevity inhibitor cancer tumor nick talazoparib olaparib rucaparib veliparib ribosyltransferase podb4dqy structure peptide protein amino acid molecule polypeptide polymer atoms science scientific disease health molecular model