PARP: Proteins and Enzymes

PARP [Poly(ADP-ribose) Polymerase], also known as ADPRT and PPOL, is a 118-kDa enzyme that uses NAD as a substrate to catalyze the covalent transfer of ADP-ribose to a variety of nuclear protein acceptors. ADP ribosyltransferase is required for cellular repair, and PARP expression is induced by single-strand breaks in DNA. PARP is proteolytically cleaved by Caspase-3 into two fragments of 89- and 24-kDa in one of the hallmark events of apoptosis.