PARP Mouse, Unlabeled, Clone: 42, BD

Poly(ADP-ribose) polymerase (PARP) is a constitutively expressed, abundant nuclear protein. It has been referred to as “a molecular nick sensor” due to its recognition of, and catalytic activation by, single or double strand DNA breaks. The most critical ad extensively studied role of PARP is its participation in DNA base excision repair. Following binding to damaged DNA, PARP uses NAD⁺ to synthesize branched polymers of poly(ADP-ribose) on nuclear target proteins, including itself. Such modification of PARP increases its negative charge and results in loss of interactionwith DNA due to electrostatic repulsion. This opens the damaged DNA to DNA repair proteins. The poly(ADP-ribose) molecule is quickly degraded by poly (ADP-ribose) glycohydrolase that is found in association with PARP. PARP contains N-terminal DNA-binding domain (DBD), a central automodification domain that accepts poly (ADP-ribose), and a C-terminal catalytic domain. PARP is one of the earliest proteins targeted by caspase-3 during apoptosis. Although this protein is central to DNA repair, it has additional DNA-related functions that remain to be investigated.

Immunofluorescence, Western Blotting