Poly [ADP-ribose] polymerase 2 is an enzyme that in humans is encoded by the PARP2 gene.[5][6][7] It is one of the PARP family of enzymes.
This gene encodes poly(ADP-ribosyl)transferase-like 2 protein, which contains a catalytic domain and is capable of catalyzing a poly(ADP-ribosyl)ation reaction. This protein has a catalytic domain which is homologous to that of poly (ADP-ribosyl) transferase, but lacks an N-terminal DNA binding domain which activates the C-terminal catalytic domain of poly (ADP-ribosyl) transferase. The basic residues within the N-terminal region of this protein may bear potential DNA-binding properties, and may be involved in the nuclear and/or nucleolar targeting of the protein. Two alternatively spliced transcript variants encoding distinct isoforms have been found.[7]
In the plant species Arabidopsis thaliana, PARP2 plays more significant roles than PARP1 in protective responses to DNA damage and bacterial pathogenesis.[8] The plant PARP2 carries N-terminal SAP DNA binding motifs rather than the Zn-finger DNA binding motifs of plant and animal PARP1 proteins.[8]
Some PARP inhibitor anti-cancer drugs (primarily aimed at PARP1) also inhibit PARP2, e.g. niraparib.
PARP2 has been shown to interact with XRCC1.[9]