ABSTRACT
Poly(ADP-ribose) polymerase 1 (PARP-1), discovered more than 30 years ago, was thought until recently to be solely responsible for the synthesis of ADP-ribose polymers in animal cells. The recent identification of multiple proteins with PARP activity
dictates careful reevaluation of the roles of PARP-1 in cell death. Further, the newly discovered members of the PARP family need to be considered for potential involvement in cell death signaling pathways. All of the members of the PARP family have a catalytic domain that contains highly conserved residues referred to as a PARP signature sequence.
