PARP-1 protein interactions involved in DNA replication. In silico prediction from the protein-protein interaction databases of proteins with a specific function in the replication machinery. To provide maximal coverage of the potential interactome, results from four databases were compiled. These comprehensive database analyses revealed 52 proteins as potential interaction candidates with PARP-1(figure 4). These candidate proteins were further prioritized using searches based on two Gene Ontology keywords (DNA and replication), and 13 proteins were selected on the basis of their unique molecular functions. Further literature reviews identified the proteins in the DNA replication complex, Replication Factor Complex (RFC) complex. Proliferating Cell Nuclear Antigen (PCNA) has been shown to interact biochemically and/or genetically with PARP-1. In this way the potential interactions between PARP-1 and RFC1, 2, 3, 4, 5 was discovered. The solid lines represent direct protein interactions, and the dashed lines represent proteins found in a protein complex. The colour code is described in figure 4.