To further assess the level of completeness of our core network, we evaluated the average number of new interactions added to the core network with each new Y2H screen ( Figure 5B ). If core interactions indeed are conserved, as indicated by our predicted interactions, we would expect the coverage to increase with each new herpesviral interactome. Although the number of newly discovered interactions steadily decreased with each new screen, saturation does not seem to be reached yet. Thus, although coverage for the core network could be increased, a significant fraction of interactions might still be missing.