Ub-family modifications at the replication fork: Regulating PCNA-interacting components

► Many proteins compete for binding to PCNA during DNA replication. ► Modification to PCNA regulates protein interactions during replication and repair. ► Alternative clamp loading complexes can exchange PCNA at the replication fork. ► Replacing PCNA via degradation may regulate protein binding at thereplication fork. ► PCNA-dependent ubiquitination of interacting proteins promotes their degradation.