Co-localization in replication foci and interaction of human Y-family members, DNA polymerase polη and REV1 protein

The progress of replicative DNA polymerases along the replication fork may be impeded by the presence of lesions in the genome. One way to circumvent such hurdles involves the recruitment of specialized DNA polymerases that perform limited incorporation of nucleotides in the vicinity of the damaged site. This process entails DNA polymerase switch between replicative and specialized DNA polymerases. Five eukaryotic proteins can carry out translesion synthesis (TLS) of damaged DNA in vitro, DNA polymerases xi,eta,iota, and kappa, and REV1. To identify novel proteins that interact with hpoleta, we performed a yeast two-hybrid screen. In this paper, we show that hREV1 interacts with hpoleta as well as with hpolkappa and poorly with hpoliota. Furthermore, cellular localization analysis demonstrates that hREV1 is present, with hpoleta in replication factories at stalled replication forks and is tightly associated with nuclear structures. This hREV1 nuclear localization occurs independently of the presence of hpoleta. Taken together, our data suggest a central role for hREV1 as a scaffold that recruits DNA polymerases involved in TLS. (C) 2004 Elsevier B.V. All rights reserved.