Schizosaccharomyces pombe Rtf2 mediates site-specific replication termination by inhibiting replication restart.
Here, we identify a phylogenetically conserved Schizosaccharomyces pombe factor, named Rtf2, as a key requirement for efficient replication termination at the site-specific replication barrier RTS1. We show that Rtf2, a proliferating cell nuclear antigen-interacting protein, promotes termination at RTS1 by preventing replication restart; in the absence of Rtf2, we observe the establishment of "slow-moving" Srs2-dependent replication forks. Analysis of the pmt3 (SUMO) and rtf2 mutants establishes that pmt3 causes a reduction in RTS1 barrier activity, that rtf2 and pmt3 are nonadditive, and that pmt3 (SUMO) partly suppresses the rtf2-dependent replication restart. Our results are consistent with a model in which Rtf2 stabilizes the replication fork stalled at RTS1 until completion of DNA synthesis by a converging replication fork initiated at a flanking origin.
Marie Curie Research Institute, The Chart, Oxted, Surrey RH8 0TL, United Kingdom.
Takabumi
T
Inagawa
Tomoko
T
Yamada-Inagawa
Trevor
T
Eydmann
I Saira
IS
Mian
Teresa S
TS
Wang
Jacob Z
JZ
Dalgaard
D020816:Amino Acid Motifs; D000595:Amino Acid Sequence; D004261:DNA Replication; D004268:DNA-Binding Proteins / Q000235:genetics / Q000502:physiology*; D005786:Gene Expression Regulation; D016681:Genome, Fungal; D008969:Molecular Sequence Data; D009154:Mutation; D010641:Phenotype; D010957:Plasmids / Q000378:metabolism; D018809:Proliferating Cell Nuclear Antigen / Q000378:metabolism; D012568:Schizosaccharomyces / Q000235:genetics / Q000378:metabolism*; D029702:Schizosaccharomyces pombe Proteins / Q000235:genetics / Q000502:physiology*; D017386:Sequence Homology, Amino Acid; D025841:Small Ubiquitin-Related Modifier Proteins / Q000378:metabolism; D020798:Two-Hybrid System Techniques
D004268:DNA-Binding Proteins; D018809:Proliferating Cell Nuclear Antigen; C541343:Rtf2 protein, S pombe; D029702:Schizosaccharomyces pombe Proteins; D025841:Small Ubiquitin-Related Modifier Proteins