title: ATP-dependent chromatin remodeling factors tune S phase checkpoint activity.
abstract: The S phase checkpoint response slows down replication in the presence of replication stress such that replication can resume normally once conditions are favorable. Both proper activation and deactivation of the checkpoint are crucial for genome stability. However, the mechanisms of checkpoint deactivation have been largely unknown. Here, we show that two highly conserved Saccharomyces cerevisiae ATP-dependent chromatin remodeling factors, Isw2 and Ino80, function to attenuate and deactivate S phase checkpoint activity. Genetic interactions revealed that these chromatin remodeling factors and the Rad53 phosphatases function in parallel in the DNA replication stress response. Following a transient replication stress, an isw2 nhp10 double mutant displays stronger and prolonged checkpoint activation without experiencing increased replication fork troubles. Isw2 and Ino80 are both enriched at stalled replication forks and physically and specifically interact with a single-stranded DNA binding protein, replication protein A (RPA). Based on these results, we propose that Isw2 and Ino80 are targeted to stalled replication forks via RPA and directly control the amplitude of S phase checkpoint activity and the subsequent deactivation process.
authors.affiliation: Basic Sciences Division, Fred Hutchinson Cancer Research Center, Seattle, Washington 98109, USA.
authors.forename: Tracey J
authors.initials: TJ
authors.lastname: Au
authors.forename: Jairo
authors.initials: J
authors.lastname: Rodriguez
authors.forename: Jack A
authors.initials: JA
authors.lastname: Vincent
authors.forename: Toshio
authors.initials: T
authors.lastname: Tsukiyama
mesh_terms: D000251:Adenosine Triphosphatases / Q000235:genetics / Q000378:metabolism*; D018797:Cell Cycle Proteins / Q000235:genetics / Q000378:metabolism; D064447:Checkpoint Kinase 2; D042002:Chromatin Assembly and Disassembly; D004260:DNA Repair; D004261:DNA Replication; D004268:DNA-Binding Proteins / Q000235:genetics / Q000378:metabolism; D006609:High Mobility Group Proteins / Q000235:genetics; D017346:Protein Serine-Threonine Kinases / Q000378:metabolism; D018741:Replication Origin; D051716:Replication Protein A / Q000378:metabolism; D059807:S Phase Cell Cycle Checkpoints; D012441:Saccharomyces cerevisiae / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D029701:Saccharomyces cerevisiae Proteins / Q000235:genetics / Q000378:metabolism*; D013312:Stress, Physiological; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism*
chemical_list: D018797:Cell Cycle Proteins; D004268:DNA-Binding Proteins; D006609:High Mobility Group Proteins; C483404:INO80 complex, S cerevisiae; C086468:ISWI protein; C529112:NHP10 protein, S cerevisiae; D051716:Replication Protein A; D029701:Saccharomyces cerevisiae Proteins; D014157:Transcription Factors; D064447:Checkpoint Kinase 2; D017346:Protein Serine-Threonine Kinases; C067022:RAD53 protein, S cerevisiae; D000251:Adenosine Triphosphatases