DNA damage signaling recruits the Rtt107-Slx4 scaffolds via Dpb11 to mediate replication stress response.
The DNA damage checkpoint kinase Mec1(ATR) is critical for maintaining the integrity of replication forks. Though it has been proposed to promote fork repair, the mechanisms by which Mec1 regulates DNA repair factors remain unclear. Here, we found that Mec1 mediates a key interaction between the fork protein Dpb11 and the DNA repair scaffolds Slx4-Rtt107 to regulate replication stress response. Dissection of the molecular basis of the interaction reveals that Slx4 and Rtt107 jointly bind Dpb11 and that Slx4 phosphorylation is required. Mutation of Mec1 phosphorylation sites in Slx4 disrupts its interaction with Dpb11 and compromises the cellular response to replisomes blocked by DNA alkylation. Multiple fork repair factors associate with Rtt107 or Slx4, supporting that Mec1-dependent assembly of the Rtt107-Slx4-Dpb11 complex functions to coordinate fork repair. Our results unveil how Mec1 regulates the Slx4 and Rtt107 scaffolds and establish a mechanistic link between DNA damage signaling and fork repair.
Ohouo
Patrice Y
PY
Graduate Program in Biochemistry, Molecular and Cell Biology, Weill Institute for Cell and Molecular Biology, Cornell University, 339 Weill Hall, Ithaca, New York 14853-7202, USA.
Bastos de Oliveira
Francisco M
FM
Almeida
Beatriz S
BS
Smolka
Marcus B
MB
D000478:Alkylation / Q000502:physiology; D018797:Cell Cycle Proteins / Q000235:genetics / Q000378:metabolism*; D004249:DNA Damage / Q000502:physiology*; D004260:DNA Repair / Q000502:physiology; D004261:DNA Replication / Q000502:physiology*; D004271:DNA, Fungal / Q000235:genetics / Q000378:metabolism*; D004706:Endodeoxyribonucleases / Q000235:genetics / Q000378:metabolism*; D047908:Intracellular Signaling Peptides and Proteins / Q000235:genetics / Q000378:metabolism; D046912:Multiprotein Complexes / Q000235:genetics / Q000378:metabolism*; D009687:Nuclear Proteins / Q000235:genetics / Q000378:metabolism*; D010766:Phosphorylation / Q000502:physiology; D017346:Protein Serine-Threonine Kinases / Q000235:genetics / Q000378:metabolism; D012441:Saccharomyces cerevisiae / Q000235:genetics / Q000378:metabolism*; D029701:Saccharomyces cerevisiae Proteins / Q000235:genetics / Q000378:metabolism*; D015398:Signal Transduction / Q000502:physiology
D018797:Cell Cycle Proteins; D004271:DNA, Fungal; C097185:DPB11 protein, S cerevisiae; D047908:Intracellular Signaling Peptides and Proteins; D046912:Multiprotein Complexes; D009687:Nuclear Proteins; C501265:RTT107 protein, S cerevisiae; D029701:Saccharomyces cerevisiae Proteins; C088937:MEC1 protein, S cerevisiae; D017346:Protein Serine-Threonine Kinases; D004706:Endodeoxyribonucleases; C505436:SLX4 protein, S cerevisiae