Coordination of Rad1-Rad10 interactions with Msh2-Msh3, Saw1 and RPA is essential for functional 3' non-homologous tail removal

Nucleic Acids Res. 2018 Jun 1;46(10):5075-5096. doi: 10.1093/nar/gky254.


Double strand DNA break repair (DSBR) comprises multiple pathways. A subset of DSBR pathways, including single strand annealing, involve intermediates with 3' non-homologous tails that must be removed to complete repair. In Saccharomyces cerevisiae, Rad1-Rad10 is the structure-specific endonuclease that cleaves the tails in 3' non-homologous tail removal (3' NHTR). Rad1-Rad10 is also an essential component of the nucleotide excision repair (NER) pathway. In both cases, Rad1-Rad10 requires protein partners for recruitment to the relevant DNA intermediate. Msh2-Msh3 and Saw1 recruit Rad1-Rad10 in 3' NHTR; Rad14 recruits Rad1-Rad10 in NER. We created two rad1 separation-of-function alleles, rad1R203A,K205A and rad1R218A; both are defective in 3' NHTR but functional in NER. In vitro, rad1R203A,K205A was impaired at multiple steps in 3' NHTR. The rad1R218A in vivo phenotype resembles that of msh2- or msh3-deleted cells; recruitment of rad1R218A-Rad10 to recombination intermediates is defective. Interactions among rad1R218A-Rad10 and Msh2-Msh3 and Saw1 are altered and rad1R218A-Rad10 interactions with RPA are compromised. We propose a model in which Rad1-Rad10 is recruited and positioned at the recombination intermediate through interactions, between Saw1 and DNA, Rad1-Rad10 and Msh2-Msh3, Saw1 and Msh2-Msh3 and Rad1-Rad10 and RPA. When any of these interactions is altered, 3' NHTR is impaired.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • DNA Breaks, Double-Stranded
  • DNA End-Joining Repair
  • DNA Repair Enzymes / genetics
  • DNA Repair Enzymes / metabolism*
  • DNA-Binding Proteins / genetics
  • DNA-Binding Proteins / metabolism*
  • Endonucleases / genetics
  • Endonucleases / metabolism*
  • MutS Homolog 2 Protein / metabolism
  • MutS Homolog 3 Protein / genetics
  • MutS Homolog 3 Protein / metabolism
  • Mutation
  • Protein Interaction Mapping
  • Replication Protein A / genetics
  • Replication Protein A / metabolism*
  • Saccharomyces cerevisiae / genetics*
  • Saccharomyces cerevisiae / radiation effects
  • Saccharomyces cerevisiae Proteins / genetics
  • Saccharomyces cerevisiae Proteins / metabolism*
  • Single-Strand Specific DNA and RNA Endonucleases / genetics
  • Single-Strand Specific DNA and RNA Endonucleases / metabolism*
  • Ultraviolet Rays


  • DNA-Binding Proteins
  • MSH3 protein, S cerevisiae
  • MutS Homolog 3 Protein
  • RFA1 protein, S cerevisiae
  • Replication Protein A
  • Saccharomyces cerevisiae Proteins
  • Saw1 protein, S cerevisiae
  • Endonucleases
  • RAD1 protein, S cerevisiae
  • RAD10 protein, S cerevisiae
  • Single-Strand Specific DNA and RNA Endonucleases
  • MSH2 protein, S cerevisiae
  • MutS Homolog 2 Protein
  • DNA Repair Enzymes