DNA repair by a Rad22-Mus81-dependent pathway that is independent of Rhp51

Nucleic Acids Res. 2004 Oct 14;32(18):5570-81. doi: 10.1093/nar/gkh853. Print 2004.


In budding yeast most Rad51-dependent and -independent recombination depends on Rad52. In contrast, its homologue in fission yeast, Rad22, was assumed to play a less critical role possibly due to functional redundancy with another Rad52-like protein Rti1. We show here that this is not the case. Rad22 like Rad52 plays a central role in recombination being required for both Rhp51-dependent and -independent events. Having established this we proceed to investigate the involvement of the Mus81-Eme1 endonuclease in these pathways. Mus81 plays a relatively minor role in the Rhp51-dependent repair of DNA damage induced by ultraviolet light. In contrast Mus81 has a key role in the Rad22-dependent (Rhp51-independent) repair of damage induced by camptothecin, hydroxyurea and methyl-methanesulfonate. Furthermore, spontaneous intrachromosomal recombination that gives rise to deletion recombinants is impaired in a mus81 mutant. From these data we propose that a Rad22-Mus81-dependent (Rhp51-independent) pathway is an important mechanism for the repair of DNA damage in fission yeast. Consistent with this we show that in vitro Rad22 can promote strand invasion to form a D-loop that can be cleaved by Mus81.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • DNA Repair*
  • DNA, Fungal / chemistry
  • DNA, Fungal / genetics
  • DNA, Fungal / metabolism
  • DNA-Binding Proteins / deficiency
  • DNA-Binding Proteins / genetics
  • DNA-Binding Proteins / metabolism*
  • Endonucleases / deficiency
  • Endonucleases / genetics
  • Endonucleases / metabolism*
  • Models, Genetic
  • Mutation / genetics
  • Nucleic Acid Conformation
  • Rad51 Recombinase
  • Recombination, Genetic / genetics
  • Repetitive Sequences, Nucleic Acid / genetics
  • Saccharomyces cerevisiae Proteins
  • Schizosaccharomyces / genetics*
  • Schizosaccharomyces / metabolism*
  • Schizosaccharomyces pombe Proteins / genetics
  • Schizosaccharomyces pombe Proteins / metabolism*


  • DNA, Fungal
  • DNA-Binding Proteins
  • MUS81 protein, S pombe
  • RHP51 protein, S pombe
  • Saccharomyces cerevisiae Proteins
  • Schizosaccharomyces pombe Proteins
  • rad52 protein, S pombe
  • Rad51 Recombinase
  • Eme1 protein, S pombe
  • Endonucleases
  • MUS81 protein, S cerevisiae