The role of novel genes rrp1(+) and rrp2(+) in the repair of DNA damage in Schizosaccharomyces pombe

DNA Repair (Amst). 2009 May 1;8(5):627-36. doi: 10.1016/j.dnarep.2008.12.008. Epub 2009 Jan 29.

Abstract

We identified two predicted proteins in Schizosaccharomyces pombe, Rrp1 (SPAC17A2.12) and Rrp2 (SPBC23E6.02) that share 34% and 36% similarity to Saccharomyces cerevisiae Ris1p, respectively. Ris1p is a DNA-dependent ATP-ase involved in gene silencing and DNA repair. Rrp1 and Rrp2 also share similarity with S. cerevisiae Rad5 and S. pombe Rad8, containing SNF2-N, RING finger and Helicase-C domains. To investigate the function of the Rrp proteins, we studied the DNA damage sensitivities and genetic interactions of null mutants with known DNA repair mutants. Single Deltarrp1 and Deltarrp2 mutants were not sensitive to CPT, 4NQO, CDPP, MMS, HU, UV or IR. The double mutants Deltarrp1 Deltarhp51 and Deltarrp2 Deltarhp51 plus the triple Deltarrp1 Deltarrp2 Deltarhp51 mutant did not display significant additional sensitivity. However, the double mutants Deltarrp1 Deltarhp57 and Deltarrp2 Deltarhp57 were significantly more sensitive to MMS, CPT, HU and IR than the Deltarhp57 single mutant. The checkpoint response in these strains was functional. In S. pombe, Rhp55/57 acts in parallel with a second mediator complex, Swi5/Sfr1, to facilitate Rhp51-dependent DNA repair. Deltarrp1 Deltasfr1 and Deltarrp2 Deltasfr1 double mutants did not show significant additional sensitivity, suggesting a function for Rrp proteins in the Swi5/Sfr1 pathway of DSB repair. Consistent with this, Deltarrp1 Deltarhp57 and Deltarrp2 Deltarhp57 mutants, but not Deltarrp1 Deltasfr1 or Deltarrp2 Deltasfr1 double mutants, exhibited slow growth and aberrations in cell and nuclear morphology that are typical of Deltarhp51.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Antineoplastic Agents, Alkylating / pharmacology
  • Cloning, Molecular
  • DNA Damage / drug effects
  • DNA Damage / physiology*
  • DNA Damage / radiation effects
  • DNA Repair / drug effects
  • DNA Repair / physiology*
  • DNA Repair / radiation effects
  • DNA, Fungal / physiology*
  • DNA-Binding Proteins / genetics*
  • DNA-Binding Proteins / metabolism*
  • Gamma Rays
  • Hydrogen Peroxide / pharmacology
  • Methyl Methanesulfonate / pharmacology
  • Mitomycin / pharmacology
  • Molecular Sequence Data
  • Mutation / genetics
  • Nucleic Acid Synthesis Inhibitors / pharmacology
  • Oxidants / pharmacology
  • Saccharomyces cerevisiae Proteins / genetics
  • Saccharomyces cerevisiae Proteins / metabolism
  • Schizosaccharomyces / genetics*
  • Schizosaccharomyces pombe Proteins / genetics
  • Schizosaccharomyces pombe Proteins / metabolism
  • Schizosaccharomyces pombe Proteins / physiology*
  • Sequence Homology, Amino Acid
  • Ultraviolet Rays

Substances

  • Antineoplastic Agents, Alkylating
  • DNA, Fungal
  • DNA-Binding Proteins
  • Nucleic Acid Synthesis Inhibitors
  • Oxidants
  • Rrp1 protein, S pombe
  • Rrp2 protein, S pombe
  • Saccharomyces cerevisiae Proteins
  • Schizosaccharomyces pombe Proteins
  • Mitomycin
  • Methyl Methanesulfonate
  • Hydrogen Peroxide