Sensitivity to phosphonoacetic acid: a new phenotype to probe DNA polymerase delta in Saccharomyces cerevisiae

Genetics. 2005 Jun;170(2):569-80. doi: 10.1534/genetics.104.040295. Epub 2005 Mar 31.


A mutant allele (pol3-L612M) of the DNA polymerase delta gene in Saccharomyces cerevisiae that confers sensitivity to the antiviral drug phosphonoacetic acid (PAA) was constructed. We report that PAA-sensitivity tagging DNA polymerases is a useful method for selectively and reversibly inhibiting one type of DNA polymerase. Our initial studies reveal that replication by the L612M-DNA pol delta requires Rad27 flap endonuclease activity since the pol3-L612M strain is not viable in the absence of RAD27 function. The L612M-DNA pol delta also strongly depends on mismatch repair (MMR). Reduced viability is observed in the absence of any of the core MMR proteins-Msh2, Mlh1, or Pms1-and severe sensitivity to PAA is observed in the absence of the core proteins Msh6 or Exo1, but not Msh3. We propose that pol3-L612M cells need the Rad27 flap endonuclease and MMR complexes composed of Msh2/Msh6, Mlh1/Pms1, and Exo1 for correct processing of Okazaki fragments.

Publication types

  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Adaptor Proteins, Signal Transducing
  • Alleles
  • Amino Acid Motifs
  • Base Pair Mismatch
  • Carrier Proteins / metabolism
  • Cell Survival
  • Culture Media
  • DNA Mutational Analysis
  • DNA Polymerase III / metabolism*
  • DNA Repair
  • DNA-Binding Proteins / metabolism
  • DNA-Directed DNA Polymerase / chemistry
  • Exodeoxyribonucleases / metabolism
  • Flap Endonucleases / metabolism
  • Fungal Proteins / chemistry
  • Fungal Proteins / metabolism
  • Genetic Techniques
  • MutL Protein Homolog 1
  • MutL Proteins
  • MutS Homolog 2 Protein / metabolism
  • Mutation
  • Phenotype
  • Phosphonoacetic Acid / pharmacology*
  • Polymerase Chain Reaction
  • Saccharomyces cerevisiae / enzymology*
  • Saccharomyces cerevisiae / genetics*
  • Saccharomyces cerevisiae Proteins / metabolism
  • Time Factors


  • Adaptor Proteins, Signal Transducing
  • Carrier Proteins
  • Culture Media
  • DNA-Binding Proteins
  • Fungal Proteins
  • MLH1 protein, S cerevisiae
  • MSH6 protein, S cerevisiae
  • PMS1 protein, S cerevisiae
  • Saccharomyces cerevisiae Proteins
  • DNA Polymerase III
  • DNA-Directed DNA Polymerase
  • Exodeoxyribonucleases
  • Flap Endonucleases
  • exodeoxyribonuclease I
  • RAD27 protein, S cerevisiae
  • MutL Protein Homolog 1
  • MutL Proteins
  • MutS Homolog 2 Protein
  • Phosphonoacetic Acid