Defective interaction between Pol2p and Dpb2p, subunits of DNA polymerase epsilon, contributes to a mutator phenotype in Saccharomyces cerevisiae

Mutat Res. 2009 Oct 2;669(1-2):27-35. doi: 10.1016/j.mrfmmm.2009.04.012. Epub 2009 May 20.


Most of the prokaryotic and eukaryotic replicative polymerases are multi-subunit complexes. There are several examples indicating that noncatalytic subunits of DNA polymerases may function as fidelity factors during replication process. In this work, we have further investigated the role of Dpb2p, a noncatalytic subunit of DNA polymerase epsilon holoenzyme from Saccharomyces cerevisiae in controlling the level of spontaneous mutagenesis. The data presented indicate that impaired interaction between catalytic Pol2p subunit and Dpb2p is responsible for the observed mutator phenotype in S. cerevisiae strains carrying different mutated alleles of the DPB2 gene. We observed a significant correlation between the decreased level of interaction between different mutated forms of Dpb2p towards a wild-type form of Pol2p and the strength of mutator phenotype that they confer. We propose that structural integrity of the Pol epsilon holoenzyme is essential for genetic stability in S. cerevisiae cells.

Publication types

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

MeSH terms

  • Cell Survival
  • DNA Polymerase II / metabolism*
  • Gene Deletion
  • Immunoblotting
  • Mutagenesis
  • Mutation / genetics*
  • Phenotype
  • Protein Subunits
  • Saccharomyces cerevisiae / genetics*
  • Saccharomyces cerevisiae / growth & development
  • Saccharomyces cerevisiae Proteins / metabolism*
  • Two-Hybrid System Techniques


  • Protein Subunits
  • Saccharomyces cerevisiae Proteins
  • Dpb2 protein, S cerevisiae
  • DNA Polymerase II