The exonuclease activity of the yeast mitochondrial DNA polymerase γ suppresses mitochondrial DNA deletions between short direct repeats in Saccharomyces cerevisiae

Genetics. 2013 Jun;194(2):519-22. doi: 10.1534/genetics.113.150920. Epub 2013 Apr 15.


The importance of mitochondrial DNA (mtDNA) deletions in the progeroid phenotype of exonuclease-deficient DNA polymerase γ mice has been intensely debated. We show that disruption of Mip1 exonuclease activity increases mtDNA deletions 160-fold, whereas disease-associated polymerase variants were mostly unaffected, suggesting that exonuclease activity is vital to avoid deletions during mtDNA replication.

Keywords: Mip1; Pol Gamma; direct repeats; exonuclease; mtDNA deletions.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, N.I.H., Intramural

MeSH terms

  • DNA Polymerase I / genetics
  • DNA Polymerase I / metabolism*
  • DNA, Fungal / analysis
  • DNA, Mitochondrial / analysis*
  • Microsatellite Repeats / genetics*
  • Mitochondria / enzymology*
  • Mitochondria / genetics
  • Saccharomyces cerevisiae / enzymology
  • Saccharomyces cerevisiae / genetics
  • Saccharomyces cerevisiae / metabolism*
  • Saccharomyces cerevisiae Proteins / genetics
  • Saccharomyces cerevisiae Proteins / metabolism*
  • Sequence Deletion*


  • DNA, Fungal
  • DNA, Mitochondrial
  • Saccharomyces cerevisiae Proteins
  • DNA Polymerase I
  • MIP1 protein, S cerevisiae