Mitochondrial DNA pp 59-72

Part of the Methods in Molecular Biology™ book series (MIMB, volume 554)

Functional Analysis of Mutant Mitochondrial DNA Polymerase Proteins Involved in Human Disease

  • Sherine S. L. Chan
  • William C. Copeland


DNA polymerase γ (pol γ) is the only DNA polymerase within the mitochondrion and is thus essential for replication and repair of mtDNA. POLG, the gene encoding the catalytic subunit of pol γ, is a major locus for a wide spectrum of mitochondrial diseases with more than 100 known disease mutations. Thus, we need to understand how and why pol γ defects lead to disease. By using an extensive array of methods, we are developing a clearer understanding of how defects in pol γ contribute to disease. Furthermore, crucial knowledge concerning the role of pol γ in mtDNA replication and repair can be acquired. Here we present the protocols to characterize mutant DNA pol γ proteins, namely, assays for processive DNA synthesis, exonuclease activity, DNA binding, subunit interaction, and protein stability.

Key words

DNA polymerase γ mitochondrial DNA polymerase DNA replication DNA repair mitochondrial disease enzyme assays POLG POLG2 


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Copyright information

© Humana Press, a part of Springer Science+Business Media, LLC 2009

Authors and Affiliations

  • Sherine S. L. Chan
    • 1
  • William C. Copeland
    • 1
  1. 1.Mitochondrial DNA Replication Group, Laboratory of Molecular Genetics, National Institute of Environmental Health SciencesNational Institutes of HealthUSA

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