Regulation of eukaryotic genome stability using budding yeast as a model genetic system.
There are three major areas of focus within the lab: (1) defining the role of DNA damage in spontaneous mutagenesis, (2) understanding why transcription destabilizes the underlying DNA template, and (3) elucidating basic pathways of mitotic recombination. Studies are done in budding yeast and take advantage of the rapid and precise genome manipulation techniques available in this organism. Mutagenesis studies employ both standard forward mutation assays as well as highly sensitive reversion assays that detect specific types/classes of mutations. Specific interests include understanding how the cell deals with DNA damage that is encountered during replication and elucidating mechanisms of mutagenesis in nondividing cells. A major area of study focuses on the mutagenic effects of transcription, with a specific emphasis on topoisomerase I-dependent mutagenesis. Finally, mitotic recombination studies use a gap-repair assay together with diverged recombination substrates to define underlying strand exchange intermediates. Current analyses are focused on the roles of specialized DNA polymerases during recombination-associated DNA synthesis and on the roles of helicases in resolving recombination intermediates.