Characterization of murine Rad52 function in homologous recombination
Homologous recombination (HR) is an efficacious and conservative method of repairing double-strand breaks (DSBs). In yeast cells, the protein Rad52 is essential to HR. The experiments in this thesis were performed with the objective of determining the role of mammalian RAD52 in HR by testing the following hypothesis. The perturbation of murine Rad52 will affect the pathways of HR, specifically gene targeting, intrachromosomal recombination and DNA damage repair, in murine hybridoma cell lines. To test this hypothesis, hybridoma cells over-expressing Rad52 were assayed for gene targeting, DNA damage repair and intrachromosomal recombination, all of which was observed to be significantly stimulated in the presence of specific elevated concentrations of Rad52. To determine whether the phenotypes were due to combinatorial effects with Rad51, both Rad51 and Rad52 were over-expressed and observed to stimulate gene targeting to a greater degree than Rad52 over-expression alone, when the total protein concentrations of Rad51 and Rad52 were equal, while decreasing DNA damage resistance. These results indicate that Rad52 in combination with Rad51 is active in HR, specifically gene targeting and DNA damage repair.