ANALYSIS OF MUTAGENESIS IN UV-SENSITIVE MOUSE LYMPHOMA L5178Y-R CELLSWITH A POLYOMAVIRUS-BASED SHUTTLE VECTOR

A newly-developed polyomavirus-based shuttle vector, pPySLPT-2, was us ed to analyze mutations induced by UV radiation in the two related mou se lymphoma cell lines, L5178Y-R (LY-R) and L5178Y-S (LY-S). These wel l-studied cell lines differ in sensitivity to UV radiation, apparently due to differences in DNA repair capacity. Consistent with these diff erences, we found that replication of UV-irradiated vector is inhibite d to a greater extent in the UV sensitive LY-R cells than in the LY-S cells. Mutations were induced in the vector's supF target gene at a hi gher frequency in the LY-R cells than in the LY-S cells, but the seque nce characteristics of the base substitution mutations were similar in the two cell lines. The pattern of UV-induced mutations in the supF t arget gene of this polyomavirus-based vector, replicated in the mouse cells, was very similar to the pattern observed in the same target gen e in the analogous simian virus 40-based vector, pZ189, replicated in monkey and human cells.