POLB and infection: Complementation with the wild type Polβ cDNA, but not the empty vector, completely rescued infection efficiency (Figure 2F, Polβ−/− compared to Polβ−/− complemented with an empty expression vector p = 0.91, Polβ−/− compared to Polβ−/− complemented with a wild type Polβ transgene p<0.0001).