Fig 6.
Effect of RNAi-mediated down-regulation of DNA repair genes on ssODN-mediated gene targeting. Correction of the mutant neo gene by ssODN 3N in Msh2-deficient ES cells after transient down-regulation of various DNA repair genes by vector-mediated RNAi. Relative targeting efficiencies are the number of G418-resistant colonies per 105 cells that were plated after ssODN exposure, normalized to the efficiency found in empty vector (pS)-transfected control cells (black bars). Error bars represent the S.D. of at least three independent experiments. Expression levels of the various DNA repair genes were quantified by RT-PCR and normalized using mouse β-actin mRNA levels (grey bars). MMR, mismatch repair; HR, homologous recombination; NHEJ, non-homologous end joining; NER, nucleotide excision repair; TLS, translesion synthesis; PRR, post-replicative repair; DDR, DNA damage response.