Fig. 4.

Determination of insertion repair efficiency and NHEJ rate at AAVS1 locus by restriction fragment length polymorphism assay, TA cloning and DNA sequencing. a and b show the enhancement of insertion repair by ssODN and SCR7 treatment in MCF-7 and HCT-116 cells as determined by restriction fragment length polymorphism assay. Genomic DNA was amplified by PCR, digested with EcoRI, and resolved in a 10% acrylamide gel. The original and cleaved DNA fragments are marked by arrows; the signals were quantified by densitometry; and the percentages of the cleaved fragments were calculated as described in “Methods”. c and d show the quantitation of insertion repair efficiency (%HDR), and Panels e and f show the percentages of NHEJ at AAVS1 locus by DNA sequencing of TA clones in MCF-7 and HCT-116 cells, respectively. Approximately 100 TA-clones were randomly picked up for DNA sequencing, and the insertion repair efficiency (%HDR) and NHEJ rate (%) in MCF-7 and HCT-116 cells was calculated based on DNA sequencing as described in the Methods. The data are the mean ± SD of three independent experiments. *p < 0.05, **p < 0.01 compared to the corresponding group without SCR7 (t test)