Figure 5.

(A) The NER dual incision activity of CHO cells extract. Model DNAs were incubated for 30 min at 30°C with cell extracts prepared from CHO cells (20 nM model DNA, 0.3 or 1.6 mg/ml of extract proteins and 500 nM template 1).The excision products, containing nFlu, nAnt or Chol, were detected by annealing to a template followed by end-labelling using α-[³²P]-dCTP and Taq DNA polymerase. The reaction products were resolved on a 10% denaturing polyacrylamide gel. Non-modified 137-bp DNA was used as a negative control; ³²P-labelled oligonucleotides were used as size marker (lane M). (B) Relative signal of the target products for non-modified, nFlu– and nAnt–DNA after incubation with different concentrations of the extract proteins.