AD293 cells were transfected with wild type or mutant K12-eGFP construct and each of the siRNAs: K12-Arg135Thr-5, -6, -8,-9,-13,-14 at a final concentration of 5 nM. To confirm the highly differential inhibitory effect of K12-Arg135Thr siRNA on mutant K12, western blot analysis was performed. When cells were treated with K12-Arg135Thr-5, the mutant K12-eGFP was almost completely knocked down, while expression of wild type K12 construct treated with the same siRNA showed a negligible reduction compared with NSC4 treatment. Wt = wild type and mut = mutant.