Fig. 2-. Ape1 stably binds the G4 oligonucleotides.

A) Representative native EMSA polyacrylamide gel of recombinant Ape1^WT (left) and Ape1^N∆33 (right). Binding on the indicated ODN substrates (25 nM) is shown. Poly dT-F was used as negative control whereas Nat was used as positive control. The difference between this signal and the corresponding sample in the left panel relies only the intensity. *, ** and *** indicate the signals derived from metastable complexes that display different migration. # indicates the formation of sovramolecular aggregates of telomeric oligonucleotides. Reactions were performed as explained in Materials and methods section.

B) Overlay of sensorgrams relative to SPR experiments for the binding to immobilized Biot- Nat of Ape1^WT (left) and Ape1^N∆33 (right), respectively.