Figure 1.

APE1/Ref-1 has two distinct effects on DNA-binding activity of NF-κB p50. (A) NF-κB p50 (0.05 μM) was incubated with the indicated concentrations of GSH, Trx and APE1/Ref-1 WT either individually or in combination for 30 min, and then EMSA was performed with NF-κB probe. When Trx was used, 13–16 nM TrxR and 0.2 mM NADPH were also included in binding reactions. Where indicated, anti-APE1/Ref-1 or anti-Trx was included in the reactions. Asterisk indicates the APE1/Ref-1-DNA complex. (B) Schematic structure of APE1/Ref-1 WT and C/S. (C) EMSA were performed using APE1/Ref-1 C/S as in (A). (D) Protein–protein interactions of APE1/Ref-1 with p50. GST pull-down assays were performed as described in Materials and methods section.