Figure 2.

Protein–protein interaction analyses between XRCC1 and BER proteins. The real-time protein–protein interaction kinetics of wild-type XRCC1 with polβ (A), ligase IIIα (B), and APTX (C) is measured by SPR assay where the interacting protein partner of XRCC1 was immobilized on CM5 biosensors. The ligand association and dissociation phases are shown for the protein concentration range of XRCC1 on the side of sensorgrams. D, table shows comparison of the equilibrium binding constants (KD) between XRCC1 wild-type and variants for polβ, ligase IIIα, and APTX. The protein–protein interaction kinetics for XRCC1 variants are presented in Figs. S3–S5.