The differential binding of HMGB1a to the 22-bp duplexes with central TGGT, CGGA, or AGGC sequences (in the top strand) containing the single, site-specific 1,2-GG intrastrand CL of cisplatin, [Pt(R,R-DACH)]2+, or [Pt(S,S-DACH)]2+; the concentration of the duplex was 10 nM and the concentration of HMGB1a was in the range of 2–30 nM. (A) Representative gel showing binding of HMGB1a to the duplex with central TGGT sequence. (B) Bar graph illustrating Θ values (protein-bound duplex/total duplex ratio).