Figure 2.
(a) Oligonucleotide sequences and predicted secondary structures. The BBD internal loop is highlighted in red. Differences in sequence relative to BBD are shown in blue. (b) Formation of a higher-mobility BBD product upon platination of BBD. (c) Confirmation of cisplatin-induced cross-linking in BBD internal loop sequence, showing products of platinum treatment with (i) BBD, (ii) SBBD hybrid, and (iii) individual strands of SBBD. Conditions: (b) 0.2 μM 5′ 32P-labeled BBD treated with indicated concentrations of cisplatin for 1.5 h in deionized water, analyzed by 18% dPAGE, and visualized by autoradiograph; (c) 20 μM (0.2 nmol) RNA reacted with 10× cisplatin (200 μM) in 5 mM TEA (pH 7.8), 12–15 h, 37 °C, analyzed by 20% dPAGE, and visualized by staining with methylene blue.