Fig. 9
Circular dichroism (CD) spectra and quartz crystal microbalance (QCM) analysis for dsDNA–RNA triplex formation. a CD spectra of 1:1 mixtures of paired samples are shown in black. The sums of individual CD spectra of paired samples for controls are shown in red. Kd values were obtained from QCM measurements shown in Table 1. Kd, dissociation constant. b Schematic description of four types of dsDNA–RNA triplexes (I, II, III, and IV), classified into three levels of Kd values (10− 3, 10− 4–10− 5, and 10− 6–10− 7 M) from Table 1. The numbers in ellipsoids indicate the length or length range of the motifs (in nucleotides) in RNA and dsDNA oligomers. H, Hoogsteen base-pairing; rH, reverse Hoogsteen base-pairing. c Time courses of frequency changes of dsDNA-immobilized QCM in response to addition of RNA. Two each of the representative results from triplex types I to IV are shown. Negative controls were measured without immobilized dsDNA and recorded almost no change in QCM frequencies (data not shown)