Figure 1

Illustration of triplex DNA structures and FRET pairs. (A) Randomly choosen polypurine sequence illustrating the orientation and sequence of antiparallel duplex, Hoogsteen type parallel triplexes and reverse Hoogsteen type antiparallel triplexes. (B) FRET pairs used for Watson-Crick antiparallel duplex formation and Hoogsteen parallel triplex formation with fluorophore name and brackets with excitation and emission maximum (nm). (C) Graphic presentation of the ATTO fluorophore FRET pair. Excitation and emission curves are shown for ATTO495 (left) and ATTO647N (right). Vertical lines demonstrate LightCycler laser excitation at 470 nm and detection channels at 530 and 670 nm. The graph is generated from spectral data obtained from http://www.ATTO-tec.com. Data was recorded by UV absorbance.