FRET Templated by G-Quadruplex DNA: A Specific Ternary Interaction Using an Original Pair of Donor/Acceptor Partners
journal contributionposted on 13.09.2006, 00:00 by Clémence Allain, David Monchaud, Marie-Paule Teulade-Fichou
G-quadruplex represents a suitable scaffold for FRET (fluorescence resonance energy transfer) since its two external quartets offer two well-defined binding sites for concomitant trapping of donor/acceptor partners. Combining selective G-quadruplex binders (macrocyclic bis(quinacridine) BOQ1 or monomeric quinacridine MMQ1, donor) with a highly fluorescent DNA probe (thiazole orange, acceptor), we designed a structure-specific FRET-system based on an unprecedented noncovalent ternary complex. This system could be potentially usable as a signature for quadruplex-DNA conformation in solution, but also might offer a unique means for observing cation and ligand binding influence on quadruplex topology.