RNA Peach and Mango: orthogonal two-color fluorogenic aptamers distinguish nearly identical ligands

Effects of binding affinity by mutations in the Peach I GAA^A tetraloop-like motif. (A) Aligned sequences of Peach and Mango fluorogenic aptamers. For Peach I, G-residues predicted to participate in a G-quadruplex formation based on DMS probing data are shown in green. For Mango, G residues involved in quadruplex formation as determined by crystal structure are shown in blue. Stem regions are in gray, while GAA^A tetraloop motifs are indicated in pink. (B) Binding affinity measurements were performed testing the eight possible GNR^A type junction motifs in Peach I together with a potential UUC^G type motif.