Figure 5. Potential G4 probability of the β^A G4#1 motif and of its mutants.

The 17-mer β^A G-rich motif can, in principle, fold into 10 intramolecular G4, formed by the stacking of three G-quartets. All 10 possibilities are shown. The runs of guanine residues involved in the G4 are highlighted in green. For each mutant, we defined the potential G4 (PG4) probability as the number of possible G4 divided by the number of possible G4 for the WT sequence (i.e., 10). According to the position of the single point mutation, the PG4 probability is 0 (for m3, m7, m11, m15, m16, and m17), 0.1 (for m2 and m12), 0.3 (for m6 and m8), 0.4 (for m1 and m13), 0.6 (for m4, m5, m9, and m10), and 1 (for m14). The studied point mutations are indicated by a red square and cover most of the different PG4 probabilities.