Figure 4.

The tandem GQs in the telomeric overhang may adapt to different structures depending on how they interact with each other. Telomeric overhang formed by A) stacked GQs; B) partially stacked GQs; C) non-interacting GQs; and D) GQs with destabilizing interactions between neighboring structures. Fully stacked and destabilizing neighboring GQs are the two extremes of possible modes of interaction, with partial stacking and non-interacting models describing scenarios between these extremes. The noninteracting GQs are typically referred to as ‘beads on a string’; although, there is a certain level of loose terminology about this term in the literature. Depending on the level of folding, the GQs might adapt one or another of these models or may transition among them.