Interlocking G‑Quadruplexes\nUsing a G‑Triad•G\nConnection: Implications for G‑Wire Assembly

G-quadruplexes are\nnoncanonical structures of nucleic\nacids formed\nmainly by G-rich sequences and play crucial roles in important cellular\nprocesses. They are also increasingly used in nanotechnology for their\nvaluable properties. Various unexpected structures of G-quadruplexes\nhave been solved recently, including a stable G-quadruplex lacking\none guanine in the G-tetrad core, harboring a vacant site. In this\nstudy, we demonstrate the interlocking of two intramolecular G-quadruplexes:\none containing a vacant site (4<i>n</i> – 1) and\nthe other with an unbound guanine (4<i>n</i> + 1). These\nG-quadruplexes interact through a G-triad-G connection with unprecedented\n5′–3′ stacking. Using these interconnection properties,\nwe have identified a sequence capable of self-assembling into G-wires\nin K<sup>+</sup> solutions with potential nanotechnological applications.