The G-rich single-stranded telomeric DNA can adopt in vitro a variety of different non-B-DNA conformations such as an intramolecular quadruplex structure (G4-DNA).

• 端粒DNA序列在K~+、Na~+等离子的存在下能够形成稳定的G4-DNA结构,这种结构阻碍了端粒酶对端粒DNA引物的识别,从而抑制了端粒酶的表达。