2KZE:
reference: Coexistence of two distinct G-quadruplex conformations in the hTERT promoter., Lim KW, Lacroix L, Yue DJ, Lim JK, Lim JM, Phan AT, J Am Chem Soc. 2010 Sep 8;132(35):12331-42. PMID: 20704263

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