1V3O:
reference: Crystal structures of a DNA octaplex with I-motif of G-quartets and its splitting into two quadruplexes suggest a folding mechanism of eight tandem repeats., Kondo J, Adachi W, Umeda S, Sunami T, Takenaka A, Nucleic Acids Res 2004 May 7;32(8):2541-9. Print 2004. PMID: 15133122

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