6WCK:
reference: High resolution crystal structure of a KRAS promoter G-quadruplex reveals a dimer with extensive poly-A pi-stacking interactions for small-molecule recognition., Ou A, Schmidberger JW, Wilson KA, W Evans C, Hargreaves JA, Grigg M, O'Mara ML, Iyer KS, Bond CS, Smith NM, Nucleic Acids Res. 2020 Apr 20. pii: 5822969. doi: 10.1093/nar/gkaa262. PMID: 32313953

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