4OGC:
reference: Structures of Cas9 Endonucleases Reveal RNA-Mediated Conformational Activation., Jinek M, Jiang F, Taylor DW, Sternberg SH, Kaya E, Ma E, Anders C, Hauer M, Zhou K, Lin S, Kaplan M, Iavarone AT, Charpentier E, Nogales E, Doudna JA, Science. 2014 Feb 6. PMID: 24505130

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