Extended Data Fig. 4: Cryo-EM analysis of Cas9:sgRNA.

a, Details of cryo-EM analysis. b, Unsharpened cryo-EM map (threshold 5σ) and model of Cas9:sgRNA in open-protein conformation. Green, NUC lobe; blue, REC lobe; orange, guide RNA; gray, unattributed density (REC1 or guide RNA, see Supplementary Information).