Extended Data Fig. 3: Electron microscopy analysis of CasX–guide RNA–DNA ternary complex with a 30-bp target DNA.
From: CasX enzymes comprise a distinct family of RNA-guided genome editors
a, Target DNA sequence in this ternary complex. b, Electron microscopy analysis pipeline. From 7,500 drift-corrected micrographs, 1,698,815 particles were picked and used for 2D classification. By 2D-based manual screening, 713,219 good particles were selected for 3D classification into 4 classes. From the class that shows the most intact architecture, 363,431 particles were further used for heterogeneous refinement. This generated two reconstructions, state I and state II, which contained 71% and 29% of the particles, respectively. State I and state II were then independently refined to 3.8 Å and 4.2 Å, respectively. c, Euler angle distribution of the refined particles belonging to state I and state II. d, Gold-standard Fourier shell correlation (GSFSC) curve calculated using two independent half-maps. e, The density maps for both states, coloured by local resolution as calculated in Cryopsarc. The resolution ranges from 3 Å to 7 Å. c and d are taken directly from the standard output of Cryosparc.
