Fig. 2.

(A) Left panel: Three representative reference-free 2D class averages corresponding to the M- and CID-subcomplexes. Middle panel: Re-projections of the corresponding crystal structures in the approximate orientations as shown in the left panel. Right panel: superposition of the crystal structure over the reference-free 2D classes (Brown-Sac3, Green-Thp1, Blue-Sem1, Red-Sus1, Yellow-Cdc31). (B) Overview of the 5.3 Å cryo-EM reconstruction of the M-region of TREX-2. (C) Examples of eight class averages corresponding to the M-subcomplex from the cryo-EM data. (D) Gold-standard FSC curve for the 3D density map after RELION post-processing. The resolution is estimated to be 5.3 Å by the gold-standard refinement criterion, as indicated by the dotted red line.