Figure 2.
Representative cryo-EM structures of the compact, intermediate, and stretched conformations of the AP-3 complex. A–C, representative 2D class averages of the cryoDRGN classes corresponding to putative compact (A), intermediate (B), and stretched (C) conformation of the full-length AP-3 complex in solution. Scale bar: 5 nm. D–F, rotated side views of representative cryo-EM density maps of the compact (D), intermediate (E), and stretched (F) conformation of the AP-3 complex. The maps were segmented into the four subunits Apl5, Apl6, Apm3, and Aps3 that are depicted in blue, red, green, and gold, respectively. Segmented maps were generated in UCSF Chimera and are shown at different thresholds for visualization with thresholds of 0.016 for Apl5, 0.016 for Apl6, 0.0182 for Apm3, and 0.015 for Aps3. G–I, rotated side views of representative compact (G), intermediate (H), and stretched (I) AP-3 homology models generated by flexible fitting of trRosetta calculated structures of the four subunits into the 3D reconstructions.