Fig. 6. Averaged images of top and side views lead to the three-dimensional map of the nucleotide-free dynamin A* ring complex. (A) Averaged image of all 898 top views of nucleotide-free dynamin A* ring complexes at 25 Å resolution. The two concentric rings have an 11-fold symmetry. The inner and outer rings have averaged diameters of 18 and 26 nm, respectively. The inner ring forms spike-like structures towards the centre. (B) Averaged image of all 310 side views of nucleotide-free dynamin A* ring complexes. The side view has approximate 2-fold and mirror symmetry, and shows that the ring complex consists of two layers. At the periphery, the outer and inner ring are visible. (C) Three-dimensional map of the nucleotide-free dynamin A* ring complex reconstructed from top and side views. The scale bars in (A)–(C) all represent 10 nm.