(A) The isolated yeast NPC with a double outer ring segmented into proximal (gold) and distal (tan) rings. Density for Nup188/192 (red) and two orphans (silver) are shown. A double ring protomer is outlined (dashed box).
(B) Model of Y-complexes in the double outer ring with the overlaid density map.
(C) Top: three pairs of Y-complexes from the 3D density map. A gap is visible between neighboring Y-complexes in the distal ring (tan). Bottom: molecular models are shown in the map with MBMs indicated (*).
(D) Y-complexes from the distal (left) and proximal (center) outer rings are shown, along with a staggered pair (right). A torus-like bulge and Nup133 spur are present in the tails of distal and proximal Y-complexes, respectively.
(E) The pair of Y-complexes outlined in Figure 4A is shown with density for a Nup188/192 molecule (red) and three orphans (numbered 1–3). Orphans, MBMs(*), and a tripod of β-propellers are labeled. Scale bars are indicated on the panels.