Fig. 4.

Scaffold architecture of the NPC [51]. The NPC is shown cut in half (a) four copies of the Y-complex per asymmetric unit of the NPC builds the scaffold of the cytoplasmic ring (CR) and the nucleoplasmic ring (NR). The outer copy is shown in orange; the inner copy is shown in gray. Multiple membrane contacts are apparent in the inner ring structure: density that contacts the outer leaf of the bilipid layer is shown in green and purple; apparent transmembrane domains are shown in blue. (b) Nup155 (green) appears to interact with the membrane at the points indicated in (a). (c) Six question mark densities (red) per asymmetric unit resembling the shapes of Nup205 or Nup188 localize to the CR, IR and NR. Another copy might reside only on the cytoplasmic site and is shown in orange. (d) Proteins of neighboring asymmetric units are shown as well.