Fig. 5.

Model for the ring formation of the Nup84 complex. (A) Schematic representation of the heptameric complex and the approximate localization of its 7 nups (19). (B) The interaction of Nup120 and Nup133 suggests the intermolecular interaction between 2 heptamers in a head-to-tail fashion mediated by a short stretch at the very N terminus of an extended unstructured region of Nup133. (C) Eight heptamers are arranged in a closed ring with a diameter of ≈1,000 Å in accordance with the NPC dimensions determined by cryo-electron microscopy (8).