Figure 1.

Cartoon representation, adapted from 17, of the main structural features of NPCs and conserved proteins between baker's yeast (Saccharomyces cerevisiae) and humans. The main structural components (RNA export platform, outer rings, membrane ring, inner rings, and nuclear basket, as well as the eight‐fold rotational symmetry of these structures) are conserved from yeast to humans 30. The outer rings are composed of Y‐shaped complexes; yeast NPCs have a total of two outer rings, one on the cytoplasmic and one on the nuclear side respectively. Humans have a total of four outer rings, two on the cytoplasmic side and two on the nuclear side. Human NPCs are considerably larger in their dimensions and their molecular mass (not shown) than yeast NPCs. The position of Nups within the NPC and their stoichiometry are best known in the yeast NPC (e.g., in 17, 31). Pom33, Nup2, Gle2, Dyn2 are dynamic or have prominent alternative locations or functions but also several bona fine Nups have roles away from the NPC. Most notably, the outer ring proteins Sec13 and Seh1 are also components of the COPII vesicle coat, and the membrane protein Ndc1 is also at the spindle pole body. Names of functional homologs within a structural component have the same color (e.g., the inner ring proteins Nic96‐Nup93, or Nup53‐Nup59‐Nup35). Nups that are unique for either yeast or human are written in orange font. #ELYS is only present in the outer rings at the nuclear side.