The Nuclear Pore Complex (NPC) is a large protein complex embedded in the nuclear membrane that facilitates nucleocytoplasmic traffic. The NPC is composed of approximately 30 different proteins: the nucleoporins. The NPC displays 8-fold symmetry and each nucleoporin is present in multiple copies. From the central ring that forms the pore, filaments protrude into the cytoplasm (cytoplasmic filaments) and the nucleoplasm (nuclear basket). Many nucleoporins contain FG repeats which are thought to act as a diffusion barrier and docking sight for transport receptors (karyopherins). Export and import is controlled by the interaction of the karyopherins with localization and export sequences. (Adapted from FBrf0220062 and PMID:21495847).
xmas-2, drongo and RanBP3 listed in FBrf0219251 have not been included in the NUCLEAR PORE COMPLEX gene group. It seems likely that xmas-2 it associates with the NPC rather than being part of the complex (PMID:12411502). drongo contains FG repeats but is not a known NPC protein. RanBP3 is a cofactor for nuclear export.