nuclear pore central transport channel

The central substructure of the nuclear pore complex (NPC), through which nucleocytoplasmic transport of RNAs, proteins and small molecules occurs. The central transport channel is filled with FG-nucleoporins, which form a selective barrier and provide a series of binding sites for transporter proteins. Characterized S. cerevisiae FG-nucleoporins include Nup159p, Nup145Np, Nup116p, Nup100p, Nsp1p, Nup57p, Nup49p, Nup42p, Nup53p, Nup59p/Asm4p, Nup60p and Nup1. Characterized vertebrate FG-nucleoporins include Nup214, Nup98, Nup62, Nup54, Nup58/45, NLP1, and Nup153.

nuclear pore linkers

A substructure of the nuclear pore complex (NPC) that serves to connect members of the central transport channel (composed of FG-nucleoporins) to the core scaffold (composed of the inner and outer NPC rings). In S. cerevisiae, the linkers are Nic96p and Nup82p. In vertebrates, they are Nup93 and Nup88. Components are arranged in 8-fold symmetrical 'spokes' around the central transport channel. Both linkers can be isolated in association with specific FG-nucleoporins, complexes that are sometimes referred to as the Nic96 complex (Nic96p-Nsp1p-Nup49p-Nup57p) and the Nup82 complex (Nup82p-Nup116p-Nup159p-Gle2p).

platelet alpha granule

A secretory organelle found in blood platelets, which is unique in that it exhibits further compartmentalization and acquires its protein content via two distinct mechanisms: (1) biosynthesis predominantly at the megakaryocyte (MK) level (with some vestigial platelet synthesis) (e.g. platelet factor 4) and (2) endocytosis and pinocytosis at both the MK and circulating platelet levels (e.g. fibrinogen (Fg) and IgG).