To address this issue, Wilde and colleagues hypothesized that microtubule reorganization may occur in Ran–GTP extracts, allowing for assembly of a spindle-like array. They examined movement of ...

The Ras-like small GTPase Ran and its regulators are also central to the movement of macromolecules through the NPC. All characterized importins bind to GTP-bound Ran (Ran-GTP), but not to Ran-GDP.