This entry represents the Ran-binding domain found in plant NUP50 protein. NUP50 is a nuclear pore complex component involved in nucleocytoplasmic transport via its interactions with importins and Ran [].
This entry represents a domain found in Nup2, 50 and 61, which are components of the nuclear pore complex. Nucleoporin 50kDa (NUP50) acts as a cofactor for the importin-alpha:importin-beta heterodimer, which in turn allows for transportation of many nuclear-targeted proteins through nuclear pore complexes. The C terminus of NUP50 binds importin-beta through RAN-GTP, the N terminus binds the C terminus of importin-alpha, while a central domain binds importin-beta. NUP50:importin-alpha:importin-beta then binds cargo and can stimulate nuclear import. The N-terminal domain of NUP50 is also able to actively displace nuclear localisation signals from importin-alpha []. NUP2 encodes a non-essential nuclear pore protein that has a central domain similar to those of Nsp1 and Nup1[, ]. Transport of macromolecules between the nucleus and the cytoplasm of eukaryotic cells occurs through the nuclear pore complex (NPC), a large macromolecular complex that spans the nuclear envelope [, , ]. The structure of the vertebrate NPC has been studied extensively; recent reviews include [, , , ]. The yeast NPC shares several features with the vertebrate NPC, despite being smaller and less elaborate [, ]. Many yeast nuclear pore proteins, or nucleoporins, have been identified by a variety of genetic approaches [, , , ]. nup2 mutants show genetic interactions with nsp1 and nup1 conditional alleles [, ]. Nup1 interacts with the nuclear import factor Srp1 []and with the small GTPase Ran (encoded by GSP1) [].
