Nup358, a Cytoplasmically Exposed Nucleoporin with Peptide Repeats, Ran-GTP Binding Sites, Zinc Fingers, a Cyclophilin A Homologous Domain, and a Leucine-rich Region

• DOI: 10.1074/jbc.270.23.14209
• Publication Date: 2002-07-26T14:54:25Z
• Authors: Jian Wu; Michael J. Matunis; Doris Kraemer; Günter Blobel; Elias Coutavas
• Keywords: Ran; Nucleoporin

The Ras-related nuclear protein, Ran, has been implicated in transport. By screening a HeLa cell λ expression library with Ran-GTP and sequencing overlapping cDNA clones, we have obtained the derived primary structure of protein calculated molecular mass 358 kDa. Using antibodies raised against an expressed segment this punctate surface staining by immunofluorescence microscopy that is characteristic for nucleoporins. Electron immunogold-decorated rat liver envelopes sublocalized 358-kDa at (or near) tip cytoplasmic fibers pore complex (NPC). In agreement current convention, was therefore termed Nup358 (for nucleoporin kDa). contains leucine-rich region, four potential Ran binding sites (i.e. 1 homologous domains) flanked nucleoporin-characteristic FXFG or FG repeats, eight zinc finger motifs, C-terminal cyclophilin A domain. Consistent location NPC, found decoration Ran-gold only side NPC. Thus, first shown to contain two three soluble transport factors so far isolated, namely karyopherin Ran-GTP.