A family of Ran binding proteins that includes nucleoporins.
Ran, a small nuclear GTP binding protein, is essential for the translocation of nuclear proteins through the nuclear pore complex. We show that several proteins, including the Saccharomyces cerevisiae Nup2p and Caenorhabditis elegans F59A2.1 nucleoporins, contain domains similar to the previously characterized murine Ran binding protein (RBP, termed RBP1). To test the significance of this similarity, we have used the corresponding domains of Nup2p and a putative S. cerevisiae RBP in Ran binding assays and the yeast two-hybrid system. Both proteins bind S. cerevisiae Ran, but only the putative S. cerevisiae RBP binds human Ran. Two-hybrid analysis revealed Ran-Ran interactions and that yeast and human Rans can interact. These data identify Nup2p as a target for Ran in the nuclear pore complex, suggesting a direct role for it in nuclear-cytoplasmic transport. We discuss the possibility that proteins harboring Ran binding domains link the Ran GTPase cycle to specific functions in the nucleus.
Dingwall
C
C
Gene Expression Programme, European Molecular Biology Laboratory, Heidelberg, Germany.
Kandels-Lewis
S
S
Séraphin
B
B
D000595:Amino Acid Sequence; D000818:Animals; D002352:Carrier Proteins / Q000235:genetics / Q000378:metabolism*; D003001:Cloning, Molecular; D005656:Fungal Proteins / Q000235:genetics / Q000378:metabolism; D019204:GTP-Binding Proteins / Q000378:metabolism*; D006801:Humans; D008565:Membrane Proteins / Q000235:genetics / Q000378:metabolism*; D051379:Mice; D008969:Molecular Sequence Data; D009687:Nuclear Proteins / Q000235:genetics / Q000378:metabolism*; D016601:RNA-Binding Proteins / Q000235:genetics / Q000378:metabolism; D012441:Saccharomyces cerevisiae / Q000235:genetics / Q000378:metabolism; D017386:Sequence Homology, Amino Acid; D020931:ran GTP-Binding Protein
D002352:Carrier Proteins; D005656:Fungal Proteins; D008565:Membrane Proteins; D009687:Nuclear Proteins; D016601:RNA-Binding Proteins; C091775:ran-binding protein 1; D019204:GTP-Binding Proteins; D020931:ran GTP-Binding Protein