The Small GTPase Ran

1. The Role of Ran in Nuclear Import.- 1. Introduction.- 2. The Ran GTPase cycle and how it relates to nuclear protein import.- 3. Concluding remarks.- 4. References.- 2. Ran GTPase Regulation of the CRMl-Dependent Export Pathway.- 1. Introduction.- 2. Nuclear export signals.- 3. Identification of CRMl/exportin 1, the receptor for leucine-rich NES.- 4. Assembly of nuclear export complexes.- 5. Docking and translocation of the export complex through the NPC.- 6. Release of the export complex from the NPC.- 7. Concluding remarks.- 8. References.- 3. Role of Ran GTPase in RNA Processing and Export of RNA from the Nucleus to the Cytosol: Insights from Budding Yeast.- 1. Introduction.- 2. Ran pathway and tRNA biogenesis in S. cerevisiae.- 3. Ran and its role in ribosome biogenesis and nuclear export of ribosomes in S. cerevisiae.- 4. Ran and its role in nuclear export of mRNAs in S. cerevisiae.- 5. Concluding remarks.- 6. Acknowledgements.- 7. References.- 4. Direct and Indirect Roles of Ran·GTP in Nuclear Export of RNAs in Higher Eukaryotes.- 1. Introduction.- 2. Export of tRNA.- 3. Export of pre-snRNAs.- 4. Export of mRNAs.- 5. Export of ribosomal RNAs.- 6. Concluding remarks.- 7. Acknowledgements.- 8. References.- 5. The Role of Ran in Regulating Microtubule Spindle Assembly.- 1. Introduction.- 2. Studies that implicated Ran in the regulation of the microtubule cytoskeleton.- 3. Ran-GTP can stimulate microtubule spindle assembly in vitro.- 4. Generation of Ran-GTP by chromatin-bound RCC1 is required for spindle assembly.- 5. The molecular mechanism by which Ran regulates spindle assembly.- 6. Which spindle-forming processes does Ran regulate?.- 7. A model for how Ran-GTP regulates microtubule spindle assembly.- 8. Does Ran play a role in spindle assembly in vivo?.- 9.Could Ran-GTP have functions other than regulating spindle formation in mitosis?.- 10. Concluding remarks.- 11. Acknowledgements.- 12. References.- 6. Multiple Roles of the Ran GTPase During the Cell Cycle.- 1. Introduction.- 2. Expression of Ran pathway components in development and the cell cycle.- 3. Post-translational regulation of the Ran pathway.- 4. Ran’s role in regulation of the onset and completion of mitosis.- 5. Ran and mitotic spindle assembly.- 6. Ran and post-mitotic nuclear assembly.- 7. Concluding remarks, future directions.- 8. Acknowledgements.- 9. References.- 7. The Multiple Roles of Ran in the Fission Yeast Schizosac-charomyces pombe.- 1. Introduction.- 2. Introduction to the fission yeast S. pombe.- 3. Discovery of S. pombe Ran components.- 4. Localization of S. pombe Ran components.- 5. Phenotypic consequences of perturbing the Ran system.- 6. Evidence that the Ran system has multiple functions in fission yeast.- 7. Comparison of the phenotypic consequences of perturbing the Ran system in S. pombe and other experimental systems.- 8. Concluding remarks: Unanswered questions and future directions regarding the role of Ran in S. pombe.- 9. Acknowledgements.- 10. References.- 8. Mitotic Control by Ran and RanBPl in Mammalian Cells.- 1. Introduction.- 2. Mammalian RanBPl protein: structure and functions.- 3. Localization of components of the Ran network during the cell cycle.- 4.Spindle assembly in mammalian cells.- 5. Mitotic division.- 6. Nuclear reconstitution at mitotic exit.- 7. Concluding remarks.- 8. References.- 9. Ran Regulation by Ran GEF and Ran GAP.- 1. Introduction.- 2. Ran GEF stimulates guanine nucleotide exchange, and the resulting active Ran-GTP terminates import into the nucleus.- 3. In the cytoplasm, RanGAP induces Ran GTPaseactivity….- 4.…with some help from RanBP2 and RanBPl.- 5. Mogl induces release of GTP from Ran.- 6. Concluding remarks.- 7. References.- 10. Structural Views of the Ran GTPase Cycle.- 1. Introduction.- 2. Ran·GTP and Ran-GDP, active and inactive conformations.- 3. NTF2, a binding partner of Ran·GDP.- 4. Activation: RCC1 and its complex with Ran.- 5. Deactivation: Ran·GAP.- 6. Effectors of Ran.- 9. References.- 7. Concluding remarks.- 8. Acknowledgments.