Eukaryotic initiation factor 5A (eIF-5A) is the only cellular protein known to contain the unusual amino acid hypusine. The exact in vivo function of eIF-5A, however, is to date unknown. The finding that eIF-5A is an essential cofactor of the human immunodeficiency virus type 1 (HIV-1) Rev RNA transport factor suggested that eIF-5A is part of a specific nuclear export pathway. In this study we used indirect immunofluorescence and immunogold electron microscopy to demonstrate that eIF-5A accumulates at nuclear pore-associated intranuclear filaments in mammalian cells and Xenopus oocytes. We are able to show that eIF-5A interacts with the general nuclear export receptor, CRM1. Furthermore, microinjection studies in somatic cells revealed that eIF-5A is transported from the nucleus to the cytoplasm, and that this nuclear export is blocked by leptomycin B. Our data demonstrate that eIF-5A is a nucleocytoplasmic shuttle protein.
Nuclear pore localization and nucleocytoplasmic transport of eIF-5A: evidence for direct interaction with the export receptor CRM1
- Views Icon Views
- PDF LinkPDF
- Share Icon Share
- Search Site
O. Rosorius, B. Reichart, F. Kratzer, P. Heger, M.C. Dabauvalle, J. Hauber; Nuclear pore localization and nucleocytoplasmic transport of eIF-5A: evidence for direct interaction with the export receptor CRM1. J Cell Sci 15 July 1999; 112 (14): 2369–2380. doi: https://doi.org/10.1242/jcs.112.14.2369
Download citation file: