Identification of a nuclear export receptor for tRNA

@article{Arts1998IdentificationOA,
  title={Identification of a nuclear export receptor for tRNA},
  author={G J Arts and Maarten Fornerod and lain W. Mattaj},
  journal={Current Biology},
  year={1998},
  volume={8},
  pages={305-314}
}
BACKGROUND Transport of macromolecules between the nucleus and cytoplasm of eukaryotic cells is mediated by nuclear import and export receptors. The receptors identified to date are members of a family of Ran GTPase-binding proteins whose founding member is importin-beta. Interaction between these receptors and their cargo is regulated by the GTP-bound form of Ran. Export complexes form and import complexes disassemble on binding of RanGTP to the receptor. Yeast Los 1 p is a member of the… 
Nuclear export of tRNA.
TLDR
Genetic studies in yeast have shown that Los1p/Xpo-t is not essential, unless additional steps in the tRNA biogenesis pathway are impaired, suggesting the existence of additional tRNA nuclear export routes.
Nuclear export of tRNA
  • G. Simos
  • Chemistry, Biology
    Protoplasma
  • 2005
TLDR
Genetic studies in yeast have shown that Los1p/Xpo-t is not essential, unless additional steps in the tRNA biogenesis pathway are impaired, suggesting the existence of additional tRNA nuclear export routes.
Importin-beta-like nuclear transport receptors
TLDR
Common features of all importin-β-like transport factors are their ability to shuttle between the nucleus and the cytoplasm, their interaction with RanGTP as well as their able to recognize specific transport substrates.
Functions of the GTPase Ran in RNA export from the nucleus.
TLDR
The GTPase of Ran does appear to be required in as yet unidentified intranuclear steps prior to export of some, but not all, RNAs.
Structures of the tRNA export factor in the nuclear and cytosolic states
TLDR
The binding mode explains how Xpot can recognize all mature tRNAs in the cell and yet distinguish them from those that have not been properly processed, thus coupling tRNA export to quality control.
Nuclear-Cytoplasmic Trafficking of NTF2, the Nuclear Import Receptor for the RanGTPase, Is Subjected to Regulation
TLDR
Evidence for the first time is provided that nucleocytoplasmic translocation of NTF2 is regulated in mammalian cells, and may involve a tyrosine and/or threonine kinase-dependent signal transduction mechanism(s).
Direct and Indirect Roles of Ran-GTP in Nuclear Export of RNAS in Higher Eukaryotes
TLDR
Two RNA export receptors that bind the export cargo in a Ran·GTP-dependent manner have been identified: Xpo-t (exportin-t), which binds directly to its tRNA export cargo, and CRM1 (Xpo-1 or exportin-1), which uses specific protein adapters to bind export cargos like snRNAs, certain cellular m RNAs, unspliced HIV-1 retroviral mRNA and rRNAs.
Exportin 4: a mediator of a novel nuclear export pathway in higher eukaryotes
TLDR
The Exportin 4 appears to be conserved amongst higher eukaryotes, but lacks obvious orthologues in yeast, and mediates nuclear export of eIF‐5A and possibly that of other cargoes.
Interactions between a Nuclear Transporter and a Subset of Nuclear Pore Complex Proteins Depend on Ran GTPase
TLDR
Data indicate that transport receptors such as Pse1p interact in a Ran-dependent manner with certain nucleoporins as it moves in or out of the nucleus via the NPC in order to understand how nuclear transporters traverse the NPC.
Exportin‐5‐mediated nuclear export of eukaryotic elongation factor 1A and tRNA
TLDR
This work has identified eukaryotic elongation factor 1A and tRNA as RanGTP‐dependent binding partners of exportin‐5 (Exp5), and shows that there exists an alternative tRNA export pathway which can be exploited to keep eEF1A out of the cell nucleus.
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TLDR
It is shown that p110 is CRM1, which is an evolutionarily conserved protein originally found as an essential nuclear protein in fission yeast and known as a likely target of LMB, which indicates that CRM 1 is an essential mediator of the NES-dependent nuclear export of proteins in eukaryotic cells.
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TLDR
It is reported that the previously identified CAS protein mediates importin alpha re-export and binds preferentially to NLS-free importinalpha, explaining why import substrates stay in the nucleus.
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TLDR
It is shown that nuclear import depends on cytoplasmic RanGDP and free GTP, and that RanGSP binds to the nuclear pore complex (NPC); therefore, import might involve nucleotide exchange and GTP hydrolysis on NPC‐bound Ran.
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TLDR
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TLDR
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TLDR
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TLDR
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TLDR
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TLDR
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