Structure of the nuclear transport complex karyopherin-β2–Ran˙GppNHp

@article{Chook1999StructureOT,
  title={Structure of the nuclear transport complex karyopherin-$\beta$2–Ran˙GppNHp},
  author={Yuh Min Chook and G{\"u}nter Blobel},
  journal={Nature},
  year={1999},
  volume={399},
  pages={230-237}
}
Transport factors in the karyopherin-β (also called importin-β) family mediate the movement of macromolecules in nuclear–cytoplasmic transport pathways. Karyopherin-β2 (transportin) binds a cognate import substrate and targets it to the nuclear pore complex. In the nucleus, Ran˙GTP binds karyopherin-β2 and dissociates the substrate. Here we present the 3.0 Å structure of the karyopherin-β2–Ran˙GppNHp complex where GppNHp is a non-hydrolysable GTP analogue. Karyopherin-β2 contains eighteen HEAT… 
Structures of importins.
  • E. Conti
  • Biology
    Results and problems in cell differentiation
  • 2002
TLDR
The asymmetric distribution of cytoplasmic RanGDP and nuclear RanGTP drives the directionality of transport processes, ensuring cargo loading and cargo release in the appropriate cell compartments.
On a snailroad to the nucleus
The adoption of a twisted structure of importin-beta is essential for the protein-protein interaction required for nuclear transport.
TLDR
It was found that impbeta449 has a structural similarity with another nuclear migrating protein, namely beta-catenin, which is composed of another type of helix-repeated structure of ARM repeat, and the essential regions for NPC translocation for both importin-beta and beta- catenin are spatially well overlapped with one another.
Conformational Variability of Nucleo-cytoplasmic Transport Factors*
TLDR
It is revealed that binding of RanGTP/cargo to importin β, transportin, and Xpo-t triggers distinct conformational responses, suggesting that even closely related karyopherins employ different mechanisms of conformational regulation and that cargo and nuclear pore-interacting surfaces of the different receptors may be unique.
Karyopherin β2B participates in mRNA export from the nucleus
TLDR
The data support the conclusion that Kap β2B participates directly in the export of a large proportion of cellular mRNAs, and TAP connects Kapβ2B to the m RNAs to be exported.
The Importin β Binding Domain Modulates the Avidity of Importin β for the Nuclear Pore Complex*
TLDR
It is proposed that by controlling the degree of strain in the tertiary structure of importin β, the IBB domain modulates the affinity of the import complex for nucleoporins, thus dictating its persistence inside the NPC.
Structural basis for the nuclear protein import cycle.
  • M. Stewart
  • Biology, Chemistry
    Biochemical Society transactions
  • 2006
TLDR
Crystallography and biochemical and cellular studies have enabled a molecular description of the transport cycle to be developed and tested using protein engineering and computer modelling.
Molecular Basis for the Recognition of Snurportin 1 by Importin β*
TLDR
It is proposed that in vivo the synergy of Nup153 and nuclear RanGTP promotes translocation of uridine-rich ribonucleoproteins into the nucleus.
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