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1qgk

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Revision as of 10:18, 27 November 2019

STRUCTURE OF IMPORTIN BETA BOUND TO THE IBB DOMAIN OF IMPORTIN ALPHA

Structural highlights

1qgk is a 2 chain structure with sequence from Human. The January 2007 RCSB PDB Molecule of the Month feature on Importins by David S. Goodsell is 10.2210/rcsb_pdb/mom_2007_1. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance.
Resources:	FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT

Function

[IMB1_HUMAN] Functions in nuclear protein import, either in association with an adapter protein, like an importin-alpha subunit, which binds to nuclear localization signals (NLS) in cargo substrates, or by acting as autonomous nuclear transport receptor. Acting autonomously, serves itself as NLS receptor. Docking of the importin/substrate complex to the nuclear pore complex (NPC) is mediated by KPNB1 through binding to nucleoporin FxFG repeats and the complex is subsequently translocated through the pore by an energy requiring, Ran-dependent mechanism. At the nucleoplasmic side of the NPC, Ran binds to importin-beta and the three components separate and importin-alpha and -beta are re-exported from the nucleus to the cytoplasm where GTP hydrolysis releases Ran from importin. The directionality of nuclear import is thought to be conferred by an asymmetric distribution of the GTP- and GDP-bound forms of Ran between the cytoplasm and nucleus. Mediates autonomously the nuclear import of ribosomal proteins RPL23A, RPS7 and RPL5. Binds to a beta-like import receptor binding (BIB) domain of RPL23A. In association with IPO7 mediates the nuclear import of H1 histone. In vitro, mediates nuclear import of H2A, H2B, H3 and H4 histones. In case of HIV-1 infection, binds and mediates the nuclear import of HIV-1 Rev. Imports PRKCI into the nucleus.^[1] ^[2] ^[3] [IMA2_HUMAN] Functions in nuclear protein import as an adapter protein for nuclear receptor KPNB1. Binds specifically and directly to substrates containing either a simple or bipartite NLS motif. Docking of the importin/substrate complex to the nuclear pore complex (NPC) is mediated by KPNB1 through binding to nucleoporin FxFG repeats and the complex is subsequently translocated through the pore by an energy requiring, Ran-dependent mechanism. At the nucleoplasmic side of the NPC, Ran binds to importin-beta and the three components separate and importin-alpha and -beta are re-exported from the nucleus to the cytoplasm where GTP hydrolysis releases Ran from importin. The directionality of nuclear import is thought to be conferred by an asymmetric distribution of the GTP- and GDP-bound forms of Ran between the cytoplasm and nucleus.

Evolutionary Conservation

Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf.

Publication Abstract from PubMed

Cytosolic proteins bearing a classical nuclear localization signal enter the nucleus bound to a heterodimer of importin-alpha and importin-beta (also called karyopherin-alpha and -beta). The formation of this heterodimer involves the importin-beta-binding (IBB) domain of importin-alpha, a highly basic amino-terminal region of roughly 40 amino-acid residues. Here we report the crystal structure of human importin-beta bound to the IBB domain of importin-alpha, determined at 2.5 A and 2.3 A resolution in two crystal forms. Importin-beta consists of 19 tandemly repeated HEAT motifs and wraps intimately around the IBB domain. The association involves two separate regions of importin-beta, recognizing structurally distinct parts of the IBB domain: an amino-terminal extended moiety and a carboxy-terminal helix. The structure indicates that significant conformational changes occur when importin-beta binds or releases the IBB domain domain and suggests how dissociation of the importin-alpha/beta heterodimer may be achieved upon nuclear entry.

Structure of importin-beta bound to the IBB domain of importin-alpha.,Cingolani G, Petosa C, Weis K, Muller CW Nature. 1999 May 20;399(6733):221-9. PMID:10353244^[4]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.

References

↑ Jakel S, Gorlich D. Importin beta, transportin, RanBP5 and RanBP7 mediate nuclear import of ribosomal proteins in mammalian cells. EMBO J. 1998 Aug 3;17(15):4491-502. PMID:9687515 doi:10.1093/emboj/17.15.4491
↑ Jakel S, Albig W, Kutay U, Bischoff FR, Schwamborn K, Doenecke D, Gorlich D. The importin beta/importin 7 heterodimer is a functional nuclear import receptor for histone H1. EMBO J. 1999 May 4;18(9):2411-23. PMID:10228156 doi:10.1093/emboj/18.9.2411
↑ White WO, Seibenhener ML, Wooten MW. Phosphorylation of tyrosine 256 facilitates nuclear import of atypical protein kinase C. J Cell Biochem. 2002;85(1):42-53. PMID:11891849
↑ Cingolani G, Petosa C, Weis K, Muller CW. Structure of importin-beta bound to the IBB domain of importin-alpha. Nature. 1999 May 20;399(6733):221-9. PMID:10353244 doi:10.1038/20367

1 Structural highlights
2 Function
3 Evolutionary Conservation
4 Publication Abstract from PubMed
5 See Also
6 References

Proteopedia Page Contributors and Editors (what is this?)

OCA

Retrieved from "http://52.214.119.220/wiki/index.php/1qgk"

@@ Line 1: / Line 1: @@
 ==STRUCTURE OF IMPORTIN BETA BOUND TO THE IBB DOMAIN OF IMPORTIN ALPHA==
-<StructureSection load='1qgk' size='340' side='right' caption='[[1qgk]], [[Resolution|resolution]] 2.50&Aring;' scene=''>
+<StructureSection load='1qgk' size='340' side='right'caption='[[1qgk]], [[Resolution|resolution]] 2.50&Aring;' scene=''>
 == Structural highlights ==
 <table><tr><td colspan='2'>[[1qgk]] is a 2 chain structure with sequence from [http://en.wikipedia.org/wiki/Human Human]. The January 2007 RCSB PDB [http://pdb.rcsb.org/pdb/static.do?p=education_discussion/molecule_of_the_month/index.html Molecule of the Month] feature on ''Importins''  by David S. Goodsell is [http://dx.doi.org/10.2210/rcsb_pdb/mom_2007_1 10.2210/rcsb_pdb/mom_2007_1]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1QGK OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=1QGK FirstGlance]. <br>
@@ Line 27: / Line 27: @@
 </div>
 <div class="pdbe-citations 1qgk" style="background-color:#fffaf0;"></div>
+==See Also==
+*[[Importin 3D structures|Importin 3D structures]]
 == References ==
 <references/>
@@ Line 33: / Line 36: @@
 [[Category: Human]]
 [[Category: Importins]]
+[[Category: Large Structures]]
 [[Category: RCSB PDB Molecule of the Month]]
 [[Category: Cingolani, G]]

1qgk

From Proteopedia

Revision as of 10:18, 27 November 2019

STRUCTURE OF IMPORTIN BETA BOUND TO THE IBB DOMAIN OF IMPORTIN ALPHA

Structural highlights

Function

Evolutionary Conservation

Publication Abstract from PubMed

See Also

References

Contents

Proteopedia Page Contributors and Editors (what is this?)

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