View source for 2z5m


==Complex of Transportin 1 with TAP NLS, crystal form 2==
<StructureSection load='2z5m' size='340' side='right'caption='[[2z5m]], [[Resolution|resolution]] 3.00&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[2z5m]] is a 2 chain structure with sequence from [https://en.wikipedia.org/wiki/Homo_sapiens Homo sapiens]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2Z5M OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=2Z5M FirstGlance]. <br>
</td></tr><tr id='method'><td class="sblockLbl"><b>[[Empirical_models|Method:]]</b></td><td class="sblockDat" id="methodDat">X-ray diffraction, [[Resolution|Resolution]] 3&#8491;</td></tr>
<tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[https://proteopedia.org/fgij/fg.htm?mol=2z5m FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=2z5m OCA], [https://pdbe.org/2z5m PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=2z5m RCSB], [https://www.ebi.ac.uk/pdbsum/2z5m PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=2z5m ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/TNPO1_HUMAN TNPO1_HUMAN] Functions in nuclear protein import as nuclear transport receptor. Serves as receptor for nuclear localization signals (NLS) in cargo substrates. Is thought to mediate docking of the importin/substrate complex to the nuclear pore complex (NPC) through binding to nucleoporin 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 the importin, the importin/substrate complex dissociates and importin is re-exported from the nucleus to the cytoplasm where GTP hydrolysis releases Ran. 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 (By similarity). Involved in nuclear import of M9-containing proteins. In vitro, binds directly to the M9 region of the heterogeneous nuclear ribonucleoproteins (hnRNP), A1 and A2 and mediates their nuclear import. Appears also to be involved in hnRNP A1/A2 nuclear export. Mediates the nuclear import of ribosomal proteins RPL23A, RPS7 and RPL5. Binds to a beta-like import receptor binding (BIB) domain of RPL23A. In vitro, mediates nuclear import of H2A, H2B, H3 and H4 histones, and SRP19. In case of HIV-1 infection, binds and mediates the nuclear import of HIV-1 Rev. Mediates nuclear import of ADAR/ADAR1 (isoform 5) in a RanGTP-dependent manner.<ref>PMID:8986607</ref> <ref>PMID:9687515</ref> <ref>PMID:11682607</ref> <ref>PMID:19124606</ref> 
== Evolutionary Conservation ==
[[Image:Consurf_key_small.gif|200px|right]]
Check<jmol>
  <jmolCheckbox>
    <scriptWhenChecked>; select protein; define ~consurf_to_do selected; consurf_initial_scene = true; script "/wiki/ConSurf/z5/2z5m_consurf.spt"</scriptWhenChecked>
    <scriptWhenUnchecked>script /wiki/extensions/Proteopedia/spt/initialview01.spt</scriptWhenUnchecked>
    <text>to colour the structure by Evolutionary Conservation</text>
  </jmolCheckbox>
</jmol>, as determined by [http://consurfdb.tau.ac.il/ ConSurfDB]. You may read the [[Conservation%2C_Evolutionary|explanation]] of the method and the full data available from [http://bental.tau.ac.il/new_ConSurfDB/main_output.php?pdb_ID=2z5m ConSurf].
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== Publication Abstract from PubMed ==
Transportin 1 (Trn1) is a transport receptor that transports substrates from the cytoplasm to the nucleus through nuclear pore complexes by recognizing nuclear localization signals (NLSs). Here we describe four crystal structures of human Trn1 in a substrate-free form as well as in the complex with three NLSs (hnRNP D, JKTBP, and TAP, respectively). Our data have revealed that (1) Trn1 has two sites for binding NLSs, one with high affinity (site A) and one with low affinity (site B), and NLS interaction at site B controls overall binding affinity for Trn1; (2) Trn1 recognizes the NLSs at site A followed by conformational change at site B to interact with the NLSs; and (3) a long flexible loop, characteristic of Trn1, interacts with site B, thereby displacing transport substrate in the nucleus. These studies provide deep understanding of substrate recognition and dissociation by Trn1 in import pathways.

Structural basis for substrate recognition and dissociation by human transportin 1.,Imasaki T, Shimizu T, Hashimoto H, Hidaka Y, Kose S, Imamoto N, Yamada M, Sato M Mol Cell. 2007 Oct 12;28(1):57-67. PMID:17936704<ref>PMID:17936704</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
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<div class="pdbe-citations 2z5m" style="background-color:#fffaf0;"></div>

==See Also==
*[[Importin 3D structures|Importin 3D structures]]
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Homo sapiens]]
[[Category: Large Structures]]
[[Category: Hashimoto H]]
[[Category: Hidaka Y]]
[[Category: Imamoto N]]
[[Category: Imasaki T]]
[[Category: Kose S]]
[[Category: Sato M]]
[[Category: Shimizu T]]
[[Category: Yamada M]]