This old version of Proteopedia is provided for student assignments while the new version is undergoing repairs. Content and edits done in this old version of Proteopedia after March 1, 2026 will eventually be lost when it is retired in about June of 2026.

Apply for new accounts at the new Proteopedia. Your logins will work in both the old and new versions.

5xbk

From Proteopedia

(Difference between revisions)

Jump to: navigation, search

Revision as of 14:10, 11 April 2018

Crystal structure of human Importin4

Structural highlights

5xbk is a 5 chain structure with sequence from African clawed frog and Human. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance.
Related:	5xah
Gene:	IPO4, IMP4B, RANBP4 (HUMAN)
Resources:	FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT

Function

[IPO4_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). Mediates the nuclear import of RPS3A. In vitro, mediates the nuclear import of human cytomegalovirus UL84 by recognizing a non-classical NLS.^[1]

Publication Abstract from PubMed

Importin4 transports histone H3/H4 in complex with Asf1a to the nucleus for chromatin assembly. Importin4 recognizes the nuclear localization sequence located at the N-terminal tail of histones. Here, we analyzed the structures and interactions of human Importin4, histones and Asf1a by cross-linking mass spectrometry (XL-MS), X-ray crystallography, negative-stain electron microscopy, small-angle X-ray scattering and integrative modeling. The XL-MS data showed that the C-terminal region of Importin4 was extensively crosslinked with the histone H3 tail. We determined the crystal structure of the C-terminal region of Importin4 bound to the histone H3 peptide, thus revealing that the acidic patch in Importin4 accommodates the histone H3 tail, and that histone H3 Lys14 contributes to the interaction with Importin4. In addition, we show that Asf1a modulates the binding of histone H3/H4 to Importin4. Furthermore, the molecular architecture of the Importin4_histone H3/H4_Asf1a complex was produced through an integrative modeling approach. Overall, this work provides structural insights into how Importin4 recognizes histones and their chaperone complex.

Integrative structural investigation on the architecture of human Importin4_histone H3/H4_Asf1a complex and its histone H3 tail binding.,Yoon J, Kim SJ, An S, Cho S, Leitner A, Jung T, Aebersold R, Hebert H, Cho US, Song JJ J Mol Biol. 2018 Jan 30. pii: S0022-2836(18)30041-X. doi:, 10.1016/j.jmb.2018.01.015. PMID:29408485^[2]

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

References

↑ Jakel S, Mingot JM, Schwarzmaier P, Hartmann E, Gorlich D. Importins fulfil a dual function as nuclear import receptors and cytoplasmic chaperones for exposed basic domains. EMBO J. 2002 Feb 1;21(3):377-86. doi: 10.1093/emboj/21.3.377. PMID:11823430 doi:http://dx.doi.org/10.1093/emboj/21.3.377
↑ Yoon J, Kim SJ, An S, Cho S, Leitner A, Jung T, Aebersold R, Hebert H, Cho US, Song JJ. Integrative structural investigation on the architecture of human Importin4_histone H3/H4_Asf1a complex and its histone H3 tail binding. J Mol Biol. 2018 Jan 30. pii: S0022-2836(18)30041-X. doi:, 10.1016/j.jmb.2018.01.015. PMID:29408485 doi:http://dx.doi.org/10.1016/j.jmb.2018.01.015

1 Structural highlights
2 Function
3 Publication Abstract from PubMed
4 References

Proteopedia Page Contributors and Editors (what is this?)

OCA

Retrieved from "http://52.214.119.220/wiki/index.php/5xbk"

@@ Line 3: / Line 3: @@
 <StructureSection load='5xbk' size='340' side='right' caption='[[5xbk]], [[Resolution|resolution]] 3.22&Aring;' scene=''>
 == Structural highlights ==
-<table><tr><td colspan='2'>[[5xbk]] is a 5 chain structure. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=5XBK OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=5XBK FirstGlance]. <br>
+<table><tr><td colspan='2'>[[5xbk]] is a 5 chain structure with sequence from [http://en.wikipedia.org/wiki/African_clawed_frog African clawed frog] and [http://en.wikipedia.org/wiki/Human Human]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=5XBK OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=5XBK FirstGlance]. <br>
 </td></tr><tr id='related'><td class="sblockLbl"><b>[[Related_structure|Related:]]</b></td><td class="sblockDat">[[5xah|5xah]]</td></tr>
+<tr id='gene'><td class="sblockLbl"><b>[[Gene|Gene:]]</b></td><td class="sblockDat">IPO4, IMP4B, RANBP4 ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=9606 HUMAN])</td></tr>
 <tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=5xbk FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=5xbk OCA], [http://pdbe.org/5xbk PDBe], [http://www.rcsb.org/pdb/explore.do?structureId=5xbk RCSB], [http://www.ebi.ac.uk/pdbsum/5xbk PDBsum], [http://prosat.h-its.org/prosat/prosatexe?pdbcode=5xbk ProSAT]</span></td></tr>
 </table>
@@ Line 22: / Line 23: @@
 __TOC__
 </StructureSection>
+[[Category: African clawed frog]]
+[[Category: Human]]
 [[Category: Song, J J]]
 [[Category: Yoon, J]]

5xbk

From Proteopedia

Revision as of 14:10, 11 April 2018

Crystal structure of human Importin4

Structural highlights

Function

Publication Abstract from PubMed

References

Contents

Proteopedia Page Contributors and Editors (what is this?)

Views

Personal tools

Navigation

Search

Toolbox