View source for 2xql


==Fitting of the H2A-H2B histones in the electron microscopy map of the complex Nucleoplasmin:H2A-H2B histones (1:5).==
<SX load='2xql' size='340' side='right' viewer='molstar' caption='[[2xql]], [[Resolution|resolution]] 19.50&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[2xql]] is a 10 chain structure with sequence from [https://en.wikipedia.org/wiki/Gallus_gallus Gallus gallus]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2XQL OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=2XQL FirstGlance]. <br>
</td></tr><tr id='method'><td class="sblockLbl"><b>[[Empirical_models|Method:]]</b></td><td class="sblockDat" id="methodDat">Electron Microscopy, [[Resolution|Resolution]] 19.5&#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=2xql FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=2xql OCA], [https://pdbe.org/2xql PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=2xql RCSB], [https://www.ebi.ac.uk/pdbsum/2xql PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=2xql ProSAT]</span></td></tr>
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== Function ==
[https://www.uniprot.org/uniprot/H2A4_CHICK H2A4_CHICK] Core component of nucleosome. Nucleosomes wrap and compact DNA into chromatin, limiting DNA accessibility to the cellular machineries which require DNA as a template. Histones thereby play a central role in transcription regulation, DNA repair, DNA replication and chromosomal stability. DNA accessibility is regulated via a complex set of post-translational modifications of histones, also called histone code, and nucleosome remodeling.
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== Publication Abstract from PubMed ==
Nucleoplasmin (NP) is a pentameric chaperone that regulates the condensation state of chromatin extracting specific basic proteins from sperm chromatin and depositing H2A-H2B histone dimers. It has been proposed that histones could bind to either the lateral or distal face of the pentameric structure. Here, we combine different biochemical and biophysical techniques to show that natural, hyperphosphorylated NP can bind five H2A-H2B dimers and that the amount of bound ligand depends on the overall charge (phosphorylation level) of the chaperone. Three-dimensional reconstruction of NP/H2A-H2B complex carried out by electron microscopy reveals that histones interact with the chaperone distal face. Limited proteolysis and mass spectrometry indicate that the interaction results in protection of the histone fold and most of the H2A and H2B C-terminal tails. This structural information can help to understand the function of NP as a histone chaperone.

Nucleoplasmin binds histone H2A-H2B dimers through its distal face.,Ramos I, Martin-Benito J, Finn R, Bretana L, Aloria K, Arizmendi JM, Ausio J, Muga A, Valpuesta JM, Prado A J Biol Chem. 2010 Oct 29;285(44):33771-8. Epub 2010 Aug 9. PMID:20696766<ref>PMID:20696766</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
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==See Also==
*[[Histone 3D structures|Histone 3D structures]]
== References ==
<references/>
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[[Category: Gallus gallus]]
[[Category: Large Structures]]
[[Category: Aloria K]]
[[Category: Arizmendi JM]]
[[Category: Ausio J]]
[[Category: Bretana L]]
[[Category: Finn R]]
[[Category: Martin-Benito J]]
[[Category: Muga A]]
[[Category: Prado A]]
[[Category: Ramos I]]
[[Category: Valpuesta JM]]