View source for 2aro


==Crystal Structure Of The Native Histone Octamer To 2.1 Angstrom Resolution, Crystalised In The Presence Of S-Nitrosoglutathione==
<StructureSection load='2aro' size='340' side='right'caption='[[2aro]], [[Resolution|resolution]] 2.10&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[2aro]] is a 8 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=2ARO OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=2ARO 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]] 2.1&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=CL:CHLORIDE+ION'>CL</scene>, <scene name='pdbligand=PO4:PHOSPHATE+ION'>PO4</scene></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=2aro FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=2aro OCA], [https://pdbe.org/2aro PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=2aro RCSB], [https://www.ebi.ac.uk/pdbsum/2aro PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=2aro ProSAT]</span></td></tr>
</table>
== 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.
== 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/ar/2aro_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=2aro ConSurf].
<div style="clear:both"></div>
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
A H3 dimer band is produced when purified native histone octamers are run on an SDS-PAGE gel in a beta-mercaptoethanol-free environment. To investigate this, native histone octamer crystals, derived from chicken erythrocytes, and of structure (H2A-H2B)-(H4-H3)-(H3'-H4')-(H2B'-H2A'), were grown in 2 M KCl, 1.35 M potassium phosphates and 250-350 microM of the oxidising agent S-nitrosoglutathione, pH 6.9. X-ray diffraction data were acquired to 2.10 A resolution, yielding a structure with an Rwork value of 18.6% and an Rfree of 22.5%. The space group is P6(5), the asymmetric unit of which contains one complete octamer. Compared to the 1.90 A resolution, unoxidised native histone octamer structure, the crystals show a reduction of 2.5% in the c-axis of the unit cell, and free-energy calculations reveal that the H3-H3' dimer interface in the latter has become thermodynamically stable, in contrast to the former. Although the inter-sulphur distance of the two H3 cysteines in the oxidised native histone octamer has reduced to 6 A from the 7 A of the unoxidised form, analysis of the hydrogen bonds that constitute the (H4-H3)-(H3'-H4') tetramer indicates that the formation of a disulphide bond in the H3-H3' dimer interface is incompatible with stable tetramer formation. The biochemical and biophysical evidence, taken as a whole, is indicative of crystals that have a stable H3-H3' dimer interface, possibly extending to the interface within an isolated H3-H3' dimer, observed in SDS-PAGE gels.

The oxidised histone octamer does not form a H3 disulphide bond.,Wood CM, Sodngam S, Nicholson JM, Lambert SJ, Reynolds CD, Baldwin JP Biochim Biophys Acta. 2006 Aug;1764(8):1356-62. Epub 2006 Jul 21. PMID:16920041<ref>PMID:16920041</ref>

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

==See Also==
*[[Histone 3D structures|Histone 3D structures]]
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Gallus gallus]]
[[Category: Large Structures]]
[[Category: Baldwin JP]]
[[Category: Lambert SJ]]
[[Category: Nicholson JM]]
[[Category: Reynolds CD]]
[[Category: Sodngam S]]
[[Category: Wood CM]]