View source for 7v9s


==Telomeric trinucleosome in open state==
<StructureSection load='7v9s' size='340' side='right'caption='[[7v9s]], [[Resolution|resolution]] 11.00&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[7v9s]] is a 26 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=7V9S OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=7V9S 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]] 11&#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=7v9s FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=7v9s OCA], [https://pdbe.org/7v9s PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=7v9s RCSB], [https://www.ebi.ac.uk/pdbsum/7v9s PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=7v9s ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/H31_HUMAN H31_HUMAN] 
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
Telomeres, the ends of eukaryotic chromosomes, play pivotal parts in ageing and cancer and are targets of DNA damage and the DNA damage response(1-5). Little is known about the structure of telomeric chromatin at the molecular level. Here we used negative stain electron microscopy and single-molecule magnetic tweezers to characterize 3-kbp-long telomeric chromatin fibres. We also obtained the cryogenic electron microscopy structure of the condensed telomeric tetranucleosome and its dinucleosome unit. The structure displayed close stacking of nucleosomes with a columnar arrangement, and an unusually short nucleosome repeat length that comprised about 132 bp DNA wound in a continuous superhelix around histone octamers. This columnar structure is primarily stabilized by the H2A carboxy-terminal and histone amino-terminal tails in a synergistic manner. The columnar conformation results in exposure of the DNA helix, which may make it susceptible to both DNA damage and the DNA damage response. The conformation also exists in an alternative open state, in which one nucleosome is unstacked and flipped out, which exposes the acidic patch of the histone surface. The structural features revealed in this work suggest mechanisms by which protein factors involved in telomere maintenance can access telomeric chromatin in its compact form.

Columnar structure of human telomeric chromatin.,Soman A, Wong SY, Korolev N, Surya W, Lattmann S, Vogirala VK, Chen Q, Berezhnoy NV, van Noort J, Rhodes D, Nordenskiold L Nature. 2022 Sep;609(7929):1048-1055. doi: 10.1038/s41586-022-05236-5. Epub 2022 , Sep 14. PMID:36104563<ref>PMID:36104563</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 7v9s" style="background-color:#fffaf0;"></div>

==See Also==
*[[Histone 3D structures|Histone 3D structures]]
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Homo sapiens]]
[[Category: Large Structures]]
[[Category: Soman A]]