View source for 6hkt


==Structure of an H1-bound 6-nucleosome array==
<StructureSection load='6hkt' size='340' side='right' caption='[[6hkt]], [[Resolution|resolution]] 9.70&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[6hkt]] is a 50 chain structure with sequence from [http://en.wikipedia.org/wiki/Human Human]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=6HKT OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=6HKT FirstGlance]. <br>
</td></tr><tr id='gene'><td class="sblockLbl"><b>[[Gene|Gene:]]</b></td><td class="sblockDat">HIST1H3A, H3FA, HIST1H3B, H3FL, HIST1H3C, H3FC, HIST1H3D, H3FB, HIST1H3E, H3FD, HIST1H3F, H3FI, HIST1H3G, H3FH, HIST1H3H, H3FK, HIST1H3I, H3FF, HIST1H3J, H3FJ ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=9606 HUMAN]), HIST1H4A, H4/A, H4FA, HIST1H4B, H4/I, H4FI, HIST1H4C, H4/G, H4FG, HIST1H4D, H4/B, H4FB, HIST1H4E, H4/J, H4FJ, HIST1H4F, H4/C, H4FC, HIST1H4H, H4/H, H4FH, HIST1H4I, H4/M, H4FM, HIST1H4J, H4/E, H4FE, HIST1H4K, H4/D, H4FD, HIST1H4L, H4/K, H4FK, HIST2H4A, H4/N, H4F2, H4FN, HIST2H4, HIST2H4B, H4/O, H4FO, HIST4H4 ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=9606 HUMAN]), HIST1H2AB, H2AFM, HIST1H2AE, H2AFA ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=9606 HUMAN]), HIST1H2BJ, H2BFR ([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=6hkt FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=6hkt OCA], [http://pdbe.org/6hkt PDBe], [http://www.rcsb.org/pdb/explore.do?structureId=6hkt RCSB], [http://www.ebi.ac.uk/pdbsum/6hkt PDBsum], [http://prosat.h-its.org/prosat/prosatexe?pdbcode=6hkt ProSAT]</span></td></tr>
</table>
== Function ==
[[http://www.uniprot.org/uniprot/H2B1J_HUMAN H2B1J_HUMAN]] 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.<ref>PMID:11859126</ref> <ref>PMID:12860195</ref> <ref>PMID:15019208</ref>   Has broad antibacterial activity. May contribute to the formation of the functional antimicrobial barrier of the colonic epithelium, and to the bactericidal activity of amniotic fluid.<ref>PMID:11859126</ref> <ref>PMID:12860195</ref> <ref>PMID:15019208</ref>  
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
Chromatin adopts a diversity of regular and irregular fiber structures in vitro and in vivo. However, how an array of nucleosomes folds into and switches between different fiber conformations is poorly understood. We report the 9.7 A resolution crystal structure of a 6-nucleosome array bound to linker histone H1 determined under ionic conditions that favor incomplete chromatin condensation. The structure reveals a flat two-start helix with uniform nucleosomal stacking interfaces and a nucleosome packing density that is only half that of a twisted 30-nm fiber. Hydroxyl radical footprinting indicates that H1 binds the array in an on-dyad configuration resembling that observed for mononucleosomes. Biophysical, cryo-EM, and crosslinking data validate the crystal structure and reveal that a minor change in ionic environment shifts the conformational landscape to a more compact, twisted form. These findings provide insights into the structural plasticity of chromatin and suggest a possible assembly pathway for a 30-nm fiber.

Structure of an H1-Bound 6-Nucleosome Array Reveals an Untwisted Two-Start Chromatin Fiber Conformation.,Garcia-Saez I, Menoni H, Boopathi R, Shukla MS, Soueidan L, Noirclerc-Savoye M, Le Roy A, Skoufias DA, Bednar J, Hamiche A, Angelov D, Petosa C, Dimitrov S Mol Cell. 2018 Oct 22. pii: S1097-2765(18)30798-6. doi:, 10.1016/j.molcel.2018.09.027. PMID:30392928<ref>PMID:30392928</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 6hkt" style="background-color:#fffaf0;"></div>
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Human]]
[[Category: Dimitrov, S]]
[[Category: Garcia-Saez, I]]
[[Category: Petosa, C]]
[[Category: Chromatin]]
[[Category: Chromatin fiber]]
[[Category: Dna binding protein]]
[[Category: Nucleosome array]]