View source for 5gt0


==Crystal structure of nucleosome complex with human testis-specific histone variants, Th2a==
<StructureSection load='5gt0' size='340' side='right'caption='[[5gt0]], [[Resolution|resolution]] 2.82&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[5gt0]] is a 10 chain structure with sequence from [http://en.wikipedia.org/wiki/ ] and [http://en.wikipedia.org/wiki/Human Human]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=5GT0 OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=5GT0 FirstGlance]. <br>
</td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat"><scene name='pdbligand=CL:CHLORIDE+ION'>CL</scene>, <scene name='pdbligand=MN:MANGANESE+(II)+ION'>MN</scene></td></tr>
<tr id='related'><td class="sblockLbl"><b>[[Related_structure|Related:]]</b></td><td class="sblockDat">[[5gsu|5gsu]], [[5gt3|5gt3]]</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]), HIST1H2AA, H2AFR ([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=5gt0 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=5gt0 OCA], [http://pdbe.org/5gt0 PDBe], [http://www.rcsb.org/pdb/explore.do?structureId=5gt0 RCSB], [http://www.ebi.ac.uk/pdbsum/5gt0 PDBsum], [http://prosat.h-its.org/prosat/prosatexe?pdbcode=5gt0 ProSAT]</span></td></tr>
</table>
== Function ==
[[http://www.uniprot.org/uniprot/H2A1A_HUMAN H2A1A_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. 
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
Th2a and Th2b are the testis-specific histone variants highly expressed during spermatogenesis. Approximately 4% of the genome is retained in nucleosomes in mature human sperm, which is enriched at loci of developmental importance. Our recent studies revealed that the mouse histone variant homologs TH2a and TH2b are involved in reprogramming. In the present work, we report three nucleosome structures (NCPs) with human testis-specific histone variants hTh2a and hTh2b, [hGcH (hTh2a-hTh2b-H3-H4), hGcHV1 (hTh2a-H2b-H3-H4) and hGcHV2 (H2a-hTh2b-H3-H4)] and a 146-base pair (bp) duplex DNA fragment at ~3.0A resolutions. These crystal structures revealed two major changes within the nucleosomes, either with hTh2a, hTh2b or both variants, as compared to the canonical counterpart. First, the H-bonding interactions between the L1-L1' interfaces mediated by the hTh2a/hTh2a' L1-loops are lost. Second, the histone dimer-DNA contacts are considerably reduced, and these changes are localized around +/-31 to 35-bp from the nucleosome entry/exit sites. Thus, the modified functional residues at the N- and C-terminal ends of histone variants are responsible for the observed structural changes and regulate the gene expression through specific structural alterations in the chromatin by modulating the chromatin-associated binding proteins.

Structural analyses of the nucleosome complexes with human testis-specific histone variants, hTh2a and hTh2b.,Padavattan S, Thiruselvam V, Shinagawa T, Hasegawa K, Kumasaka T, Ishii S, Kumarevel T Biophys Chem. 2017 Feb;221:41-48. doi: 10.1016/j.bpc.2016.11.013. Epub 2016 Dec, 5. PMID:27992841<ref>PMID:27992841</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 5gt0" style="background-color:#fffaf0;"></div>

==See Also==
*[[Histone 3D structures|Histone 3D structures]]
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Human]]
[[Category: Large Structures]]
[[Category: Kumarevel, T]]
[[Category: Sivaraman, P]]
[[Category: Histone variant]]
[[Category: Ncp]]
[[Category: Nucleosome]]
[[Category: Structural protein-dna complex]]
[[Category: Testis-specifc]]
[[Category: Th2a]]