View source for 9dch


==Single-stranded RNA-mediated PRC2 dimer==
<StructureSection load='9dch' size='340' side='right'caption='[[9dch]], [[Resolution|resolution]] 3.40&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[9dch]] is a 13 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=9DCH OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=9DCH 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]] 3.4&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=ZN:ZINC+ION'>ZN</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=9dch FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=9dch OCA], [https://pdbe.org/9dch PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=9dch RCSB], [https://www.ebi.ac.uk/pdbsum/9dch PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=9dch ProSAT]</span></td></tr>
</table>
== Disease ==
[https://www.uniprot.org/uniprot/EZH2_HUMAN EZH2_HUMAN] Weaver syndrome. The disease is caused by mutations affecting the gene represented in this entry.
== Function ==
[https://www.uniprot.org/uniprot/EZH2_HUMAN EZH2_HUMAN] Polycomb group (PcG) protein. Catalytic subunit of the PRC2/EED-EZH2 complex, which methylates 'Lys-9' (H3K9me) and 'Lys-27' (H3K27me) of histone H3, leading to transcriptional repression of the affected target gene. Able to mono-, di- and trimethylate 'Lys-27' of histone H3 to form H3K27me1, H3K27me2 and H3K27me3, respectively. Compared to EZH2-containing complexes, it is more abundant in embryonic stem cells and plays a major role in forming H3K27me3, which is required for embryonic stem cell identity and proper differentiation. The PRC2/EED-EZH2 complex may also serve as a recruiting platform for DNA methyltransferases, thereby linking two epigenetic repression systems. Genes repressed by the PRC2/EED-EZH2 complex include HOXC8, HOXA9, MYT1, CDKN2A and retinoic acid target genes. EZH2 can also methylate non-histone proteins such as the transcription factor GATA4 and the nuclear receptor RORA.<ref>PMID:14532106</ref> <ref>PMID:15385962</ref> <ref>PMID:15231737</ref> <ref>PMID:15225548</ref> <ref>PMID:16179254</ref> <ref>PMID:16618801</ref> <ref>PMID:16357870</ref> <ref>PMID:16936726</ref> <ref>PMID:17210787</ref> <ref>PMID:17344414</ref> <ref>PMID:19026781</ref> <ref>PMID:18285464</ref> <ref>PMID:20935635</ref> <ref>PMID:23063525</ref> 
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
Methyltransferase PRC2 (Polycomb Repressive Complex 2) introduces histone H3K27 trimethylation, a repressive chromatin mark, to tune the differential expression of genes. PRC2 is precisely regulated by accessory proteins, histone post-translational modifications and, notably, RNA. Research on PRC2-associated RNA has mostly focused on the tight-binding G-quadruplex (G4) RNAs, which inhibit PRC2 enzymatic activity in vitro and in cells. Our recent cryo-EM structure provided a molecular mechanism for G4 RNA inactivating PRC2 via dimerization, but it remained unclear how diverse RNAs associate with and regulate PRC2. Here, we show that a single-stranded G-rich RNA and an atypical G4 structure called pUG-fold unexpectedly also mediate near-identical PRC2 dimerization resulting in inhibition of PRC2 methyltransferase activity. The conformational flexibility of arginine-rich loops within subunits EZH2 and AEBP2 of PRC2 can accommodate diverse RNA secondary structures, resulting in protein-RNA and protein-protein interfaces similar to those observed previously with G4 RNA. Furthermore, we address a recent report that failed to detect PRC2-associated RNAs in living cells by demonstrating the insensitivity of PRC2-RNA interaction to photochemical crosslinking. Our results support the significance of RNA-mediated PRC2 regulation by showing that this interaction is not limited to a single RNA secondary structure, consistent with the broad PRC2 transcriptome containing many G-tract RNAs incapable of folding into G4 structures.

Diverse RNA Structures Induce PRC2 Dimerization and Inhibit Histone Methyltransferase Activity.,Song J, Yao L, Gooding AR, Thron V, Kasinath V, Cech TR bioRxiv [Preprint]. 2024 Aug 29:2024.08.29.610323. doi: , 10.1101/2024.08.29.610323. PMID:39257770<ref>PMID:39257770</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 9dch" style="background-color:#fffaf0;"></div>
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Homo sapiens]]
[[Category: Large Structures]]
[[Category: Kasinath VK]]
[[Category: Song JS]]