3k26 is a 2 chain structure with sequence from Human. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance.
[EED_HUMAN] Polycomb group (PcG) protein. Component of the PRC2/EED-EZH2 complex, which methylates 'Lys-9' and 'Lys-27' of histone H3, leading to transcriptional repression of the affected target gene. Also recognizes 'Lys-26' trimethylated histone H1 with the effect of inhibiting PRC2 complex methyltransferase activity on nucleosomal histone H3 'Lys-27', whereas H3 'Lys-27' recognition has the opposite effect, enabling the propagation of this repressive mark. 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 and CDKN2A.[1][2][3][4][5][6][7][8][9]
Evolutionary Conservation
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Publication Abstract from PubMed
The polycomb repressive complex 2 (PRC2) is the major methyltransferase for H3K27 methylation, a modification critical for maintaining repressed gene expression programs throughout development. It has been previously shown that PRC2 maintains histone methylation patterns during DNA replication in part through its ability to bind to H3K27me3. However, the mechanism by which PRC2 recognizes H3K27me3 is unclear. Here we show that the WD40 domain of EED, a PRC2 component, is a methyllysine histone-binding domain. The crystal structures of apo-EED and EED in complex respectively with five different trimethyllysine histone peptides reveal that EED binds these peptides via the top face of its beta-propeller architecture. The ammonium group of the trimethyllysine is accommodated by an aromatic cage formed by three aromatic residues, while its aliphatic chain is flanked by a fourth aromatic residue. Our structural data provide an explanation for the preferential recognition of the Ala-Arg-Lys-Ser motif-containing trimethylated H3K27, H3K9, and H1K26 marks by EED over lower methylation states and other histone methyllysine marks. More importantly, we found that binding of different histone marks by EED differentially regulates the activity and specificity of PRC2. Whereas the H3K27me3 mark stimulates the histone methyltransferase activity of PRC2, the H1K26me3 mark inhibits PRC2 methyltransferase activity on the nucleosome. Moreover, H1K26me3 binding switches the specificity of PRC2 from methylating H3K27 to EED. In addition to determining the molecular basis of EED-methyllysine recognition, our work provides the biochemical characterization of how the activity of a histone methyltransferase is oppositely regulated by two histone marks.
Binding of different histone marks differentially regulates the activity and specificity of polycomb repressive complex 2 (PRC2).,Xu C, Bian C, Yang W, Galka M, Ouyang H, Chen C, Qiu W, Liu H, Jones AE, Mackenzie F, Pan P, Li SS, Wang H, Min J Proc Natl Acad Sci U S A. 2010 Oct 25. PMID:20974918[10]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
↑Sewalt RG, van der Vlag J, Gunster MJ, Hamer KM, den Blaauwen JL, Satijn DP, Hendrix T, van Driel R, Otte AP. Characterization of interactions between the mammalian polycomb-group proteins Enx1/EZH2 and EED suggests the existence of different mammalian polycomb-group protein complexes. Mol Cell Biol. 1998 Jun;18(6):3586-95. PMID:9584199
↑van der Vlag J, Otte AP. Transcriptional repression mediated by the human polycomb-group protein EED involves histone deacetylation. Nat Genet. 1999 Dec;23(4):474-8. PMID:10581039 doi:10.1038/70602
↑Bracken AP, Pasini D, Capra M, Prosperini E, Colli E, Helin K. EZH2 is downstream of the pRB-E2F pathway, essential for proliferation and amplified in cancer. EMBO J. 2003 Oct 15;22(20):5323-35. PMID:14532106 doi:10.1093/emboj/cdg542
↑Pasini D, Bracken AP, Jensen MR, Lazzerini Denchi E, Helin K. Suz12 is essential for mouse development and for EZH2 histone methyltransferase activity. EMBO J. 2004 Oct 13;23(20):4061-71. Epub 2004 Sep 23. PMID:15385962 doi:10.1038/sj.emboj.7600402
↑Kirmizis A, Bartley SM, Kuzmichev A, Margueron R, Reinberg D, Green R, Farnham PJ. Silencing of human polycomb target genes is associated with methylation of histone H3 Lys 27. Genes Dev. 2004 Jul 1;18(13):1592-605. PMID:15231737 doi:10.1101/gad.1200204
↑Cao R, Zhang Y. SUZ12 is required for both the histone methyltransferase activity and the silencing function of the EED-EZH2 complex. Mol Cell. 2004 Jul 2;15(1):57-67. PMID:15225548 doi:10.1016/j.molcel.2004.06.020
↑Vire E, Brenner C, Deplus R, Blanchon L, Fraga M, Didelot C, Morey L, Van Eynde A, Bernard D, Vanderwinden JM, Bollen M, Esteller M, Di Croce L, de Launoit Y, Fuks F. The Polycomb group protein EZH2 directly controls DNA methylation. Nature. 2006 Feb 16;439(7078):871-4. Epub 2005 Dec 14. PMID:16357870 doi:10.1038/nature04431
↑Sarma K, Margueron R, Ivanov A, Pirrotta V, Reinberg D. Ezh2 requires PHF1 to efficiently catalyze H3 lysine 27 trimethylation in vivo. Mol Cell Biol. 2008 Apr;28(8):2718-31. doi: 10.1128/MCB.02017-07. Epub 2008 Feb, 19. PMID:18285464 doi:10.1128/MCB.02017-07
↑Xu C, Bian C, Yang W, Galka M, Ouyang H, Chen C, Qiu W, Liu H, Jones AE, Mackenzie F, Pan P, Li SS, Wang H, Min J. Binding of different histone marks differentially regulates the activity and specificity of polycomb repressive complex 2 (PRC2). Proc Natl Acad Sci U S A. 2010 Oct 25. PMID:20974918 doi:10.1073/pnas.1008937107
↑Xu C, Bian C, Yang W, Galka M, Ouyang H, Chen C, Qiu W, Liu H, Jones AE, Mackenzie F, Pan P, Li SS, Wang H, Min J. Binding of different histone marks differentially regulates the activity and specificity of polycomb repressive complex 2 (PRC2). Proc Natl Acad Sci U S A. 2010 Oct 25. PMID:20974918 doi:10.1073/pnas.1008937107
