| Structural highlights
Function
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]
Publication Abstract from PubMed
Polycomb repressive complex 2 (PRC2) silences genes through trimethylation of histone H3K27. PRC2 associates with numerous precursor messenger RNAs (pre-mRNAs) and long noncoding RNAs (lncRNAs) with a binding preference for G-quadruplex RNA. In this work, we present a 3.3-A-resolution cryo-electron microscopy structure of PRC2 bound to a G-quadruplex RNA. Notably, RNA mediates the dimerization of PRC2 by binding both protomers and inducing a protein interface composed of two copies of the catalytic subunit EZH2, thereby blocking nucleosome DNA interaction and histone H3 tail accessibility. Furthermore, an RNA-binding loop of EZH2 facilitates the handoff between RNA and DNA, another activity implicated in PRC2 regulation by RNA. We identified a gain-of-function mutation in this loop that activates PRC2 in zebrafish. Our results reveal mechanisms for RNA-mediated regulation of a chromatin-modifying enzyme.
Structural basis for inactivation of PRC2 by G-quadruplex RNA.,Song J, Gooding AR, Hemphill WO, Love BD, Robertson A, Yao L, Zon LI, North TE, Kasinath V, Cech TR Science. 2023 Sep 22;381(6664):1331-1337. doi: 10.1126/science.adh0059. Epub 2023 , Sep 21. PMID:37733873[10]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
See Also
References
- ↑ 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
- ↑ Song J, Gooding AR, Hemphill WO, Love BD, Robertson A, Yao L, Zon LI, North TE, Kasinath V, Cech TR. Structural basis for inactivation of PRC2 by G-quadruplex RNA. Science. 2023 Sep 22;381(6664):1331-1337. PMID:37733873 doi:10.1126/science.adh0059
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