6jnl
From Proteopedia
REF6 ZnF2-4-NAC004 complex
Structural highlights
FunctionREF6_ARATH Histone demethylase that demethylates 'Lys-27' (H3K27me) of histone H3. Demethylates both tri- (H3K27me3) and di-methylated (H3K27me2) H3K27me (PubMed:21642989, PubMed:27111035). Demethylates also H3K4me3/2 and H3K36me3/2 in an in vitro assay (PubMed:20711170). Involved in the transcriptional regulation of hundreds of genes regulating developmental patterning and responses to various stimuli (PubMed:18467490). Binds DNA via its four zinc fingers in a sequence-specific manner, 5'-CTCTGYTY-3', to promote the demethylation of H3K27me3 and the regulation of organ boundary formation (PubMed:27111034, PubMed:27111035). Involved in the regulation of flowering time by repressing FLOWERING LOCUS C (FLC) expression (PubMed:15377760). Interacts with the NF-Y complexe to regulate SOC1 (PubMed:25105952). Mediates the recruitment of BRM to its target loci (PubMed:27111034).[1] [2] [3] [4] [5] [6] [7] Publication Abstract from PubMedRELATIVE OF EARLY FLOWERING 6 (REF6/JMJ12), a Jumonji C (JmjC)-domain-containing H3K27me3 histone demethylase, finds its target loci in Arabidopsis genome by directly recognizing the CTCTGYTY motif via its zinc-finger (ZnF) domains. REF6 tends to bind motifs located in active chromatin states that are depleted for heterochromatic modifications. However, the underlying mechanism remains unknown. Here, we show that REF6 preferentially bind to hypo-methylated CTCTGYTY motifs in vivo, and that CHG methylation decreases REF6 DNA binding affinity in vitro. In addition, crystal structures of ZnF-clusters in complex with DNA oligonucleotides reveal that 5-methylcytosine is unfavorable for REF6 binding. In drm1 drm2 cmt2 cmt3 (ddcc) quadruple mutants, in which non-CG methylation is significantly reduced, REF6 can ectopically bind a small number of new target loci, most of which are located in or neighbored with short TEs in euchromatic regions. Collectively, our findings reveal that DNA methylation, likely acting in combination with other epigenetic modifications, may partially explain why REF6 binding is depleted in heterochromatic loci. DNA methylation repels targeting of Arabidopsis REF6.,Qiu Q, Mei H, Deng X, He K, Wu B, Yao Q, Zhang J, Lu F, Ma J, Cao X Nat Commun. 2019 May 2;10(1):2063. doi: 10.1038/s41467-019-10026-1. PMID:31048693[8] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences
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