Department for Plant Cell and Molecular Biology, Institute for Biology, Humboldt-Universität zu Berlin, Berlin, Germany.
LPCV, CNRS, CEA, INRA, Université Grenoble Alpes, Grenoble, France.
Nat Plants. 2018 Sep;4(9):681-689. doi: 10.1038/s41477-018-0219-5. Epub 2018 Aug 13.
Targeted changes in chromatin state at thousands of genes are central to eukaryotic development. RELATIVE OF EARLY FLOWERING 6 (REF6) is a Jumonji-type histone demethylase that counteracts Polycomb repressive complex 2 (PRC2)-mediated gene silencing in plants and was reported to select its binding sites in a direct, sequence-specific manner. Here we show that REF6 and its two close paralogues determine spatial 'boundaries' of the repressive histone H3K27me3 mark in the genome and control the tissue-specific release from PRC2-mediated gene repression. Targeted mutagenesis revealed that these histone demethylases display pleiotropic, redundant functions in plant development, several of which depend on trans factor-mediated recruitment. Thus, Jumonji-type histone demethylases restrict repressive chromatin domains and contribute to tissue-specific gene activation via complementary targeting mechanisms.
染色质状态的靶向改变是真核生物发育的核心。早期开花 6 相关蛋白（REF6）是一种组蛋白去甲基酶，可拮抗植物中多梳抑制复合物 2（PRC2）介导的基因沉默，并被报道以直接、序列特异性的方式选择其结合位点。在这里，我们表明 REF6 及其两个密切的同源物决定了基因组中抑制性组蛋白 H3K27me3 标记的空间“边界”，并控制组织特异性从 PRC2 介导的基因抑制中释放。靶向诱变表明，这些组蛋白去甲基酶在植物发育中表现出多效性、冗余的功能，其中一些功能依赖于转录因子介导的招募。因此，组蛋白去甲基酶限制抑制性染色质结构域，并通过互补的靶向机制促进组织特异性基因激活。
