Antisense COOLAIR mediates the coordinated switching of chromatin states at FLC during vernalization
Antisense COOLAIR mediates the coordinated switching of chromatin states at FLC during vernalization
复制标题
DOI：
10.1073/pnas.1419030111
复制
发表时间：
2014-11-11
影响因子：
11.1
通讯作者：
Dean, Caroline
中科院分区：
文献类型：
--
作者：
Csorba, Tibor;Questa, Julia I.;Dean, Caroline
已提出长期非编码RNA（LNCRNA）在基因调节中起重要作用。但是，它们在表观遗传沉默以及如何确定特异性中的重要性仍然存在争议。我们已经调查了拟南芥开花基因座C（FLC）涉及的冷诱导的表观遗传开关机制，该机制发生在春季期间。反义转录本统称为coolair，在组蛋白3赖氨酸27三甲基化（H3K27me3）的主要积聚（Polycomb沉默的特征）之前，是由长时间的寒冷诱导的。我们发现Coolair与FLC基因座物理相关，并在冷暴露期间加速了FLC的转录关闭。在寒冷期间，去除Coolair的去除破坏了H3K36甲基化与H3K27me3的同步替换，在寒冷的基因内FLC成核位点上的同步替换。一致地，遗传分析表明Coolair和Polycomb复合物在FLC的冷依赖沉默中独立起作用。我们的数据揭示了LNCRNA在表观遗传调节过程中发生的染色质状态的协调转换中的作用。
Long noncoding RNAs (lncRNAs) have been proposed to play important roles in gene regulation. However, their importance in epigenetic silencing and how specificity is determined remain controversial. We have investigated the cold-induced epigenetic switching mechanism involved in the silencing of Arabidopsis thaliana FLOWERING LOCUS C (FLC), which occurs during vernalization. Antisense transcripts, collectively named COOLAIR, are induced by prolonged cold before the major accumulation of histone 3 lysine 27 trimethylation (H3K27me3), characteristic of Polycomb silencing. We have found that COOLAIR is physically associated with the FLC locus and accelerates transcriptional shutdown of FLC during cold exposure. Removal of COOLAIR disrupted the synchronized replacement of H3K36 methylation with H3K27me3 at the intragenic FLC nucleation site during the cold. Consistently, genetic analysis showed COOLAIR and Polycomb complexes work independently in the cold-dependent silencing of FLC. Our data reveal a role for lncRNA in the coordinated switching of chromatin states that occurs during epigenetic regulation.