Long non-coding RNA produced by RNA polymerase V determines boundaries of heterochromatin
Long non-coding RNA produced by RNA polymerase V determines boundaries of heterochromatin
复制标题
DOI：
10.7554/elife.19092
复制
发表时间：
2016-10-25
期刊：
影响因子：
7.7
通讯作者：
Wierzbicki, Andrzej T.
中科院分区：
文献类型：
--
作者：
Bohmdorfer, Gudrun;Sethuraman, Shriya;Wierzbicki, Andrzej T.
rna介导的转录基因沉默是一个保守的过程，其中小rna通过建立染色质修饰靶向转座子和其他序列进行抑制。这一过程的核心要素是长链非编码RNA (lncRNA)，在拟南芥中，它是由一种称为Pol V的特殊RNA聚合酶产生的。在这里，我们发现Pol V的非编码转录是由位于转录区域内的预先存在的染色质修饰控制的。大多数Pol V转录本与AGO4相关，但不被AGO4切割。Pol - v依赖性DNA甲基化建立在DNA的两条链上，并严格限制于Pol - v转录区域。这表明染色质修饰是在靠近Pol V的地方建立的。最后，Pol V转录优先富集在沉默转座元件的边缘，在那里Pol V转录成TEs。我们认为Pol V可能在异染色质边界的确定中起重要作用。
RNA-mediated transcriptional gene silencing is a conserved process where small RNAs target transposons and other sequences for repression by establishing chromatin modifications. A central element of this process are long non-coding RNAs (lncRNA), which in Arabidopsis thaliana are produced by a specialized RNA polymerase known as Pol V. Here we show that non-coding transcription by Pol V is controlled by preexisting chromatin modifications located within the transcribed regions. Most Pol V transcripts are associated with AGO4 but are not sliced by AGO4. Pol V-dependent DNA methylation is established on both strands of DNA and is tightly restricted to Pol V-transcribed regions. This indicates that chromatin modifications are established in close proximity to Pol V. Finally, Pol V transcription is preferentially enriched on edges of silenced transposable elements, where Pol V transcribes into TEs. We propose that Pol V may play an important role in the determination of heterochromatin boundaries.