文章作者为清华大学戚益军教授。AGO蛋白被公认为可以结合与small RNA，并指导转录后基因的沉默。本文发现，在外界环境刺激条件下（比如激素，逆境），拟南芥AGO1可以结合于染色质并促进基因的转录。AGO1的这种结合作用需要small RNA 和SWI/SNF 染色质重塑复合物的参与。

Arabidopsis ARGONAUTE 1 Binds Chromatin to Promote Gene Transcription in Response to Hormones and Stresses

常规RNA干扰（RNAi）途径在转录或转录后水平抑制真核基因表达。 RNAi 的核心是small RNAs (sRNAs)和效应子AGO 蛋白。已知拟南芥AGO1结合于miRNAs，并在转录后抑制细胞质中的靶基因表达。我们报道AGO1还结合于活性基因的染色质，并促进其转录。结果显示，sRNA和SWI/SNF复合物与核AGO1相关联，并且是AGO1与染色质结合所必需的。此外，我们还表明，各种刺激（包括植物激素和逆境），可以特异的触发AGO1结合到刺激响应基因。最后，我们表明AGO1促进茉莉酸（JA）信号通路中的基因的诱导和JA反应的激活。我们的研究结果表明，通过结合和促进刺激特定基因的表达，AGO1可能参与调节多种信号通路和相关的生物学过程。

Conventional RNA interference (RNAi) pathways suppress eukaryotic gene expression at the transcriptional or post-transcriptional level. At the core of RNAi are small RNAs (sRNAs) and effector Argonaute (AGO) proteins. Arabidopsis AGO1 is known to bind microRNAs (miRNAs) and post-transcriptionally repress target genes in the cytoplasm. Here, we report that AGO1 also binds to the chromatin of active genes and promotes their transcription. We show that sRNAs and SWI/SNF complexes associate with nuclear AGO1 and are required for AGO1 binding to chromatin. Moreover, we show that various stimuli, including plant hormones and stresses, specifically trigger AGO1 binding to stimulus-responsive genes. Finally, we show that AGO1 facilitates the induction of genes in jasmonate (JA) signaling pathways and the activation of JA responses. Our findings suggest that, by binding and facilitating the expression of stimuli-specific genes, AGO1 may regulate diverse signaling pathways and associated biological processes.

每日一词

conventional

英[kənˈvenʃənl]

美[kənˈvɛnʃənəl]

adj. 传统的; 习用的，平常的; 依照惯例的; 约定的;

[例句]It is simpler and quicker to use than conventional methods.

这比通常的做法更简单、更快捷。