STV1, a ribosomal protein, binds primary microRNA transcripts to promote their interaction with the processing complex in Arabidopsis
STV1, a ribosomal protein, binds primary microRNA transcripts to promote their interaction with the processing complex in Arabidopsis
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STV1 是一种核糖体蛋白，与初级 microRNA 转录物结合，促进它们与拟南芥加工复合物的相互作用。
DOI：
10.1073/pnas.1613069114
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发表时间：
2017-02-07
影响因子：
11.1
通讯作者：
Yu, Bin
中科院分区：
文献类型：
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作者：
Li, Shengjun;Liu, Kan;Yu, Bin
MicroRNAs(MiRNAs)是基因表达的关键调控因子。它们是从初级miRNA转录本(pri-miRNAs)加工而来，其中大部分是由DNA依赖聚合酶II(POL II)转录的。MiRNA水平受到精确控制，以维持各种生物过程。在这里，我们报道了短阀1(STV1)，一种保守的核糖体蛋白，在拟南芥的miRNA生物发生中发挥作用。STV1的一部分定位于细胞核，并与pri-miRNAs结合。以原始R172b为报告基因，我们发现STV1在pri-miRNAs中通过一条短的5‘臂与茎环结合。缺乏STV1降低了pri-miRNAs与其加工复合体的联系。这些数据表明，STV1通过促进pri-miRNAs的招募来促进miRNA的生物发生。此外，我们还证明了STV1间接参与了Pol II在miRNA编码基因(MIR)启动子上的占据，并影响了MIR启动子的活性。基于这些结果，我们认为STV1通过其对pri-miRNA加工和转录的联合作用来精炼miRNAs的积累。本研究揭示了STV1的体外功能。
MicroRNAs (miRNAs) are key regulators of gene expression. They are processed from primary miRNA transcripts (pri-miRNAs), most of which are transcribed by DNA-dependent polymerase II (Pol II). miRNA levels are precisely controlled to maintain various biological processes. Here, we report that SHORT VALVE 1 (STV1), a conserved ribosomal protein, acts in miRNA biogenesis in Arabidopsis. A portion of STV1 localizes in the nucleus and binds pri-miRNAs. Using primiR172b as a reporter, we show that STV1 binds the stem-loop flanked by a short 5' arm within pri-miRNAs. Lack of STV1 reduces the association of pri-miRNAs with their processing complex. These data suggest that STV1 promotes miRNA biogenesis through facilitating the recruitment of pri-miRNAs to their processing complex. Furthermore, we show that STV1 indirectly involves in the occupancy of Pol II at the promoters of miRNA coding genes (MIR) and influences MIR promoter activities. Based on these results, we propose that STV1 refines the accumulation of miRNAs through its combined effects on pri-miRNA processing and transcription. This study uncovers an extraribosomal function of STV1.