Sorting of small RNAs into Arabidopsis argonaute complexes is directed by the 5′ terminal nucleotide
Sorting of small RNAs into Arabidopsis argonaute complexes is directed by the 5′ terminal nucleotide
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DOI：
10.1016/j.cell.2008.02.034
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发表时间：
2008-04-04
期刊：
影响因子：
64.5
通讯作者：
Qi, Yijun
中科院分区：
文献类型：
--
作者：
Mi, Shijun;Cai, Tao;Qi, Yijun
Argonaute（AGO）蛋白招募小RNA形成RNAi效应复合物的核心。拟南芥编码10个AGO蛋白和一个大的小RNA网络。这些小RNA如何被分选成特定的AGO复合物在很大程度上仍然未知。我们已经编目小RNA驻留在四个AGO复合物。我们发现AGO2和AGO4优先招募5 '末端带有腺苷的小RNA，而AGO1则携带有利于5 '末端尿苷的microRNA（miRNAs）。AGO5主要结合以胞嘧啶起始的小RNA。改变miRNA的5 '末端核苷酸可预见地将其重定向到不同的AGO复合物中并改变其生物活性。这些结果揭示了小RNA序列在AGO复合物中的作用。这表明AGO复合物的特化可能涉及重塑5 '端结合口袋以接受某些小RNA序列，这可能解释了miRNA以尿苷起始的进化驱动。
Argonaute (AGO) proteins recruit small RNAs to form the core of RNAi effector complexes. Arabidopsis encodes ten AGO proteins and a large network of small RNAs. How these small RNAs are sorted into specific AGO complexes remains largely unknown. We have cataloged small RNAs resident in four AGO complexes. We found that AGO2 and AGO4 preferentially recruit small RNAs with a 5 ' terminal adenosine, whereas AGO1 harbors microRNAs (miRNAs) that favor a 5 ' terminal uridine. AGO5 predominantly binds small RNAs that initiate with cytosine. Changing the 5 ' terminal nucleotide of an miRNA predictably redirected it into a different AGO complex and alters its biological activity. These results reveal a role for small RNA sequences in assorting among AGO complexes. This suggests that specialization of AGO complexes might involve remodeling the 5 ' end-binding pocket to accept certain small RNA sequences, perhaps explaining the evolutionary drive for miRNAs to initiate with uridine.