A complex system of small RNAs in the unicellular green alga Chlamydomonas reinhardtii
A complex system of small RNAs in the unicellular green alga Chlamydomonas reinhardtii
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DOI：
10.1101/gad.1543507
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发表时间：
2007-05-15
影响因子：
10.5
通讯作者：
Qi, Yijun
中科院分区：
文献类型：
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作者：
Zhao, Tao;Li, Guanglin;Qi, Yijun
内源性小RNA在RNA干扰（RNAi）途径中起作用，通过mRNA切割、翻译抑制或染色质修饰来控制基因表达。植物和动物含有许多在发育中起重要作用的microRNA（miRNAs），包括帮助指定细胞类型和组织身份。迄今为止，在单细胞生物中还没有报道过miRNA。在这里，我们表明，衣原体reinhardtii，单细胞绿色的，编码许多miRNA。我们还表明，衣原体miRNA可以在体内和体外指导其靶mRNA的切割。我们进一步表明，在衣原体配子发生过程中，一些miRNA/候选者的表达增加或减少。除了miRNA，衣原体还含有其他类型的小RNA，包括相控小干扰RNA（siRNA），其使人联想到植物反式作用siRNA，以及源自蛋白质编码基因和转座子的siRNA。我们的研究结果表明，miRNA途径和一些siRNA途径是在多细胞生物出现之前进化的古老的基因调控机制。
Endogenous small RNAs function in RNA interference (RNAi) pathways to control gene expression through mRNA cleavage, translational repression, or chromatin modification. Plants and animals contain many microRNAs (miRNAs) that play vital roles in development, including helping to specify cell type and tissue identity. To date, no miRNAs have been reported in unicellular organisms. Here we show that Chlamydomonas reinhardtii, a unicellular green alga, encodes many miRNAs. We also show that a Chlamydomonas miRNA can direct the cleavage of its target mRNA in vivo and in vitro. We further show that the expression of some miRNAs/Candidates increases or decreases during Chlamydomonas gametogenesis. In addition to miRNAs, Chlamydomonas harbors other types of small RNAs including phased small interfering RNAs (siRNAs) that are reminiscent of plant trans-acting siRNAs, as well as siRNAs originating from protein-coding genes and transposons. Our findings suggest that the miRNA pathway and some siRNA pathways are ancient mechanisms of gene regulation that evolved prior to the emergence of multicellularity.