Architecture et Réactivité de l'ARN, RNA Architecture and Reactivity, Université de Strasbourg, Centre National de la Recherche Scientifique, Institut de Biologie Moléculaire et Cellulaire, 15 rue René Descartes, 67084 Strasbourg Cedex, France.
Proc Natl Acad Sci U S A. 2011 Oct 4;108(40):E794-802. doi: 10.1073/pnas.1103698108. Epub 2011 Sep 6.
Several classes of small noncoding RNAs are key players in cellular metabolism including mRNA decoding, RNA processing, and mRNA stability. Here we show that a tRNA(Asp) isodecoder, corresponding to a human tRNA-derived sequence, binds to an embedded Alu RNA element contained in the 3' UTR of the human aspartyl-tRNA synthetase mRNA. This interaction between two well-known classes of RNA molecules, tRNA and Alu RNA, is driven by an unexpected structural motif and induces a global rearrangement of the 3' UTR. Besides, this 3' UTR contains two functional polyadenylation signals. We propose a model where the tRNA/Alu interaction would modulate the accessibility of the two alternative polyadenylation sites and regulate the stability of the mRNA. This unique regulation mechanism would link gene expression to RNA polymerase III transcription and may have implications in a primate-specific signal pathway.
几类小分子非编码 RNA 是细胞代谢的关键参与者，包括 mRNA 解码、RNA 处理和 mRNA 稳定性。在这里，我们发现一种对应的 tRNA（Asp）脱氨酶，它与人类 tRNA 衍生序列相对应，可与天冬氨酰-tRNA 合成酶 mRNA 3'UTR 中包含的内含 Alu RNA 元件结合。这种两种已知 RNA 分子（tRNA 和 Alu RNA）之间的相互作用由一个意想不到的结构模体驱动，并诱导 3'UTR 的整体重排。此外，该 3'UTR 包含两个功能多聚腺苷酸化信号。我们提出了一个模型，其中 tRNA/Alu 相互作用可以调节两个替代多聚腺苷酸化位点的可及性，并调节 mRNA 的稳定性。这种独特的调节机制将基因表达与 RNA 聚合酶 III 转录联系起来，可能在灵长类动物特有的信号通路中具有重要意义。
