Taguchi Y-H
Department of Physics, Chuo University, Tokyo 112-8551, Japan.
Cells. 2018 Jun 4;7(6):54. doi: 10.3390/cells7060054.
MicroRNA (miRNA) transfection is known to degrade target mRNAs and to decrease mRNA expression. In contrast to the notion that most of the gene expression alterations caused by miRNA transfection involve downregulation, they often involve both up- and downregulation; this phenomenon is thought to be, at least partially, mediated by sequence-nonspecific off-target effects. In this study, I used tensor decomposition-based unsupervised feature extraction to identify genes whose expression is likely to be altered by miRNA transfection. These gene sets turned out to largely overlap with one another regardless of the type of miRNA or cell lines used in the experiments. These gene sets also overlap with the gene set associated with altered expression induced by a Dicer knockout. This result suggests that the off-target effect is at least as important as the canonical function of miRNAs that suppress translation. The off-target effect is also suggested to consist of competition for the protein machinery between transfected miRNAs and miRNAs in the cell. Because the identified genes are enriched in various biological terms, these genes are likely to play critical roles in diverse biological processes.
已知微小RNA（miRNA）转染会降解靶mRNA并降低mRNA表达。与大多数由miRNA转染引起的基因表达改变涉及下调的观念相反，它们通常涉及上调和下调；这种现象被认为至少部分是由序列非特异性脱靶效应介导的。在本研究中，我使用基于张量分解的无监督特征提取来鉴定其表达可能因miRNA转染而改变的基因。无论实验中使用的miRNA类型或细胞系如何，这些基因集结果显示在很大程度上相互重叠。这些基因集也与由Dicer敲除诱导的表达改变相关的基因集重叠。这一结果表明脱靶效应至少与miRNA抑制翻译的经典功能一样重要。脱靶效应还被认为包括转染的miRNA与细胞内miRNA之间对蛋白质机制的竞争。由于鉴定出的基因在各种生物学术语中富集，这些基因可能在多种生物学过程中发挥关键作用。
