Department Epigenetics and Cancer FRE 3377, Centre National de la Recherche Scientifique, Commissariat à l'Energie Atomique Saclay, Gif-sur-Yvette, France ; Université Paris-Sud, Gif-sur-Yvette, France.
PLoS One. 2013 Aug 21;8(8):e71927. doi: 10.1371/journal.pone.0071927. eCollection 2013.
MiRNAs impact on the control of cell fate by regulating gene expression at the post-transcriptional level. Here, using mammalian muscle differentiation as a model and a phenotypic loss-of-function screen, we explored the function of miRNAs at the genome-wide level. We found that the depletion of a high number of miRNAs (63) impacted on differentiation of human muscle precursors, underscoring the importance of this post-transcriptional mechanism of gene regulation. Interestingly, a comparison with miRNA expression profiles revealed that most of the hit miRNAs did not show any significant variations of expression during differentiation. These constitutively expressed miRNAs might be required for basic and/or essential cell function, or else might be regulated at the post-transcriptional level. MiRNA inhibition yielded a variety of phenotypes, reflecting the widespread miRNA involvement in differentiation. Using a functional screen (the STarS--Suppressor Target Screen--approach, i. e. concomitant knockdown of miRNAs and of candidate target proteins), we discovered miRNA protein targets that are previously uncharacterized controllers of muscle-cell terminal differentiation. Our results provide a strategy for functional annotation of the human miRnome.
miRNAs 通过在转录后水平调控基因表达来影响细胞命运的控制。在这里，我们使用哺乳动物肌肉分化作为模型，并进行表型功能丧失筛选，在全基因组水平上探索 miRNAs 的功能。我们发现，大量 miRNAs（63 种）的耗竭会影响人类肌肉前体细胞的分化，这突显了这种基因调控的转录后机制的重要性。有趣的是，与 miRNA 表达谱的比较表明，大多数命中的 miRNAs 在分化过程中没有表现出任何显著的表达变化。这些组成性表达的 miRNA 可能是基本的和/或必需的细胞功能所必需的，或者可能在转录后水平受到调控。miRNA 抑制产生了多种表型，反映了 miRNA 广泛参与分化。我们使用功能筛选（STarS——抑制靶标筛选方法，即同时敲低 miRNAs 和候选靶蛋白），发现了以前未被表征的 miRNA 蛋白靶标，它们是肌肉细胞终末分化的控制器。我们的结果为人类 miRnome 的功能注释提供了一种策略。
