The Decapping Scavenger Enzyme DCS-1 Controls MicroRNA Levels in Caenorhabditis elegans

SummaryIn metazoans, microRNAs play a critical role in the posttranscriptional regulation of genes required for cell proliferation and differentiation. MicroRNAs themselves are regulated by a multitude of mechanisms influencing their transcription and posttranscriptional maturation. However, there is only sparse knowledge on pathways regulating the mature, functional form of microRNA. Here, we uncover the implication of the decapping scavenger protein DCS-1 in the control of microRNA turnover. In Caenorhabditis elegans, mutations in dcs-1 increase the levels of functional microRNAs. We demonstrate that DCS-1 interacts with the exonuclease XRN-1 to promote microRNA degradation in an independent manner from its known decapping scavenger activity, establishing two molecular functions for DCS-1. Our findings thus indicate that DCS-1 is part of a degradation complex that performs microRNA turnover in animals.

Graphical AbstractFigure optionsDownload full-size imageDownload high-quality image (168 K)Download as PowerPoint slideHighlights► The loss of the dcs-1 gene leads to an accumulation of functional miRNAs ► DCS-1 interacts with XRN-1 to promote miRNA degradation ► The role of DCS-1 in miRNA turnover is independent of its decapping scavenger activity ► DCS-1 is a constituent of a complex that is important for miRNA turnover in animals