TY - JOUR A1 - Subasic, Deni A1 - Brümmer, Anneke A1 - Wu, Yibo A1 - Pinto, Sérgio Morgado A1 - Imig, Jochen A1 - Keller, Martin A1 - Jovanovic, Marko A1 - Lightfoot, Helen Louise A1 - Nasso, Sara A1 - Goetze, Sandra A1 - Brunner, Erich A1 - Hall, Jonathan A1 - Aebersold, Ruedi A1 - Zavolan, Mihaela A1 - Hengartner, Michael O. T1 - Cooperative target mRNA destabilization and translation inhibition by miR-58 microRNA family in C. elegans Y1 - 2015/11/01 JF - Genome Research JO - Genome Research SP - 1680 EP - 1691 DO - 10.1101/gr.183160.114 VL - 25 IS - 11 UR - http://genome.cshlp.org/content/25/11/1680.abstract N2 - In animals, microRNAs frequently form families with related sequences. The functional relevance of miRNA families and the relative contribution of family members to target repression have remained, however, largely unexplored. Here, we used the Caenorhabditis elegans miR-58 miRNA family, composed primarily of the four highly abundant members miR-58.1, miR-80, miR-81, and miR-82, as a model to investigate the redundancy of miRNA family members and their impact on target expression in an in vivo setting. We found that miR-58 family members repress largely overlapping sets of targets in a predominantly additive fashion. Progressive deletions of miR-58 family members lead to cumulative up-regulation of target protein and RNA levels. Phenotypic defects could only be observed in the family quadruple mutant, which also showed the strongest change in target protein levels. Interestingly, although the seed sequences of miR-80 and miR-58.1 differ in a single nucleotide, predicted canonical miR-80 targets were efficiently up-regulated in the mir-58.1 single mutant, indicating functional redundancy of distinct members of this miRNA family. At the aggregate level, target binding leads mainly to mRNA degradation, although we also observed some degree of translational inhibition, particularly in the single miR-58 family mutants. These results provide a framework for understanding how miRNA family members interact to regulate target mRNAs. ER -