Dicer-2 promotes mRNA activation through cytoplasmic polyadenylation

Olga Coll (1) , Tanit Guitart (1, 2) , Ana Villalba (1) , Catherine Papin (3) , Martine Simonelig (3) , Fátima Gebauer (1, 2)

1 CRG - Centre for Genomic Regulation - Centre de Regulació Genòmica [Barcelona]
2 UPF - Universitat Pompeu Fabra [Barcelona]
3 IGH - Institut de génétique humaine

Cytoplasmic polyadenylation is a widespread mechanism to regulate mRNA translation. In vertebrates, this process requires two sequence elements in target 3' UTRs: the U-rich cytoplasmic polyadenylation element and the AAUAAA hexanucleotide. InDrosophila melanogaster, cytoplasmic polyadenylation ofTollmRNA occurs independently of these canonical elements and requires a machinery that remains to be characterized. Here we identify Dicer-2 as a component of this machinery. Dicer-2, a factor previously involved in RNA interference (RNAi), interacts with the cytoplasmic poly(A) polymerase Wispy. Depletion of Dicer-2 from polyadenylation-competent embryo extracts and analysis ofwispymutants indicate that both factors are necessary for polyadenylation and translation ofTollmRNA. We further identifyr2d2mRNA, encoding a Dicer-2 partner in RNAi, as a Dicer-2 polyadenylation target. Our results uncover a novel function of Dicer-2 in activation of mRNA translation through cytoplasmic polyadenylation.

Mots clés: Dicer-2; Wispy; cytoplasmic polyadenylation; translation

Domaines: Sciences du Vivant [q-bio]; Génétique

Olga Coll, Tanit Guitart, Ana Villalba, Catherine Papin, Martine Simonelig, et al.. Dicer-2 promotes mRNA activation through cytoplasmic polyadenylation. RNA, 2018, 24 (4), pp.529 - 539. ⟨10.1261/rna.065417.117⟩. ⟨hal-01741800⟩