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RNA editing of the microRNA-151 precursor blocks cleavage by the Dicer-TRBP complex.

ABSTRACT: MicroRNAs (miRNAs) mediate translational repression or degradation of their target messenger RNAs by RNA interference (RNAi). The primary transcripts of miRNA genes (pri-miRNAs) are sequentially processed by the nuclear Drosha-DGCR8 complex to approximately 60-70 nucleotide (nt) intermediates (pre-miRNAs) and then by the cytoplasmic Dicer-TRBP complex to approximately 20-22 nt mature miRNAs. Certain pri-miRNAs are subject to RNA editing that converts adenosine to inosine (A --> I RNA editing); however, the fate of edited pri-miRNAs is mostly unknown. Here, we provide evidence that RNA editing of pri-miR-151 results in complete blockage of its cleavage by Dicer and accumulation of edited pre-miR-151 RNAs. Our results indicate that A --> I conversion at two specific positions of the pre-miRNA foldback structure can affect its interaction with the Dicer-TRBP complex, showing a new regulatory role of A --> I RNA editing in miRNA biogenesis.

SUBMITTER: Kawahara Y

PROVIDER: S-EPMC1978079 | biostudies-other | 2007 Aug

REPOSITORIES: biostudies-other

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RNA editing of the microRNA-151 precursor blocks cleavage by the Dicer-TRBP complex.

Kawahara Yukio Y Zinshteyn Boris B Chendrimada Thimmaiah P TP Shiekhattar Ramin R Nishikura Kazuko K

EMBO reports 20070622 8

MicroRNAs (miRNAs) mediate translational repression or degradation of their target messenger RNAs by RNA interference (RNAi). The primary transcripts of miRNA genes (pri-miRNAs) are sequentially processed by the nuclear Drosha-DGCR8 complex to approximately 60-70 nucleotide (nt) intermediates (pre-miRNAs) and then by the cytoplasmic Dicer-TRBP complex to approximately 20-22 nt mature miRNAs. Certain pri-miRNAs are subject to RNA editing that converts adenosine to inosine (A --> I RNA editing); h ...[more]

PMID: 17599088

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