60
views
0
recommends
+1 Recommend
0 collections
    4
    shares
      • Record: found
      • Abstract: found
      • Article: not found

      Decay of mRNAs targeted by RISC requires XRN1, the Ski complex, and the exosome.

      RNA (New York, N.Y.)
      Acyltransferases, genetics, metabolism, Animals, Cell Line, Drosophila Proteins, Drosophila melanogaster, Exoribonucleases, Nuclear Proteins, RNA Interference, RNA Stability, RNA, Messenger, RNA-Induced Silencing Complex, Saccharomyces cerevisiae Proteins

      Read this article at

      ScienceOpenPublisherPMC
      Bookmark
          There is no author summary for this article yet. Authors can add summaries to their articles on ScienceOpen to make them more accessible to a non-specialist audience.

          Abstract

          RNA interference (RNAi) is a conserved RNA silencing pathway that leads to sequence-specific mRNA decay in response to the presence of double-stranded RNA (dsRNA). Long dsRNA molecules are first processed by Dicer into 21-22-nucleotide small interfering RNAs (siRNAs). The siRNAs are incorporated into a multimeric RNA-induced silencing complex (RISC) that cleaves mRNAs at a site determined by complementarity with the siRNAs. Following this initial endonucleolytic cleavage, the mRNA is degraded by a mechanism that is not completely understood. We investigated the decay pathway of mRNAs targeted by RISC in Drosophila cells. We show that 5' mRNA fragments generated by RISC cleavage are rapidly degraded from their 3' ends by the exosome, whereas the 3' fragments are degraded from their 5' ends by XRN1. Exosome-mediated decay of the 5' fragments requires the Drosophila homologs of yeast Ski2p, Ski3p, and Ski8p, suggesting that their role as regulators of exosome activity is conserved. Our findings indicate that mRNAs targeted by siRNAs are degraded from the ends generated by RISC cleavage, without undergoing decapping or deadenylation.

          Related collections

          Author and article information

          Comments

          Comment on this article