mRNA translation is not a prerequisite for small interfering RNA-mediated mRNA cleavage

Department of Molecular Pharmacology, Stanford University School of Medicine, Stanford, CA 94305, USA.
Differentiation (Impact Factor: 3.44). 08/2005; 73(6):287-93. DOI: 10.1111/j.1432-0436.2005.00029.x
Source: PubMed


RNA interference constitutes a major means of eliminating mRNAs, yet how the small interfering RNAs (siRNA) within the RNA-induced silencing complex (RISC) finds its homologous target in the cell remains unknown. An attractive hypothesis is that RNA interference is linked to translation which allows RISC ready access to every translated mRNA. To test whether translation could direct siRNAs to mRNAs, chemical and biological inhibitors of translation and their effects on mRNA cleavage were tested. Our results show that mRNA degradation by siRNAs is not dependent on mRNA translation.

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    • "Ago-2 is considered to be localized in discrete foci, socalled P-bodies, in which programmed RNA degradation takes place (Liu et al., 2005; Sen et al., 2005). It is, however, unclear whether P-bodies just serve as a storage facility for RISC components or whether RNAi takes place in P-bodies (Rossi, 2005). "
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