RNAi in budding yeast

Whitehead Institute for Biomedical Research, 9 Cambridge Center, Cambridge, MA 02142, USA.
Science (Impact Factor: 33.61). 10/2009; 326(5952):544-50. DOI: 10.1126/science.1176945
Source: PubMed


RNA interference (RNAi), a gene-silencing pathway triggered by double-stranded RNA, is conserved in diverse eukaryotic species but has been lost in the model budding yeast Saccharomyces cerevisiae. Here, we show that RNAi is present in other budding yeast species, including Saccharomyces castellii and Candida albicans. These species use noncanonical Dicer proteins to generate small interfering RNAs, which mostly correspond to transposable elements and Y' subtelomeric repeats. In S. castellii, RNAi mutants are viable but have excess Y' messenger RNA levels. In S. cerevisiae, introducing Dicer and Argonaute of S. castellii restores RNAi, and the reconstituted pathway silences endogenous retrotransposons. These results identify a previously unknown class of Dicer proteins, bring the tool of RNAi to the study of budding yeasts, and bring the tools of budding yeast to the study of RNAi.

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Available from: Gerald Fink, Apr 24, 2014
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    • "RNAi, a gene-silencing pathway triggered by double-stranded RNA, has been lost in the model budding yeast S. cerevisiae, but the introduction of Dicer (Dcr1) and Argonaute (Ago1) from Saccharomyces castellii leads to the production of artificial siRNAs. RNAi-competent S. cerevisae thus allows the identification of small RNAs (19–23 nts), corresponding to naturally formed RNA duplexes in vivo (Drinnenberg et al., 2009; see Experimental Procedures). We therefore used this RNAi tool to determine the density of small RNAs produced in the presence or absence of Dcr1/Ago1 in both wild-type and xrn1 mutant strains. "
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    Cell Reports 09/2015; 12(11). DOI:10.1016/j.celrep.2015.08.016 · 8.36 Impact Factor
    • "The loss of RNAi in the budding yeast, Saccharomyces cerevisiae (phylum Ascomycota), is believed to result from adaptation to the presence of Saccharomyces cerevisiae L-A virus. This virus and its satellite-encoded 'killer' toxins provide a selective advantage for the host in competition against yeast strains lacking immunity to the toxin (Drinnenberg et al., 2009, 2011). "
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