The exonuclease ERI-1 has a conserved dual role in 5.8S rRNA processing and RNAi

Department of Genetics, Harvard Medical School, and Department of Molecular Biology, Massachusetts General Hospital, CPZN7250, 185 Cambridge Street, Boston, Massachusetts 02114, USA.
Nature Structural & Molecular Biology (Impact Factor: 13.31). 06/2008; 15(5):531-3. DOI: 10.1038/nsmb.1411
Source: PubMed


The exonuclease ERI-1 negatively regulates RNA interference in Caenorhabditis elegans and Schizosaccharomyces pombe, and is required for production of some C. elegans endogenous small interfering RNAs. We show that ERI-1 performs 3' end processing of the 5.8S ribosomal RNA in both C. elegans and S. pombe. In C. elegans, two protein isoforms of ERI-1 are localized to the cytoplasm, and each has distinct functions in ribosomal RNA processing and negative regulation of RNA interference.

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Available from: Harrison W Gabel
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    • "We used unc-73 gene to produce uncoordinated phenotype. Silencing of unc-73 is already known for its post embryonic uncoordinated phenotypes in number of studies [8], [15], [17]–[19]. In C. elegans, unc-73 (F55C7.7) is predicted to encode a guanine nucleotide exchange factor (GEF), a regulator of Rac GTPase which is expressed in neurons, muscles and in the gonad [20], [21] and plays an important role in axon guidance [22]. "
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    • "Exonuclease Eri-1 (enhanced RNAi) has been reported to have negative regulatory effects on RNAi (Gabel and Ruvkun , 2008). Eri-1 can degrade the 3¢ end of siRNA and histone mRNA in Caenorhabditis elegans, humans, and fission yeast (Hong et al., 2005; Gabel and Ruvkun, 2008). Administration of high doses of siRNA induces Eri-1 expression in mice (Hong et al., 2005). "
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    • "The other category comprises gene homologues of ERI1. Apart from its role in the destruction of siRNA, ERI1 is also involved in 5.8S ribosomal RNA processing (Ansel et al., 2008; Gabel and Ruvkun, 2008). The absence of this protein may explain in part why silencing may persist almost indefinitely in some Phytophthora species in the absence of the primary silencing signal (Gaulin et al., 2007; van West et al., 1999). "
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