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. 2001 Oct;7(10):1397–1402.

Distinct roles for RDE-1 and RDE-4 during RNA interference in Caenorhabditis elegans.

S Parrish 1, A Fire 1
PMCID: PMC1370183  PMID: 11680844

Abstract

RNA interference (RNAi) is a cellular defense mechanism that uses double-stranded RNA (dsRNA) as a sequence-specific trigger to guide the degradation of homologous single-stranded RNAs. RNAi is a multistep process involving several proteins and at least one type of RNA intermediate, a population of small 21-25 nt RNAs (called siRNAs) that are initially derived from cleavage of the dsRNA trigger. Genetic screens in Caenorhabditis elegans have identified numerous mutations that cause partial or complete loss of RNAi. In this work, we analyzed cleavage of injected dsRNA to produce the initial siRNA population in animals mutant for rde-1 and rde-4, two genes that are essential for RNAi but that are not required for organismal viability or fertility. Our results suggest distinct roles for RDE-1 and RDE-4 in the interference process. Although null mutants lacking rde-1 show no phenotypic response to dsRNA, the amount of siRNAs generated from an injected dsRNA trigger was comparable to that of wild-type. By contrast, mutations in rde-4 substantially reduced the population of siRNAs derived from an injected dsRNA trigger. Injection of chemically synthesized 24- or 25-nt siRNAs could circumvent RNAi resistance in rde-4 mutants, whereas no bypass was observed in rde-1 mutants. These results support a model in which RDE-4 is involved before or during production of siRNAs, whereas RDE-1 acts after the siRNAs have been formed.

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Selected References

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  1. Baulcombe D. C. RNA as a target and an initiator of post-transcriptional gene silencing in transgenic plants. Plant Mol Biol. 1996 Oct;32(1-2):79–88. doi: 10.1007/BF00039378. [DOI] [PubMed] [Google Scholar]
  2. Baulcombe D. Viruses and gene silencing in plants. Arch Virol Suppl. 1999;15:189–201. doi: 10.1007/978-3-7091-6425-9_14. [DOI] [PubMed] [Google Scholar]
  3. Bernstein E., Caudy A. A., Hammond S. M., Hannon G. J. Role for a bidentate ribonuclease in the initiation step of RNA interference. Nature. 2001 Jan 18;409(6818):363–366. doi: 10.1038/35053110. [DOI] [PubMed] [Google Scholar]
  4. Bosher J. M., Labouesse M. RNA interference: genetic wand and genetic watchdog. Nat Cell Biol. 2000 Feb;2(2):E31–E36. doi: 10.1038/35000102. [DOI] [PubMed] [Google Scholar]
  5. Brenner S. The genetics of Caenorhabditis elegans. Genetics. 1974 May;77(1):71–94. doi: 10.1093/genetics/77.1.71. [DOI] [PMC free article] [PubMed] [Google Scholar]
  6. Caplen N. J., Parrish S., Imani F., Fire A., Morgan R. A. Specific inhibition of gene expression by small double-stranded RNAs in invertebrate and vertebrate systems. Proc Natl Acad Sci U S A. 2001 Jul 31;98(17):9742–9747. doi: 10.1073/pnas.171251798. [DOI] [PMC free article] [PubMed] [Google Scholar]
  7. Catalanotto C., Azzalin G., Macino G., Cogoni C. Gene silencing in worms and fungi. Nature. 2000 Mar 16;404(6775):245–245. doi: 10.1038/35005169. [DOI] [PubMed] [Google Scholar]
  8. Cogoni C., Macino G. Isolation of quelling-defective (qde) mutants impaired in posttranscriptional transgene-induced gene silencing in Neurospora crassa. Proc Natl Acad Sci U S A. 1997 Sep 16;94(19):10233–10238. doi: 10.1073/pnas.94.19.10233. [DOI] [PMC free article] [PubMed] [Google Scholar]
  9. Cogoni C., Macino G. Post-transcriptional gene silencing across kingdoms. Curr Opin Genet Dev. 2000 Dec;10(6):638–643. doi: 10.1016/s0959-437x(00)00134-9. [DOI] [PubMed] [Google Scholar]
  10. Cox D. N., Chao A., Baker J., Chang L., Qiao D., Lin H. A novel class of evolutionarily conserved genes defined by piwi are essential for stem cell self-renewal. Genes Dev. 1998 Dec 1;12(23):3715–3727. doi: 10.1101/gad.12.23.3715. [DOI] [PMC free article] [PubMed] [Google Scholar]
  11. Dernburg A. F., Zalevsky J., Colaiácovo M. P., Villeneuve A. M. Transgene-mediated cosuppression in the C. elegans germ line. Genes Dev. 2000 Jul 1;14(13):1578–1583. [PMC free article] [PubMed] [Google Scholar]
  12. Edgar R. S., Wood W. B. Morphogenesis of bacteriophage T4 in extracts of mutant-infected cells. Proc Natl Acad Sci U S A. 1966 Mar;55(3):498–505. doi: 10.1073/pnas.55.3.498. [DOI] [PMC free article] [PubMed] [Google Scholar]
  13. Elbashir S. M., Harborth J., Lendeckel W., Yalcin A., Weber K., Tuschl T. Duplexes of 21-nucleotide RNAs mediate RNA interference in cultured mammalian cells. Nature. 2001 May 24;411(6836):494–498. doi: 10.1038/35078107. [DOI] [PubMed] [Google Scholar]
  14. Elbashir S. M., Lendeckel W., Tuschl T. RNA interference is mediated by 21- and 22-nucleotide RNAs. Genes Dev. 2001 Jan 15;15(2):188–200. doi: 10.1101/gad.862301. [DOI] [PMC free article] [PubMed] [Google Scholar]
  15. Elmayan T., Balzergue S., Béon F., Bourdon V., Daubremet J., Guénet Y., Mourrain P., Palauqui J. C., Vernhettes S., Vialle T. Arabidopsis mutants impaired in cosuppression. Plant Cell. 1998 Oct;10(10):1747–1758. doi: 10.1105/tpc.10.10.1747. [DOI] [PMC free article] [PubMed] [Google Scholar]
  16. Fagard M., Boutet S., Morel J. B., Bellini C., Vaucheret H. AGO1, QDE-2, and RDE-1 are related proteins required for post-transcriptional gene silencing in plants, quelling in fungi, and RNA interference in animals. Proc Natl Acad Sci U S A. 2000 Oct 10;97(21):11650–11654. doi: 10.1073/pnas.200217597. [DOI] [PMC free article] [PubMed] [Google Scholar]
  17. Fire A., Xu S., Montgomery M. K., Kostas S. A., Driver S. E., Mello C. C. Potent and specific genetic interference by double-stranded RNA in Caenorhabditis elegans. Nature. 1998 Feb 19;391(6669):806–811. doi: 10.1038/35888. [DOI] [PubMed] [Google Scholar]
  18. Grishok A., Pasquinelli A. E., Conte D., Li N., Parrish S., Ha I., Baillie D. L., Fire A., Ruvkun G., Mello C. C. Genes and mechanisms related to RNA interference regulate expression of the small temporal RNAs that control C. elegans developmental timing. Cell. 2001 Jul 13;106(1):23–34. doi: 10.1016/s0092-8674(01)00431-7. [DOI] [PubMed] [Google Scholar]
  19. Hamilton A. J., Baulcombe D. C. A species of small antisense RNA in posttranscriptional gene silencing in plants. Science. 1999 Oct 29;286(5441):950–952. doi: 10.1126/science.286.5441.950. [DOI] [PubMed] [Google Scholar]
  20. Hammond S. M., Bernstein E., Beach D., Hannon G. J. An RNA-directed nuclease mediates post-transcriptional gene silencing in Drosophila cells. Nature. 2000 Mar 16;404(6775):293–296. doi: 10.1038/35005107. [DOI] [PubMed] [Google Scholar]
  21. Ketting R. F., Haverkamp T. H., van Luenen H. G., Plasterk R. H. Mut-7 of C. elegans, required for transposon silencing and RNA interference, is a homolog of Werner syndrome helicase and RNaseD. Cell. 1999 Oct 15;99(2):133–141. doi: 10.1016/s0092-8674(00)81645-1. [DOI] [PubMed] [Google Scholar]
  22. Ketting R. F., Plasterk R. H. A genetic link between co-suppression and RNA interference in C. elegans. Nature. 2000 Mar 16;404(6775):296–298. doi: 10.1038/35005113. [DOI] [PubMed] [Google Scholar]
  23. Parrish S., Fleenor J., Xu S., Mello C., Fire A. Functional anatomy of a dsRNA trigger: differential requirement for the two trigger strands in RNA interference. Mol Cell. 2000 Nov;6(5):1077–1087. doi: 10.1016/s1097-2765(00)00106-4. [DOI] [PubMed] [Google Scholar]
  24. Sharp P. A. RNA interference--2001. Genes Dev. 2001 Mar 1;15(5):485–490. doi: 10.1101/gad.880001. [DOI] [PubMed] [Google Scholar]
  25. Smardon A., Spoerke J. M., Stacey S. C., Klein M. E., Mackin N., Maine E. M. EGO-1 is related to RNA-directed RNA polymerase and functions in germ-line development and RNA interference in C. elegans. Curr Biol. 2000 Feb 24;10(4):169–178. doi: 10.1016/s0960-9822(00)00323-7. [DOI] [PubMed] [Google Scholar]
  26. Tabara H., Sarkissian M., Kelly W. G., Fleenor J., Grishok A., Timmons L., Fire A., Mello C. C. The rde-1 gene, RNA interference, and transposon silencing in C. elegans. Cell. 1999 Oct 15;99(2):123–132. doi: 10.1016/s0092-8674(00)81644-x. [DOI] [PubMed] [Google Scholar]
  27. Yang D., Lu H., Erickson J. W. Evidence that processed small dsRNAs may mediate sequence-specific mRNA degradation during RNAi in Drosophila embryos. Curr Biol. 2000 Oct 5;10(19):1191–1200. doi: 10.1016/s0960-9822(00)00732-6. [DOI] [PubMed] [Google Scholar]
  28. Zamore P. D., Tuschl T., Sharp P. A., Bartel D. P. RNAi: double-stranded RNA directs the ATP-dependent cleavage of mRNA at 21 to 23 nucleotide intervals. Cell. 2000 Mar 31;101(1):25–33. doi: 10.1016/S0092-8674(00)80620-0. [DOI] [PubMed] [Google Scholar]

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