Skip to main content
PMC home page
Molecular and Cellular Biology logoLink to Molecular and Cellular Biology
. 1995 May;15(5):2763–2771. doi: 10.1128/mcb.15.5.2763

Decoying the cap- mRNA degradation system by a double-stranded RNA virus and poly(A)- mRNA surveillance by a yeast antiviral system.

D C Masison 1, A Blanc 1, J C Ribas 1, K Carroll 1, N Sonenberg 1, R B Wickner 1
PMCID: PMC230507  PMID: 7739557

Abstract

The major coat protein of the L-A double-stranded RNA virus of Saccharomyces cerevisiae covalently binds m7 GMP from 5' capped mRNAs in vitro. We show that this cap binding also occurs in vivo and that, while this activity is required for expression of viral information (killer toxin mRNA level and toxin production) in a wild-type strain, this requirement is suppressed by deletion of SKI1/XRN1/SEP1. We propose that the virus creates decapped cellular mRNAs to decoy the 5'-->3' exoribonuclease specific for cap- RNA encoded by XRN1. The SKI2 antiviral gene represses the copy numbers of the L-A and L-BC viruses and the 20S RNA replicon, apparently by specifically blocking translation of viral RNA. We show that SKI2, SKI3, and SKI8 inhibit translation of electroporated luciferase and beta-glucuronidase mRNAs in vivo, but only if they lack the 3' poly(A) structure. Thus, L-A decoys the SKI1/XRN1/SEP1 exonuclease directed at 5' uncapped ends, but translation of the L-A poly(A)- mRNA is repressed by Ski2,3,8p. The SKI2-SKI3-SKI8 system is more effective against cap+ poly(A)- mRNA, suggesting a (nonessential) role in blocking translation of fragmented cellular mRNAs.

Full Text

The Full Text of this article is available as a PDF (360.5 KB).

Selected References

These references are in PubMed. This may not be the complete list of references from this article.

  1. Ball S. G., Tirtiaux C., Wickner R. B. Genetic Control of L-a and L-(Bc) Dsrna Copy Number in Killer Systems of SACCHAROMYCES CEREVISIAE. Genetics. 1984 Jun;107(2):199–217. doi: 10.1093/genetics/107.2.199. [DOI] [PMC free article] [PubMed] [Google Scholar]
  2. Bishop D. H., Gay M. E., Matsuoko Y. Nonviral heterogeneous sequences are present at the 5' ends of one species of snowshoe hare bunyavirus S complementary RNA. Nucleic Acids Res. 1983 Sep 24;11(18):6409–6418. doi: 10.1093/nar/11.18.6409. [DOI] [PMC free article] [PubMed] [Google Scholar]
  3. Blanc A., Goyer C., Sonenberg N. The coat protein of the yeast double-stranded RNA virus L-A attaches covalently to the cap structure of eukaryotic mRNA. Mol Cell Biol. 1992 Aug;12(8):3390–3398. doi: 10.1128/mcb.12.8.3390. [DOI] [PMC free article] [PubMed] [Google Scholar]
  4. Blanc A., Ribas J. C., Wickner R. B., Sonenberg N. His-154 is involved in the linkage of the Saccharomyces cerevisiae L-A double-stranded RNA virus Gag protein to the cap structure of mRNAs and is essential for M1 satellite virus expression. Mol Cell Biol. 1994 Apr;14(4):2664–2674. doi: 10.1128/mcb.14.4.2664. [DOI] [PMC free article] [PubMed] [Google Scholar]
  5. Bouloy M., Plotch S. J., Krug R. M. Globin mRNAs are primers for the transcription of influenza viral RNA in vitro. Proc Natl Acad Sci U S A. 1978 Oct;75(10):4886–4890. doi: 10.1073/pnas.75.10.4886. [DOI] [PMC free article] [PubMed] [Google Scholar]
  6. Bruenn J. A., Brennan V. E. Yeast viral double-stranded RNAs have heterogeneous 3' termini. Cell. 1980 Apr;19(4):923–933. doi: 10.1016/0092-8674(80)90084-7. [DOI] [PubMed] [Google Scholar]
  7. Bruenn J., Keitz B. The 5' ends of yeast killer factor RNAs are pppGp. Nucleic Acids Res. 1976 Oct;3(10):2427–2436. doi: 10.1093/nar/3.10.2427. [DOI] [PMC free article] [PubMed] [Google Scholar]
  8. Bussey H. K1 killer toxin, a pore-forming protein from yeast. Mol Microbiol. 1991 Oct;5(10):2339–2343. doi: 10.1111/j.1365-2958.1991.tb02079.x. [DOI] [PubMed] [Google Scholar]
  9. Carter C., Stoltzfus C. M., Banerjee A. K., Shatkin A. J. Origin of reovirus oligo(A). J Virol. 1974 Jun;13(6):1331–1337. doi: 10.1128/jvi.13.6.1331-1337.1974. [DOI] [PMC free article] [PubMed] [Google Scholar]
  10. Cleveland D. R., Zarbl H., Millward S. Reovirus guanylyltransferase is L2 gene product lambda 2. J Virol. 1986 Oct;60(1):307–311. doi: 10.1128/jvi.60.1.307-311.1986. [DOI] [PMC free article] [PubMed] [Google Scholar]
  11. Dihanich M., van Tuinen E., Lambris J. D., Marshallsay B. Accumulation of viruslike particles in a yeast mutant lacking a mitochondrial pore protein. Mol Cell Biol. 1989 Mar;9(3):1100–1108. doi: 10.1128/mcb.9.3.1100. [DOI] [PMC free article] [PubMed] [Google Scholar]
  12. Dinman J. D., Icho T., Wickner R. B. A -1 ribosomal frameshift in a double-stranded RNA virus of yeast forms a gag-pol fusion protein. Proc Natl Acad Sci U S A. 1991 Jan 1;88(1):174–178. doi: 10.1073/pnas.88.1.174. [DOI] [PMC free article] [PubMed] [Google Scholar]
  13. Esteban R., Wickner R. B. A new non-mendelian genetic element of yeast that increases cytopathology produced by M1 double-stranded RNA in ski strains. Genetics. 1987 Nov;117(3):399–408. doi: 10.1093/genetics/117.3.399. [DOI] [PMC free article] [PubMed] [Google Scholar]
  14. Everett J. G., Gallie D. R. RNA delivery in Saccharomyces cerevisiae using electroporation. Yeast. 1992 Dec;8(12):1007–1014. doi: 10.1002/yea.320081203. [DOI] [PubMed] [Google Scholar]
  15. Fujimura T., Esteban R., Wickner R. B. In vitro L-A double-stranded RNA synthesis in virus-like particles from Saccharomyces cerevisiae. Proc Natl Acad Sci U S A. 1986 Jun;83(12):4433–4437. doi: 10.1073/pnas.83.12.4433. [DOI] [PMC free article] [PubMed] [Google Scholar]
  16. Fujimura T., Wickner R. B. Gene overlap results in a viral protein having an RNA binding domain and a major coat protein domain. Cell. 1988 Nov 18;55(4):663–671. doi: 10.1016/0092-8674(88)90225-5. [DOI] [PubMed] [Google Scholar]
  17. Fujimura T., Wickner R. B. L-A double-stranded RNA viruslike particle replication cycle in Saccharomyces cerevisiae: particle maturation in vitro and effects of mak10 and pet18 mutations. Mol Cell Biol. 1987 Jan;7(1):420–426. doi: 10.1128/mcb.7.1.420. [DOI] [PMC free article] [PubMed] [Google Scholar]
  18. Furuichi Y., Muthukrishnan S., Tomasz J., Shatkin A. J. Mechanism of formation of reovirus mRNA 5'-terminal blocked and methylated sequence, m7GpppGmpC. J Biol Chem. 1976 Aug 25;251(16):5043–5053. [PubMed] [Google Scholar]
  19. Gallie D. R., Feder J. N., Schimke R. T., Walbot V. Post-transcriptional regulation in higher eukaryotes: the role of the reporter gene in controlling expression. Mol Gen Genet. 1991 Aug;228(1-2):258–264. doi: 10.1007/BF00282474. [DOI] [PubMed] [Google Scholar]
  20. Gallie D. R. The cap and poly(A) tail function synergistically to regulate mRNA translational efficiency. Genes Dev. 1991 Nov;5(11):2108–2116. doi: 10.1101/gad.5.11.2108. [DOI] [PubMed] [Google Scholar]
  21. Hartwell L. H., McLaughlin C. S. Temperature-sensitive mutants of yeast exhibiting a rapid inhibition of protein synthesis. J Bacteriol. 1968 Nov;96(5):1664–1671. doi: 10.1128/jb.96.5.1664-1671.1968. [DOI] [PMC free article] [PubMed] [Google Scholar]
  22. Hsu C. L., Stevens A. Yeast cells lacking 5'-->3' exoribonuclease 1 contain mRNA species that are poly(A) deficient and partially lack the 5' cap structure. Mol Cell Biol. 1993 Aug;13(8):4826–4835. doi: 10.1128/mcb.13.8.4826. [DOI] [PMC free article] [PubMed] [Google Scholar]
  23. Icho T., Wickner R. B. The double-stranded RNA genome of yeast virus L-A encodes its own putative RNA polymerase by fusing two open reading frames. J Biol Chem. 1989 Apr 25;264(12):6716–6723. [PubMed] [Google Scholar]
  24. Jackson R. J., Standart N. Do the poly(A) tail and 3' untranslated region control mRNA translation? Cell. 1990 Jul 13;62(1):15–24. doi: 10.1016/0092-8674(90)90235-7. [DOI] [PubMed] [Google Scholar]
  25. Jang S. K., Kräusslich H. G., Nicklin M. J., Duke G. M., Palmenberg A. C., Wimmer E. A segment of the 5' nontranslated region of encephalomyocarditis virus RNA directs internal entry of ribosomes during in vitro translation. J Virol. 1988 Aug;62(8):2636–2643. doi: 10.1128/jvi.62.8.2636-2643.1988. [DOI] [PMC free article] [PubMed] [Google Scholar]
  26. Kim J., Ljungdahl P. O., Fink G. R. kem mutations affect nuclear fusion in Saccharomyces cerevisiae. Genetics. 1990 Dec;126(4):799–812. doi: 10.1093/genetics/126.4.799. [DOI] [PMC free article] [PubMed] [Google Scholar]
  27. Kipling D., Tambini C., Kearsey S. E. rar mutations which increase artificial chromosome stability in Saccharomyces cerevisiae identify transcription and recombination proteins. Nucleic Acids Res. 1991 Apr 11;19(7):1385–1391. doi: 10.1093/nar/19.7.1385. [DOI] [PMC free article] [PubMed] [Google Scholar]
  28. Larimer F. W., Hsu C. L., Maupin M. K., Stevens A. Characterization of the XRN1 gene encoding a 5'-->3' exoribonuclease: sequence data and analysis of disparate protein and mRNA levels of gene-disrupted yeast cells. Gene. 1992 Oct 12;120(1):51–57. doi: 10.1016/0378-1119(92)90008-d. [DOI] [PubMed] [Google Scholar]
  29. Lejbkowicz F., Goyer C., Darveau A., Neron S., Lemieux R., Sonenberg N. A fraction of the mRNA 5' cap-binding protein, eukaryotic initiation factor 4E, localizes to the nucleus. Proc Natl Acad Sci U S A. 1992 Oct 15;89(20):9612–9616. doi: 10.1073/pnas.89.20.9612. [DOI] [PMC free article] [PubMed] [Google Scholar]
  30. Liu D. X., Inglis S. C. Internal entry of ribosomes on a tricistronic mRNA encoded by infectious bronchitis virus. J Virol. 1992 Oct;66(10):6143–6154. doi: 10.1128/jvi.66.10.6143-6154.1992. [DOI] [PMC free article] [PubMed] [Google Scholar]
  31. Matsumoto Y., Fishel R., Wickner R. B. Circular single-stranded RNA replicon in Saccharomyces cerevisiae. Proc Natl Acad Sci U S A. 1990 Oct;87(19):7628–7632. doi: 10.1073/pnas.87.19.7628. [DOI] [PMC free article] [PubMed] [Google Scholar]
  32. Matsumoto Y., Sarkar G., Sommer S. S., Wickner R. B. A yeast antiviral protein, SKI8, shares a repeated amino acid sequence pattern with beta-subunits of G proteins and several other proteins. Yeast. 1993 Jan;9(1):43–51. doi: 10.1002/yea.320090106. [DOI] [PubMed] [Google Scholar]
  33. Matsumoto Y., Wickner R. B. Yeast 20 S RNA replicon. Replication intermediates and encoded putative RNA polymerase. J Biol Chem. 1991 Jul 5;266(19):12779–12783. [PubMed] [Google Scholar]
  34. Muhlrad D., Parker R. Premature translational termination triggers mRNA decapping. Nature. 1994 Aug 18;370(6490):578–581. doi: 10.1038/370578a0. [DOI] [PubMed] [Google Scholar]
  35. Munroe D., Jacobson A. Tales of poly(A): a review. Gene. 1990 Jul 16;91(2):151–158. doi: 10.1016/0378-1119(90)90082-3. [DOI] [PubMed] [Google Scholar]
  36. Nemeroff M. E., Bruenn J. A. Initiation by the yeast viral transcriptase in vitro. J Biol Chem. 1987 May 15;262(14):6785–6787. [PubMed] [Google Scholar]
  37. Ohtake Y., Wickner R. B. Yeast virus propagation depends critically on free 60S ribosomal subunit concentration. Mol Cell Biol. 1995 May;15(5):2772–2781. doi: 10.1128/mcb.15.5.2772. [DOI] [PMC free article] [PubMed] [Google Scholar]
  38. Patterson J. L., Holloway B., Kolakofsky D. La Crosse virions contain a primer-stimulated RNA polymerase and a methylated cap-dependent endonuclease. J Virol. 1984 Oct;52(1):215–222. doi: 10.1128/jvi.52.1.215-222.1984. [DOI] [PMC free article] [PubMed] [Google Scholar]
  39. Pelletier J., Sonenberg N. Internal initiation of translation of eukaryotic mRNA directed by a sequence derived from poliovirus RNA. Nature. 1988 Jul 28;334(6180):320–325. doi: 10.1038/334320a0. [DOI] [PubMed] [Google Scholar]
  40. Plotch S. J., Bouloy M., Ulmanen I., Krug R. M. A unique cap(m7GpppXm)-dependent influenza virion endonuclease cleaves capped RNAs to generate the primers that initiate viral RNA transcription. Cell. 1981 Mar;23(3):847–858. doi: 10.1016/0092-8674(81)90449-9. [DOI] [PubMed] [Google Scholar]
  41. Rhee S. K., Icho T., Wickner R. B. Structure and nuclear localization signal of the SKI3 antiviral protein of Saccharomyces cerevisiae. Yeast. 1989 May-Jun;5(3):149–158. doi: 10.1002/yea.320050304. [DOI] [PubMed] [Google Scholar]
  42. Ridley S. P., Sommer S. S., Wickner R. B. Superkiller mutations in Saccharomyces cerevisiae suppress exclusion of M2 double-stranded RNA by L-A-HN and confer cold sensitivity in the presence of M and L-A-HN. Mol Cell Biol. 1984 Apr;4(4):761–770. doi: 10.1128/mcb.4.4.761. [DOI] [PMC free article] [PubMed] [Google Scholar]
  43. Russell P. J., Hambidge S. J., Kirkegaard K. Direct introduction and transient expression of capped and non-capped RNA in Saccharomyces cerevisiae. Nucleic Acids Res. 1991 Sep 25;19(18):4949–4953. doi: 10.1093/nar/19.18.4949. [DOI] [PMC free article] [PubMed] [Google Scholar]
  44. Sachs A. B., Davis R. W. The poly(A) binding protein is required for poly(A) shortening and 60S ribosomal subunit-dependent translation initiation. Cell. 1989 Sep 8;58(5):857–867. doi: 10.1016/0092-8674(89)90938-0. [DOI] [PubMed] [Google Scholar]
  45. Scheidel L. M., Durbin R. K., Stollar V. SVLM21, a Sindbis virus mutant resistant to methionine deprivation, encodes an altered methyltransferase. Virology. 1989 Dec;173(2):408–414. doi: 10.1016/0042-6822(89)90553-9. [DOI] [PubMed] [Google Scholar]
  46. Sikorski R. S., Boguski M. S., Goebl M., Hieter P. A repeating amino acid motif in CDC23 defines a family of proteins and a new relationship among genes required for mitosis and RNA synthesis. Cell. 1990 Jan 26;60(2):307–317. doi: 10.1016/0092-8674(90)90745-z. [DOI] [PubMed] [Google Scholar]
  47. Sommer S. S., Wickner R. B. Gene disruption indicates that the only essential function of the SKI8 chromosomal gene is to protect Saccharomyces cerevisiae from viral cytopathology. Virology. 1987 Mar;157(1):252–256. doi: 10.1016/0042-6822(87)90338-2. [DOI] [PubMed] [Google Scholar]
  48. Sommer S. S., Wickner R. B. Yeast L dsRNA consists of at least three distinct RNAs; evidence that the non-Mendelian genes [HOK], [NEX] and [EXL] are on one of these dsRNAs. Cell. 1982 Dec;31(2 Pt 1):429–441. doi: 10.1016/0092-8674(82)90136-2. [DOI] [PubMed] [Google Scholar]
  49. Stevens A., Maupin M. K. A 5'----3' exoribonuclease of Saccharomyces cerevisiae: size and novel substrate specificity. Arch Biochem Biophys. 1987 Feb 1;252(2):339–347. doi: 10.1016/0003-9861(87)90040-3. [DOI] [PubMed] [Google Scholar]
  50. Stevens A. Purification and characterization of a Saccharomyces cerevisiae exoribonuclease which yields 5'-mononucleotides by a 5' leads to 3' mode of hydrolysis. J Biol Chem. 1980 Apr 10;255(7):3080–3085. [PubMed] [Google Scholar]
  51. Thiele D. J., Hannig E. M., Leibowitz M. J. Multiple L double-stranded RNA species of Saccharomyces cerevisiae: evidence for separate encapsidation. Mol Cell Biol. 1984 Jan;4(1):92–100. doi: 10.1128/mcb.4.1.92. [DOI] [PMC free article] [PubMed] [Google Scholar]
  52. Tishkoff D. X., Johnson A. W., Kolodner R. D. Molecular and genetic analysis of the gene encoding the Saccharomyces cerevisiae strand exchange protein Sep1. Mol Cell Biol. 1991 May;11(5):2593–2608. doi: 10.1128/mcb.11.5.2593. [DOI] [PMC free article] [PubMed] [Google Scholar]
  53. Toh-E A., Guerry P., Wickner R. B. Chromosomal superkiller mutants of Saccharomyces cerevisiae. J Bacteriol. 1978 Dec;136(3):1002–1007. doi: 10.1128/jb.136.3.1002-1007.1978. [DOI] [PMC free article] [PubMed] [Google Scholar]
  54. Toh-E A., Wickner R. B. "Superkiller" mutations suppress chromosomal mutations affecting double-stranded RNA killer plasmid replication in saccharomyces cerevisiae. Proc Natl Acad Sci U S A. 1980 Jan;77(1):527–530. doi: 10.1073/pnas.77.1.527. [DOI] [PMC free article] [PubMed] [Google Scholar]
  55. Wickner R. B. Double-stranded and single-stranded RNA viruses of Saccharomyces cerevisiae. Annu Rev Microbiol. 1992;46:347–375. doi: 10.1146/annurev.mi.46.100192.002023. [DOI] [PubMed] [Google Scholar]
  56. Wickner R. B., Icho T., Fujimura T., Widner W. R. Expression of yeast L-A double-stranded RNA virus proteins produces derepressed replication: a ski- phenocopy. J Virol. 1991 Jan;65(1):155–161. doi: 10.1128/jvi.65.1.155-161.1991. [DOI] [PMC free article] [PubMed] [Google Scholar]
  57. Wickner R. B., Ridley S. P., Fried H. M., Ball S. G. Ribosomal protein L3 is involved in replication or maintenance of the killer double-stranded RNA genome of Saccharomyces cerevisiae. Proc Natl Acad Sci U S A. 1982 Aug;79(15):4706–4708. doi: 10.1073/pnas.79.15.4706. [DOI] [PMC free article] [PubMed] [Google Scholar]
  58. Widner W. R., Wickner R. B. Evidence that the SKI antiviral system of Saccharomyces cerevisiae acts by blocking expression of viral mRNA. Mol Cell Biol. 1993 Jul;13(7):4331–4341. doi: 10.1128/mcb.13.7.4331. [DOI] [PMC free article] [PubMed] [Google Scholar]
  59. Zhu Y. S., Kane J., Zhang X. Y., Zhang M., Tipper D. J. Role of the gamma component of preprotoxin in expression of the yeast K1 killer phenotype. Yeast. 1993 Mar;9(3):251–266. doi: 10.1002/yea.320090305. [DOI] [PubMed] [Google Scholar]

Articles from Molecular and Cellular Biology are provided here courtesy of Taylor & Francis

RESOURCES