Skip to main content
NCBI home page
Journal of Virology logoLink to Journal of Virology
. 1992 Mar;66(3):1590–1601. doi: 10.1128/jvi.66.3.1590-1601.1992

The baculovirus-integrated retrotransposon TED encodes gag and pol proteins that assemble into viruslike particles with reverse transcriptase.

R A Lerch 1, P D Friesen 1
PMCID: PMC240890  PMID: 1371168

Abstract

TED is a lepidopteran retrotransposon found inserted within the DNA genome of the Autographa californica nuclear polyhedrosis virus mutant, FP-D. To examine the proteins and functions encoded by this representative of the gypsy family of retrotransposons, the gag- and pol-like open reading frames (ORFs 1 and 2) were expressed in homologous lepidopteran cells by using recombinant baculovirus vectors. Expression of ORF 1 resulted in synthesis of an abundant TED-specific protein (Pr55gag) that assembled into viruslike particles with a diameter of 55 to 60 nm. Expression of ORF 2, requiring a -1 translational frameshift, resulted in synthesis of a protease that mediated cleavage of Pr55gag to generate p37, the major protein component of the resulting particles. Expression of ORF 2 also produced reverse transcriptase that associated with these particles. Both protease and reverse transcriptase activities mapped to domains within ORF 2 that contain sequence similarities with the corresponding functional domains of the pol gene of the vertebrate retroviruses. These results indicated that TED ORFs 1 and 2 functionally resemble the retrovirus gag and pol genes and demonstrated for the first time that an invertebrate member of the gypsy family of elements encodes active forms of the structural and enzymatic functions necessary for transposition via an RNA intermediate. TED integration within the baculovirus genome thus represents one of the first examples of transposon-mediated transfer of host-derived genes to an eukaryotic virus.

Full text

PDF
1590

Images in this article

1594Image
on p.1594
1595Image
on p.1595
1595Image
on p.1595
1596Image
on p.1596
1597Image
on p.1597
1598Image
on p.1598

Selected References

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

  1. Adams S. E., Mellor J., Gull K., Sim R. B., Tuite M. F., Kingsman S. M., Kingsman A. J. The functions and relationships of Ty-VLP proteins in yeast reflect those of mammalian retroviral proteins. Cell. 1987 Apr 10;49(1):111–119. doi: 10.1016/0092-8674(87)90761-6. [DOI] [PubMed] [Google Scholar]
  2. Beames B., Summers M. D. Sequence comparison of cellular and viral copies of host cell DNA insertions found in Autographa californica nuclear polyhedrosis virus. Virology. 1990 Feb;174(2):354–363. doi: 10.1016/0042-6822(90)90089-a. [DOI] [PubMed] [Google Scholar]
  3. Blissard G. W., Rohrmann G. F. Baculovirus diversity and molecular biology. Annu Rev Entomol. 1990;35:127–155. doi: 10.1146/annurev.en.35.010190.001015. [DOI] [PubMed] [Google Scholar]
  4. Boeke J. D., Corces V. G. Transcription and reverse transcription of retrotransposons. Annu Rev Microbiol. 1989;43:403–434. doi: 10.1146/annurev.mi.43.100189.002155. [DOI] [PubMed] [Google Scholar]
  5. Boeke J. D., Garfinkel D. J., Styles C. A., Fink G. R. Ty elements transpose through an RNA intermediate. Cell. 1985 Mar;40(3):491–500. doi: 10.1016/0092-8674(85)90197-7. [DOI] [PubMed] [Google Scholar]
  6. Cary L. C., Goebel M., Corsaro B. G., Wang H. G., Rosen E., Fraser M. J. Transposon mutagenesis of baculoviruses: analysis of Trichoplusia ni transposon IFP2 insertions within the FP-locus of nuclear polyhedrosis viruses. Virology. 1989 Sep;172(1):156–169. doi: 10.1016/0042-6822(89)90117-7. [DOI] [PubMed] [Google Scholar]
  7. Delchambre M., Gheysen D., Thines D., Thiriart C., Jacobs E., Verdin E., Horth M., Burny A., Bex F. The GAG precursor of simian immunodeficiency virus assembles into virus-like particles. EMBO J. 1989 Sep;8(9):2653–2660. doi: 10.1002/j.1460-2075.1989.tb08405.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
  8. Echalier G. Drosophila retrotransposons: interactions with genome. Adv Virus Res. 1989;36:33–105. doi: 10.1016/s0065-3527(08)60582-5. [DOI] [PubMed] [Google Scholar]
  9. Eichinger D. J., Boeke J. D. The DNA intermediate in yeast Ty1 element transposition copurifies with virus-like particles: cell-free Ty1 transposition. Cell. 1988 Sep 23;54(7):955–966. doi: 10.1016/0092-8674(88)90110-9. [DOI] [PubMed] [Google Scholar]
  10. Friesen P. D., Miller L. K. Temporal regulation of baculovirus RNA: overlapping early and late transcripts. J Virol. 1985 May;54(2):392–400. doi: 10.1128/jvi.54.2.392-400.1985. [DOI] [PMC free article] [PubMed] [Google Scholar]
  11. Friesen P. D., Nissen M. S. Gene organization and transcription of TED, a lepidopteran retrotransposon integrated within the baculovirus genome. Mol Cell Biol. 1990 Jun;10(6):3067–3077. doi: 10.1128/mcb.10.6.3067. [DOI] [PMC free article] [PubMed] [Google Scholar]
  12. Friesen P. D., Rice W. C., Miller D. W., Miller L. K. Bidirectional transcription from a solo long terminal repeat of the retrotransposon TED: symmetrical RNA start sites. Mol Cell Biol. 1986 May;6(5):1599–1607. doi: 10.1128/mcb.6.5.1599. [DOI] [PMC free article] [PubMed] [Google Scholar]
  13. Garfinkel D. J., Boeke J. D., Fink G. R. Ty element transposition: reverse transcriptase and virus-like particles. Cell. 1985 Sep;42(2):507–517. doi: 10.1016/0092-8674(85)90108-4. [DOI] [PubMed] [Google Scholar]
  14. Gheysen D., Jacobs E., de Foresta F., Thiriart C., Francotte M., Thines D., De Wilde M. Assembly and release of HIV-1 precursor Pr55gag virus-like particles from recombinant baculovirus-infected insect cells. Cell. 1989 Oct 6;59(1):103–112. doi: 10.1016/0092-8674(89)90873-8. [DOI] [PubMed] [Google Scholar]
  15. Heine C. W., Kelly D. C., Avery R. J. The detection of intracellular retrovirus-like entities in Drosophila melanogaster cell cultures. J Gen Virol. 1980 Aug;49(2):385–395. doi: 10.1099/0022-1317-49-2-385. [DOI] [PubMed] [Google Scholar]
  16. Hink W. F. Established insect cell line from the cabbage looper, Trichoplusia ni. Nature. 1970 May 2;226(5244):466–467. doi: 10.1038/226466b0. [DOI] [PubMed] [Google Scholar]
  17. Jacks T., Madhani H. D., Masiarz F. R., Varmus H. E. Signals for ribosomal frameshifting in the Rous sarcoma virus gag-pol region. Cell. 1988 Nov 4;55(3):447–458. doi: 10.1016/0092-8674(88)90031-1. [DOI] [PMC free article] [PubMed] [Google Scholar]
  18. Katoh I., Yasunaga T., Ikawa Y., Yoshinaka Y. Inhibition of retroviral protease activity by an aspartyl proteinase inhibitor. Nature. 1987 Oct 15;329(6140):654–656. doi: 10.1038/329654a0. [DOI] [PubMed] [Google Scholar]
  19. Kingsman A. J., Kingsman S. M. Ty: a retroelement moving forward. Cell. 1988 May 6;53(3):333–335. doi: 10.1016/0092-8674(88)90151-1. [DOI] [PubMed] [Google Scholar]
  20. Laemmli U. K. Cleavage of structural proteins during the assembly of the head of bacteriophage T4. Nature. 1970 Aug 15;227(5259):680–685. doi: 10.1038/227680a0. [DOI] [PubMed] [Google Scholar]
  21. Lambertsson A., Andersson S., Johansson T. Cloning and characterization of variable-sized gypsy mobile elements in Drosophila melanogaster. Plasmid. 1989 Jul;22(1):22–31. doi: 10.1016/0147-619x(89)90032-2. [DOI] [PubMed] [Google Scholar]
  22. Lee H. H., Miller L. K. Isolation of genotypic variants of Autographa californica nuclear polyhedrosis virus. J Virol. 1978 Sep;27(3):754–767. doi: 10.1128/jvi.27.3.754-767.1978. [DOI] [PMC free article] [PubMed] [Google Scholar]
  23. Malik A. N., McLean P. M., Roberts A., Barnett P. S., Demaine A. G., Banga J. P., McGregor A. M. A simple high yield method for the preparation of lambda gt10 DNA suitable for subcloning, amplification and direct sequencing. Nucleic Acids Res. 1990 Jul 11;18(13):4031–4032. doi: 10.1093/nar/18.13.4031. [DOI] [PMC free article] [PubMed] [Google Scholar]
  24. Mellor J., Malim M. H., Gull K., Tuite M. F., McCready S., Dibbayawan T., Kingsman S. M., Kingsman A. J. Reverse transcriptase activity and Ty RNA are associated with virus-like particles in yeast. Nature. 1985 Dec 12;318(6046):583–586. doi: 10.1038/318583a0. [DOI] [PubMed] [Google Scholar]
  25. Miller D. W., Miller L. K. A virus mutant with an insertion of a copia-like transposable element. Nature. 1982 Oct 7;299(5883):562–564. doi: 10.1038/299562a0. [DOI] [PubMed] [Google Scholar]
  26. Miller L. K. Baculoviruses as gene expression vectors. Annu Rev Microbiol. 1988;42:177–199. doi: 10.1146/annurev.mi.42.100188.001141. [DOI] [PubMed] [Google Scholar]
  27. Overton H. A., Fujii Y., Price I. R., Jones I. M. The protease and gag gene products of the human immunodeficiency virus: authentic cleavage and post-translational modification in an insect cell expression system. Virology. 1989 May;170(1):107–116. doi: 10.1016/0042-6822(89)90357-7. [DOI] [PubMed] [Google Scholar]
  28. Peifer M., Bender W. Sequences of the gypsy transposon of Drosophila necessary for its effects on adjacent genes. Proc Natl Acad Sci U S A. 1988 Dec;85(24):9650–9654. doi: 10.1073/pnas.85.24.9650. [DOI] [PMC free article] [PubMed] [Google Scholar]
  29. Sanger F., Nicklen S., Coulson A. R. DNA sequencing with chain-terminating inhibitors. Proc Natl Acad Sci U S A. 1977 Dec;74(12):5463–5467. doi: 10.1073/pnas.74.12.5463. [DOI] [PMC free article] [PubMed] [Google Scholar]
  30. Shiba T., Saigo K. Retrovirus-like particles containing RNA homologous to the transposable element copia in Drosophila melanogaster. Nature. 1983 Mar 10;302(5904):119–124. doi: 10.1038/302119a0. [DOI] [PubMed] [Google Scholar]
  31. Temin H. M. Origin of retroviruses from cellular moveable genetic elements. Cell. 1980 Oct;21(3):599–600. doi: 10.1016/0092-8674(80)90420-1. [DOI] [PubMed] [Google Scholar]
  32. Toh H., Kikuno R., Hayashida H., Miyata T., Kugimiya W., Inouye S., Yuki S., Saigo K. Close structural resemblance between putative polymerase of a Drosophila transposable genetic element 17.6 and pol gene product of Moloney murine leukaemia virus. EMBO J. 1985 May;4(5):1267–1272. doi: 10.1002/j.1460-2075.1985.tb03771.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
  33. Vaughn J. L., Goodwin R. H., Tompkins G. J., McCawley P. The establishment of two cell lines from the insect Spodoptera frugiperda (Lepidoptera; Noctuidae). In Vitro. 1977 Apr;13(4):213–217. doi: 10.1007/BF02615077. [DOI] [PubMed] [Google Scholar]
  34. Wang H. H., Fraser M. J., Cary L. C. Transposon mutagenesis of baculoviruses: analysis of TFP3 lepidopteran transposon insertions at the FP locus of nuclear polyhedrosis viruses. Gene. 1989 Sep 1;81(1):97–108. doi: 10.1016/0378-1119(89)90340-5. [DOI] [PubMed] [Google Scholar]
  35. Xiong Y., Eickbush T. H. Origin and evolution of retroelements based upon their reverse transcriptase sequences. EMBO J. 1990 Oct;9(10):3353–3362. doi: 10.1002/j.1460-2075.1990.tb07536.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
  36. Youngren S. D., Boeke J. D., Sanders N. J., Garfinkel D. J. Functional organization of the retrotransposon Ty from Saccharomyces cerevisiae: Ty protease is required for transposition. Mol Cell Biol. 1988 Apr;8(4):1421–1431. doi: 10.1128/mcb.8.4.1421. [DOI] [PMC free article] [PubMed] [Google Scholar]
  37. ten Dam E. B., Pleij C. W., Bosch L. RNA pseudoknots: translational frameshifting and readthrough on viral RNAs. Virus Genes. 1990 Jul;4(2):121–136. doi: 10.1007/BF00678404. [DOI] [PMC free article] [PubMed] [Google Scholar]

Articles from Journal of Virology are provided here courtesy of American Society for Microbiology (ASM)

RESOURCES