Skip to main content
NCBI home page
Genetics logoLink to Genetics
. 1994 Apr;136(4):1245–1259. doi: 10.1093/genetics/136.4.1245

Heterogeneous Functional Ty1 Elements Are Abundant in the Saccharomyces Cerevisiae Genome

M J Curcio 1, D J Garfinkel 1
PMCID: PMC1205905  PMID: 8013902

Abstract

Despite the abundance of Ty1 RNA in Saccharomyces cerevisiae, Ty1 retrotransposition is a rare event. To determine whether transpositional dormancy is the result of defective Ty1 elements, functional and defective alleles of the retrotransposon in the yeast genome were quantitated. Genomic Ty1 elements were isolated by gap repair-mediated recombination of pGTy1-H3(Δ475-3944)HIS3, a multicopy plasmid containing a GAL1/Ty1-H3 fusion element lacking most of the gag domain (TYA) and the protease (PR) and integrase (IN) domains. Of 39 independent gap repaired pGTyHIS3 elements isolated, 29 (74%) transposed at high levels following galactose induction. The presence of restriction site polymorphisms within the gap repaired region of the 29 functional pGTyHIS3 elements indicated that they were derived from at least eight different genomic Ty1 elements and one Ty2 element. Of the 10 defective pGTyHIS3 elements, one was a partial gap repair event while the other nine were derived from at least six different genomic Ty1 elements. These results suggest that most genomic Ty1 elements encode functional TYA, PR and IN proteins. To understand how functional Ty1 elements are regulated, we tested the hypothesis that a TYB protein associates preferentially in cis with the RNA template that encodes it, thereby promoting transposition of its own element. A genomic Ty1 mhis3AI element containing either an in-frame insertion in PR or a deletion in TYB transposed at the same rate as a wild-type Ty1mhis3AI allele, indicating that TYB proteins act efficiently in trans. This result suggests in principle that defective genomic Ty1 elements could encode trans-acting repressors of transposition; however, expression of only one of the nine defective pGTy1 isolates had a negative effect on genomic Ty1 mhis3AI element transposition in trans, and this effect was modest. Therefore, the few defective Ty1 elements in the genome are not responsible for transpositional dormancy.

Full Text

The Full Text of this article is available as a PDF (8.3 MB).

Selected References

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

  1. Alani E., Cao L., Kleckner N. A method for gene disruption that allows repeated use of URA3 selection in the construction of multiply disrupted yeast strains. Genetics. 1987 Aug;116(4):541–545. doi: 10.1534/genetics.112.541.test. [DOI] [PMC free article] [PubMed] [Google Scholar]
  2. Boeke J. D., Eichinger D., Castrillon D., Fink G. R. The Saccharomyces cerevisiae genome contains functional and nonfunctional copies of transposon Ty1. Mol Cell Biol. 1988 Apr;8(4):1432–1442. doi: 10.1128/mcb.8.4.1432. [DOI] [PMC free article] [PubMed] [Google Scholar]
  3. 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]
  4. Boeke J. D., LaCroute F., Fink G. R. A positive selection for mutants lacking orotidine-5'-phosphate decarboxylase activity in yeast: 5-fluoro-orotic acid resistance. Mol Gen Genet. 1984;197(2):345–346. doi: 10.1007/BF00330984. [DOI] [PubMed] [Google Scholar]
  5. Clare J., Farabaugh P. Nucleotide sequence of a yeast Ty element: evidence for an unusual mechanism of gene expression. Proc Natl Acad Sci U S A. 1985 May;82(9):2829–2833. doi: 10.1073/pnas.82.9.2829. [DOI] [PMC free article] [PubMed] [Google Scholar]
  6. Curcio M. J., Garfinkel D. J. Posttranslational control of Ty1 retrotransposition occurs at the level of protein processing. Mol Cell Biol. 1992 Jun;12(6):2813–2825. doi: 10.1128/mcb.12.6.2813. [DOI] [PMC free article] [PubMed] [Google Scholar]
  7. Curcio M. J., Garfinkel D. J. Regulation of retrotransposition in Saccharomyces cerevisiae. Mol Microbiol. 1991 Aug;5(8):1823–1829. doi: 10.1111/j.1365-2958.1991.tb00806.x. [DOI] [PubMed] [Google Scholar]
  8. Curcio M. J., Hedge A. M., Boeke J. D., Garfinkel D. J. Ty RNA levels determine the spectrum of retrotransposition events that activate gene expression in Saccharomyces cerevisiae. Mol Gen Genet. 1990 Jan;220(2):213–221. doi: 10.1007/BF00260484. [DOI] [PubMed] [Google Scholar]
  9. Curcio M. J., Sanders N. J., Garfinkel D. J. Transpositional competence and transcription of endogenous Ty elements in Saccharomyces cerevisiae: implications for regulation of transposition. Mol Cell Biol. 1988 Sep;8(9):3571–3581. doi: 10.1128/mcb.8.9.3571. [DOI] [PMC free article] [PubMed] [Google Scholar]
  10. Derr L. K., Strathern J. N. A role for reverse transcripts in gene conversion. Nature. 1993 Jan 14;361(6408):170–173. doi: 10.1038/361170a0. [DOI] [PubMed] [Google Scholar]
  11. 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]
  12. Elder R. T., St John T. P., Stinchcomb D. T., Davis R. W., Scherer S., Davis R. W. Studies on the transposable element Ty1 of yeast. I. RNA homologous to Ty1. II. Recombination and expression of Ty1 and adjacent sequences. Cold Spring Harb Symp Quant Biol. 1981;45(Pt 2):581–591. doi: 10.1101/sqb.1981.045.01.075. [DOI] [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. Garfinkel D. J., Curcio M. J., Youngren S. D., Sanders N. J. The biology and exploitation of the retrotransposon Ty in Saccharomyces cerevisiae. Genome. 1989;31(2):909–919. doi: 10.1139/g89-162. [DOI] [PubMed] [Google Scholar]
  15. Garfinkel D. J., Mastrangelo M. F., Sanders N. J., Shafer B. K., Strathern J. N. Transposon tagging using Ty elements in yeast. Genetics. 1988 Sep;120(1):95–108. doi: 10.1093/genetics/120.1.95. [DOI] [PMC free article] [PubMed] [Google Scholar]
  16. Gietz D., St Jean A., Woods R. A., Schiestl R. H. Improved method for high efficiency transformation of intact yeast cells. Nucleic Acids Res. 1992 Mar 25;20(6):1425–1425. doi: 10.1093/nar/20.6.1425. [DOI] [PMC free article] [PubMed] [Google Scholar]
  17. Hansen L. J., Chalker D. L., Sandmeyer S. B. Ty3, a yeast retrotransposon associated with tRNA genes, has homology to animal retroviruses. Mol Cell Biol. 1988 Dec;8(12):5245–5256. doi: 10.1128/mcb.8.12.5245. [DOI] [PMC free article] [PubMed] [Google Scholar]
  18. Ho S. N., Hunt H. D., Horton R. M., Pullen J. K., Pease L. R. Site-directed mutagenesis by overlap extension using the polymerase chain reaction. Gene. 1989 Apr 15;77(1):51–59. doi: 10.1016/0378-1119(89)90358-2. [DOI] [PubMed] [Google Scholar]
  19. Janetzky B., Lehle L. Ty4, a new retrotransposon from Saccharomyces cerevisiae, flanked by tau-elements. J Biol Chem. 1992 Oct 5;267(28):19798–19805. [PubMed] [Google Scholar]
  20. Keil R. L., Roeder G. S. Cis-acting, recombination-stimulating activity in a fragment of the ribosomal DNA of S. cerevisiae. Cell. 1984 Dec;39(2 Pt 1):377–386. doi: 10.1016/0092-8674(84)90016-3. [DOI] [PubMed] [Google Scholar]
  21. Kingsman A. J., Gimlich R. L., Clarke L., Chinault A. C., Carbon J. Sequence variation in dispersed repetitive sequences in Saccharomyces cerevisiae. J Mol Biol. 1981 Feb 5;145(4):619–632. doi: 10.1016/0022-2836(81)90306-5. [DOI] [PubMed] [Google Scholar]
  22. Kupiec M., Petes T. D. Meiotic recombination between repeated transposable elements in Saccharomyces cerevisiae. Mol Cell Biol. 1988 Jul;8(7):2942–2954. doi: 10.1128/mcb.8.7.2942. [DOI] [PMC free article] [PubMed] [Google Scholar]
  23. McFall E. cis-acting proteins. J Bacteriol. 1986 Aug;167(2):429–432. doi: 10.1128/jb.167.2.429-432.1986. [DOI] [PMC free article] [PubMed] [Google Scholar]
  24. Melamed C., Nevo Y., Kupiec M. Involvement of cDNA in homologous recombination between Ty elements in Saccharomyces cerevisiae. Mol Cell Biol. 1992 Apr;12(4):1613–1620. doi: 10.1128/mcb.12.4.1613. [DOI] [PMC free article] [PubMed] [Google Scholar]
  25. Monokian G. M., Braiterman L. T., Boeke J. D. In-frame linker insertion mutagenesis of yeast transposon Ty1: mutations, transposition and dominance. Gene. 1994 Feb 11;139(1):9–18. doi: 10.1016/0378-1119(94)90517-7. [DOI] [PubMed] [Google Scholar]
  26. Orr-Weaver T. L., Szostak J. W. Yeast recombination: the association between double-strand gap repair and crossing-over. Proc Natl Acad Sci U S A. 1983 Jul;80(14):4417–4421. doi: 10.1073/pnas.80.14.4417. [DOI] [PMC free article] [PubMed] [Google Scholar]
  27. Paquin C. E., Williamson V. M. Temperature effects on the rate of ty transposition. Science. 1984 Oct 5;226(4670):53–55. doi: 10.1126/science.226.4670.53. [DOI] [PubMed] [Google Scholar]
  28. Picologlou S., Brown N., Liebman S. W. Mutations in RAD6, a yeast gene encoding a ubiquitin-conjugating enzyme, stimulate retrotransposition. Mol Cell Biol. 1990 Mar;10(3):1017–1022. doi: 10.1128/mcb.10.3.1017. [DOI] [PMC free article] [PubMed] [Google Scholar]
  29. Rio D. C. Regulation of Drosophila P element transposition. Trends Genet. 1991 Sep;7(9):282–287. doi: 10.1016/0168-9525(91)90309-E. [DOI] [PubMed] [Google Scholar]
  30. Simchen G., Winston F., Styles C. A., Fink G. R. Ty-mediated gene expression of the LYS2 and HIS4 genes of Saccharomyces cerevisiae is controlled by the same SPT genes. Proc Natl Acad Sci U S A. 1984 Apr;81(8):2431–2434. doi: 10.1073/pnas.81.8.2431. [DOI] [PMC free article] [PubMed] [Google Scholar]
  31. Temin H. M. Retrovirus variation and reverse transcription: abnormal strand transfers result in retrovirus genetic variation. Proc Natl Acad Sci U S A. 1993 Aug 1;90(15):6900–6903. doi: 10.1073/pnas.90.15.6900. [DOI] [PMC free article] [PubMed] [Google Scholar]
  32. Voelkel-Meiman K., Keil R. L., Roeder G. S. Recombination-stimulating sequences in yeast ribosomal DNA correspond to sequences regulating transcription by RNA polymerase I. Cell. 1987 Mar 27;48(6):1071–1079. doi: 10.1016/0092-8674(87)90714-8. [DOI] [PubMed] [Google Scholar]
  33. Voytas D. F., Boeke J. D. Yeast retrotransposon revealed. Nature. 1992 Aug 27;358(6389):717–717. doi: 10.1038/358717a0. [DOI] [PubMed] [Google Scholar]
  34. Warmington J. R., Waring R. B., Newlon C. S., Indge K. J., Oliver S. G. Nucleotide sequence characterization of Ty 1-17, a class II transposon from yeast. Nucleic Acids Res. 1985 Sep 25;13(18):6679–6693. doi: 10.1093/nar/13.18.6679. [DOI] [PMC free article] [PubMed] [Google Scholar]
  35. White M. A., Detloff P., Strand M., Petes T. D. A promoter deletion reduces the rate of mitotic, but not meiotic, recombination at the HIS4 locus in yeast. Curr Genet. 1992 Feb;21(2):109–116. doi: 10.1007/BF00318468. [DOI] [PubMed] [Google Scholar]
  36. Wilke C. M., Adams J. Fitness effects of Ty transposition in Saccharomyces cerevisiae. Genetics. 1992 May;131(1):31–42. doi: 10.1093/genetics/131.1.31. [DOI] [PMC free article] [PubMed] [Google Scholar]
  37. Wilke C. M., Heidler S. H., Brown N., Liebman S. W. Analysis of yeast retrotransposon Ty insertions at the CAN1 locus. Genetics. 1989 Dec;123(4):655–665. doi: 10.1093/genetics/123.4.655. [DOI] [PMC free article] [PubMed] [Google Scholar]
  38. Winston F., Durbin K. J., Fink G. R. The SPT3 gene is required for normal transcription of Ty elements in S. cerevisiae. Cell. 1984 Dec;39(3 Pt 2):675–682. doi: 10.1016/0092-8674(84)90474-4. [DOI] [PubMed] [Google Scholar]
  39. 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]

Articles from Genetics are provided here courtesy of Oxford University Press

RESOURCES