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. 2000 Nov;156(3):1147–1155. doi: 10.1093/genetics/156.3.1147

New insights on homology-dependent silencing of I factor activity by transgenes containing ORF1 in Drosophila melanogaster.

S Malinsky 1, A Bucheton 1, I Busseau 1
PMCID: PMC1461323  PMID: 11063690

Abstract

I factors in Drosophila melanogaster are non-LTR retrotransposons that transpose at very high frequencies in the germ line of females resulting from crosses between reactive females (devoid of active I factors) and inducer males (containing active I factors). Constructs containing I factor ORF1 under the control of the hsp70 promoter repress I factor activity. This repressor effect is maternally transmitted and increases with the transgene copy number. It is irrespective of either frame integrity or transcriptional orientation of ORF1, suggesting the involvement of a homology-dependent trans-silencing mechanism. A promoterless transgene displays no repression. The effect of constructs in which ORF1 is controlled by the hsp70 promoter does not depend upon heat-shock treatments. No effect of ORF1 is detected when it is controlled by the I factor promoter. We discuss the relevance of the described regulation to the repression of I factors in I strains.

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Selected References

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  1. Abad P., Vaury C., Pélisson A., Chaboissier M. C., Busseau I., Bucheton A. A long interspersed repetitive element--the I factor of Drosophila teissieri--is able to transpose in different Drosophila species. Proc Natl Acad Sci U S A. 1989 Nov;86(22):8887–8891. doi: 10.1073/pnas.86.22.8887. [DOI] [PMC free article] [PubMed] [Google Scholar]
  2. Bouhidel K., Terzian C., Pinon H. The full-length transcript of the I factor, a LINE element of Drosophila melanogaster, is a potential bicistronic RNA messenger. Nucleic Acids Res. 1994 Jun 25;22(12):2370–2374. doi: 10.1093/nar/22.12.2370. [DOI] [PMC free article] [PubMed] [Google Scholar]
  3. Bucheton A., Paro R., Sang H. M., Pelisson A., Finnegan D. J. The molecular basis of I-R hybrid dysgenesis in Drosophila melanogaster: identification, cloning, and properties of the I factor. Cell. 1984 Aug;38(1):153–163. doi: 10.1016/0092-8674(84)90536-1. [DOI] [PubMed] [Google Scholar]
  4. Busseau I., Chaboissier M. C., Pélisson A., Bucheton A. I factors in Drosophila melanogaster: transposition under control. Genetica. 1994;93(1-3):101–116. doi: 10.1007/BF01435243. [DOI] [PubMed] [Google Scholar]
  5. Busseau I., Malinsky S., Balakireva M., Chaboissier M. C., Teninges D., Bucheton A. A genetically marked I element in Drosophila melanogaster can be mobilized when ORF2 is provided in trans. Genetics. 1998 Jan;148(1):267–275. doi: 10.1093/genetics/148.1.267. [DOI] [PMC free article] [PubMed] [Google Scholar]
  6. Chaboissier M. C., Bornecque C., Busseau I., Bucheton A. A genetically tagged, defective I element can be complemented by actively transposing I factors in the germline of I-R dysgenic females in Drosophila melanogaster. Mol Gen Genet. 1995 Aug 30;248(4):434–438. doi: 10.1007/BF02191643. [DOI] [PubMed] [Google Scholar]
  7. Chaboissier M. C., Bucheton A., Finnegan D. J. Copy number control of a transposable element, the I factor, a LINE-like element in Drosophila. Proc Natl Acad Sci U S A. 1998 Sep 29;95(20):11781–11785. doi: 10.1073/pnas.95.20.11781. [DOI] [PMC free article] [PubMed] [Google Scholar]
  8. Chaboissier M. C., Busseau I., Prosser J., Finnegan D. J., Bucheton A. Identification of a potential RNA intermediate for transposition of the LINE-like element I factor in Drosophila melanogaster. EMBO J. 1990 Nov;9(11):3557–3563. doi: 10.1002/j.1460-2075.1990.tb07566.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
  9. Fawcett D. H., Lister C. K., Kellett E., Finnegan D. J. Transposable elements controlling I-R hybrid dysgenesis in D. melanogaster are similar to mammalian LINEs. Cell. 1986 Dec 26;47(6):1007–1015. doi: 10.1016/0092-8674(86)90815-9. [DOI] [PubMed] [Google Scholar]
  10. Jensen S., Cavarec L., Dhellin O., Heidmann T. Retrotransposition of a marked Drosophila line-like I element in cells in culture. Nucleic Acids Res. 1994 Apr 25;22(8):1484–1488. doi: 10.1093/nar/22.8.1484. [DOI] [PMC free article] [PubMed] [Google Scholar]
  11. Jensen S., Cavarec L., Gassama M. P., Heidmann T. Defective I elements introduced into Drosophila as transgenes can regulate reactivity and prevent I-R hybrid dysgenesis. Mol Gen Genet. 1995 Aug 30;248(4):381–390. doi: 10.1007/BF02191637. [DOI] [PubMed] [Google Scholar]
  12. Jensen S., Gassama M. P., Heidmann T. Cosuppression of I transposon activity in Drosophila by I-containing sense and antisense transgenes. Genetics. 1999 Dec;153(4):1767–1774. doi: 10.1093/genetics/153.4.1767. [DOI] [PMC free article] [PubMed] [Google Scholar]
  13. Jensen S., Gassama M. P., Heidmann T. Taming of transposable elements by homology-dependent gene silencing. Nat Genet. 1999 Feb;21(2):209–212. doi: 10.1038/5997. [DOI] [PubMed] [Google Scholar]
  14. Kennerdell J. R., Carthew R. W. Use of dsRNA-mediated genetic interference to demonstrate that frizzled and frizzled 2 act in the wingless pathway. Cell. 1998 Dec 23;95(7):1017–1026. doi: 10.1016/s0092-8674(00)81725-0. [DOI] [PubMed] [Google Scholar]
  15. 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]
  16. Lachaume P., Bouhidel K., Mesure M., Pinon H. Spatial and temporal expression of the I factor during oogenesis in Drosophila melanogaster. Development. 1992 Jul;115(3):729–735. doi: 10.1242/dev.115.3.729. [DOI] [PubMed] [Google Scholar]
  17. Lachaume P., Pinon H. Germ-line expression of the I factor, a functional LINE from the fruit fly Drosophila melanogaster, is positively regulated by reactivity, a peculiar cellular state. Mol Gen Genet. 1993 Aug;240(2):277–285. doi: 10.1007/BF00277067. [DOI] [PubMed] [Google Scholar]
  18. Pal-Bhadra M., Bhadra U., Birchler J. A. Cosuppression in Drosophila: gene silencing of Alcohol dehydrogenase by white-Adh transgenes is Polycomb dependent. Cell. 1997 Aug 8;90(3):479–490. doi: 10.1016/s0092-8674(00)80508-5. [DOI] [PubMed] [Google Scholar]
  19. Pal-Bhadra M., Bhadra U., Birchler J. A. Cosuppression of nonhomologous transgenes in Drosophila involves mutually related endogenous sequences. Cell. 1999 Oct 1;99(1):35–46. doi: 10.1016/s0092-8674(00)80060-4. [DOI] [PubMed] [Google Scholar]
  20. Pritchard M. A., Dura J. M., Pélisson A., Bucheton A., Finnegan D. J. A cloned I-factor is fully functional in Drosophila melanogaster. Mol Gen Genet. 1988 Nov;214(3):533–540. doi: 10.1007/BF00330491. [DOI] [PubMed] [Google Scholar]
  21. 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]
  22. Tuschl T., Zamore P. D., Lehmann R., Bartel D. P., Sharp P. A. Targeted mRNA degradation by double-stranded RNA in vitro. Genes Dev. 1999 Dec 15;13(24):3191–3197. doi: 10.1101/gad.13.24.3191. [DOI] [PMC free article] [PubMed] [Google Scholar]

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