Abstract
Retroviral long terminal repeats (LTRs) contain elements responsible for the control of proviral transcription and gene expression. Molecular clones of the LTR region of a number of avian retroviruses have been isolated, and DNA sequence analysis of these clones reveals the existence of a related, but heterogeneous, family of LTRs. To examine the functional significance of the observed sequence differences, we have directly tested the abilities of several different avian retrovirus LTRs to act as promoters and enhancers of mRNA transcription. Our results indicate that large differences in LTR transcriptional activity exist and that these differences in gene expression directly correlate with LTR enhancer activity. In particular, we show that the LTR of Fujinami sarcoma virus is intermediate in both transcriptional and enhancer activity when compared with the very active LTRs of the exogenous viruses RAV-2 and Schmidt-Ruppin B and the much less active LTRs of the endogenous virus RAV-0 and its provirus ev-2. These results suggest that LTR enhancer activity may be the primary determinant of avian retroviral LTR transcriptional activity and, hence, oncogenic potential.
Full text
PDF






Images in this article
Selected References
These references are in PubMed. This may not be the complete list of references from this article.
- Banerji J., Olson L., Schaffner W. A lymphocyte-specific cellular enhancer is located downstream of the joining region in immunoglobulin heavy chain genes. Cell. 1983 Jul;33(3):729–740. doi: 10.1016/0092-8674(83)90015-6. [DOI] [PubMed] [Google Scholar]
- Banerji J., Rusconi S., Schaffner W. Expression of a beta-globin gene is enhanced by remote SV40 DNA sequences. Cell. 1981 Dec;27(2 Pt 1):299–308. doi: 10.1016/0092-8674(81)90413-x. [DOI] [PubMed] [Google Scholar]
- Berg P. E., Yu J. K., Popovic Z., Schumperli D., Johansen H., Rosenberg M., Anderson W. F. Differential activation of the mouse beta-globin promoter by enhancers. Mol Cell Biol. 1983 Jul;3(7):1246–1254. doi: 10.1128/mcb.3.7.1246. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Bizub D., Katz R. A., Skalka A. M. Nucleotide sequence of noncoding regions in Rous-associated virus-2: comparisons delineate conserved regions important in replication and oncogenesis. J Virol. 1984 Feb;49(2):557–565. doi: 10.1128/jvi.49.2.557-565.1984. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Cullen B. R., Lomedico P. T., Ju G. Transcriptional interference in avian retroviruses--implications for the promoter insertion model of leukaemogenesis. Nature. 1984 Jan 19;307(5948):241–245. doi: 10.1038/307241a0. [DOI] [PubMed] [Google Scholar]
- Cullen B. R., Skalka A. M., Ju G. Endogenous avian retroviruses contain deficient promoter and leader sequences. Proc Natl Acad Sci U S A. 1983 May;80(10):2946–2950. doi: 10.1073/pnas.80.10.2946. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Gillies S. D., Morrison S. L., Oi V. T., Tonegawa S. A tissue-specific transcription enhancer element is located in the major intron of a rearranged immunoglobulin heavy chain gene. Cell. 1983 Jul;33(3):717–728. doi: 10.1016/0092-8674(83)90014-4. [DOI] [PubMed] [Google Scholar]
- Hayward W. S. Size and genetic content of viral RNAs in avian oncovirus-infected cells. J Virol. 1977 Oct;24(1):47–63. doi: 10.1128/jvi.24.1.47-63.1977. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Hishinuma F., DeBona P. J., Astrin S., Skalka A. M. Nucleotide sequence of acceptor site and termini of integrated avian endogenous provirus ev1: integration creates a 6 bp repeat of host DNA. Cell. 1981 Jan;23(1):155–164. doi: 10.1016/0092-8674(81)90280-4. [DOI] [PubMed] [Google Scholar]
- Hughes S. H., Shank P. R., Spector D. H., Kung H. J., Bishop J. M., Varmus H. E., Vogt P. K., Breitman M. L. Proviruses of avian sarcoma virus are terminally redundant, co-extensive with unintegrated linear DNA and integrated at many sites. Cell. 1978 Dec;15(4):1397–1410. doi: 10.1016/0092-8674(78)90064-8. [DOI] [PubMed] [Google Scholar]
- Khoury G., Gruss P. Enhancer elements. Cell. 1983 Jun;33(2):313–314. doi: 10.1016/0092-8674(83)90410-5. [DOI] [PubMed] [Google Scholar]
- Laimins L. A., Khoury G., Gorman C., Howard B., Gruss P. Host-specific activation of transcription by tandem repeats from simian virus 40 and Moloney murine sarcoma virus. Proc Natl Acad Sci U S A. 1982 Nov;79(21):6453–6457. doi: 10.1073/pnas.79.21.6453. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Lenz J., Celander D., Crowther R. L., Patarca R., Perkins D. W., Haseltine W. A. Determination of the leukaemogenicity of a murine retrovirus by sequences within the long terminal repeat. 1984 Mar 29-Apr 4Nature. 308(5958):467–470. doi: 10.1038/308467a0. [DOI] [PubMed] [Google Scholar]
- Lomedico P. T. Use of recombinant DNA technology to program eukaryotic cells to synthesize rat proinsulin: a rapid expression assay for cloned genes. Proc Natl Acad Sci U S A. 1982 Oct;79(19):5798–5802. doi: 10.1073/pnas.79.19.5798. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Luciw P. A., Bishop J. M., Varmus H. E., Capecchi M. R. Location and function of retroviral and SV40 sequences that enhance biochemical transformation after microinjection of DNA. Cell. 1983 Jul;33(3):705–716. doi: 10.1016/0092-8674(83)90013-2. [DOI] [PubMed] [Google Scholar]
- Robinson H. L., Blais B. M., Tsichlis P. N., Coffin J. M. At least two regions of the viral genome determine the oncogenic potential of avian leukosis viruses. Proc Natl Acad Sci U S A. 1982 Feb;79(4):1225–1229. doi: 10.1073/pnas.79.4.1225. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Scholl D. R., Kahn S., Malavarca R., Astrin S., Skalka A. M. Nucleotide sequence of the long terminal repeat and flanking cellular sequences of avian endogenous retrovirus ev-2: variation in Rous-associated virus-0 expression cannot be explained by differences in primary sequence. J Virol. 1983 Feb;45(2):868–871. doi: 10.1128/jvi.45.2.868-871.1983. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Schwartz D. E., Tizard R., Gilbert W. Nucleotide sequence of Rous sarcoma virus. Cell. 1983 Mar;32(3):853–869. doi: 10.1016/0092-8674(83)90071-5. [DOI] [PubMed] [Google Scholar]
- Shank P. R., Hughes S. H., Kung H. J., Majors J. E., Quintrell N., Guntaka R. V., Bishop J. M., Varmus H. E. Mapping unintegrated avian sarcoma virus DNA: termini of linear DNA bear 300 nucleotides present once or twice in two species of circular DNA. Cell. 1978 Dec;15(4):1383–1395. doi: 10.1016/0092-8674(78)90063-6. [DOI] [PubMed] [Google Scholar]
- Shibuya M., Hanafusa H., Balduzzi P. C. Cellular sequences related to three new onc genes of avian sarcoma virus (fps, yes, and ros) and their expression in normal and transformed cells. J Virol. 1982 Apr;42(1):143–152. doi: 10.1128/jvi.42.1.143-152.1982. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Shibuya M., Hanafusa H. Nucleotide sequence of Fujinami sarcoma virus: evolutionary relationship of its transforming gene with transforming genes of other sarcoma viruses. Cell. 1982 Oct;30(3):787–795. doi: 10.1016/0092-8674(82)90283-5. [DOI] [PubMed] [Google Scholar]
- Shibuya M., Wang L. H., Hanafusa H. Molecular cloning of the Fujinami sarcoma virus genome and its comparison with sequences of other related transforming viruses. J Virol. 1982 Jun;42(3):1007–1016. doi: 10.1128/jvi.42.3.1007-1016.1982. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Stacey D. W., Allfrey V. G., Hanafusa H. Microinjection analysis of envelope-glycoprotein messenger activities of avian leukosis viral RNAs. Proc Natl Acad Sci U S A. 1977 Apr;74(4):1614–1618. doi: 10.1073/pnas.74.4.1614. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Thirion J. P., Banville D., Noel H. Galactokinase mutants of Chinese hamster somatic cells resistant to 2-deoxygalactose. Genetics. 1976 May;83(1):137–147. doi: 10.1093/genetics/83.1.137. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Treisman R., Green M. R., Maniatis T. cis and trans activation of globin gene transcription in transient assays. Proc Natl Acad Sci U S A. 1983 Dec;80(24):7428–7432. doi: 10.1073/pnas.80.24.7428. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Tsichlis P. N., Donehower L., Hager G., Zeller N., Malavarca R., Astrin S., Skalka A. M. Sequence comparison in the crossover region of an oncogenic avian retrovirus recombinant and its nononcogenic parent: genetic regions that control growth rate and oncogenic potential. Mol Cell Biol. 1982 Nov;2(11):1331–1338. doi: 10.1128/mcb.2.11.1331. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Walker M. D., Edlund T., Boulet A. M., Rutter W. J. Cell-specific expression controlled by the 5'-flanking region of insulin and chymotrypsin genes. Nature. 1983 Dec 8;306(5943):557–561. doi: 10.1038/306557a0. [DOI] [PubMed] [Google Scholar]
- Weber F., de Villiers J., Schaffner W. An SV40 "enhancer trap" incorporates exogenous enhancers or generates enhancers from its own sequences. Cell. 1984 Apr;36(4):983–992. doi: 10.1016/0092-8674(84)90048-5. [DOI] [PubMed] [Google Scholar]
- Weiher H., Botchan M. R. An enhancer sequence from bovine papilloma virus DNA consists of two essential regions. Nucleic Acids Res. 1984 Mar 26;12(6):2901–2916. doi: 10.1093/nar/12.6.2901. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Weiher H., König M., Gruss P. Multiple point mutations affecting the simian virus 40 enhancer. Science. 1983 Feb 11;219(4585):626–631. doi: 10.1126/science.6297005. [DOI] [PubMed] [Google Scholar]
- Wigler M., Pellicer A., Silverstein S., Axel R., Urlaub G., Chasin L. DNA-mediated transfer of the adenine phosphoribosyltransferase locus into mammalian cells. Proc Natl Acad Sci U S A. 1979 Mar;76(3):1373–1376. doi: 10.1073/pnas.76.3.1373. [DOI] [PMC free article] [PubMed] [Google Scholar]
- de Villiers J., Olson L., Tyndall C., Schaffner W. Transcriptional 'enhancers' from SV40 and polyoma virus show a cell type preference. Nucleic Acids Res. 1982 Dec 20;10(24):7965–7976. doi: 10.1093/nar/10.24.7965. [DOI] [PMC free article] [PubMed] [Google Scholar]