Abstract
The structure and transcriptional regulation of the 1.8 variant cell surface glycoprotein (VSG) gene expression site located on a 430-kilobase (kb) chromosome was examined in a 430-kb-chromosome-specific library. Using 32P-labeled nascent transcripts generated by nuclear run-on, we selected recombinant clones derived from the 430-kb chromosome which were coordinately activated with the 1.8 VSG gene. The results show that a repetitive region with a minimum size of 27 kb is coordinately activated with the 1.8 VSG gene. As with the 1.8 VSG gene, transcription is by RNA polymerases that are insensitive to the drug alpha-amanitin at concentrations up to 1 mg/ml. Transcription results in the generation of several stable variant-specific mRNAs. These mRNAs most likely belong to a family of repetitive expression-site-associated genes.
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.
- Auffray C., Rougeon F. Purification of mouse immunoglobulin heavy-chain messenger RNAs from total myeloma tumor RNA. Eur J Biochem. 1980 Jun;107(2):303–314. doi: 10.1111/j.1432-1033.1980.tb06030.x. [DOI] [PubMed] [Google Scholar]
- Bernards A., De Lange T., Michels P. A., Liu A. Y., Huisman M. J., Borst P. Two modes of activation of a single surface antigen gene of Trypanosoma brucei. Cell. 1984 Jan;36(1):163–170. doi: 10.1016/0092-8674(84)90085-0. [DOI] [PubMed] [Google Scholar]
- Bernards A., Van der Ploeg L. H., Frasch A. C., Borst P., Boothroyd J. C., Coleman S., Cross G. A. Activation of trypanosome surface glycoprotein genes involves a duplication-transposition leading to an altered 3' end. Cell. 1981 Dec;27(3 Pt 2):497–505. doi: 10.1016/0092-8674(81)90391-3. [DOI] [PubMed] [Google Scholar]
- Birnboim H. C., Doly J. A rapid alkaline extraction procedure for screening recombinant plasmid DNA. Nucleic Acids Res. 1979 Nov 24;7(6):1513–1523. doi: 10.1093/nar/7.6.1513. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Borst P. Discontinuous transcription and antigenic variation in trypanosomes. Annu Rev Biochem. 1986;55:701–732. doi: 10.1146/annurev.bi.55.070186.003413. [DOI] [PubMed] [Google Scholar]
- Borst P., Greaves D. R. Programmed gene rearrangements altering gene expression. Science. 1987 Feb 6;235(4789):658–667. doi: 10.1126/science.3544215. [DOI] [PubMed] [Google Scholar]
- Cross G. A. Identification, purification and properties of clone-specific glycoprotein antigens constituting the surface coat of Trypanosoma brucei. Parasitology. 1975 Dec;71(3):393–417. doi: 10.1017/s003118200004717x. [DOI] [PubMed] [Google Scholar]
- Cully D. F., Ip H. S., Cross G. A. Coordinate transcription of variant surface glycoprotein genes and an expression site associated gene family in Trypanosoma brucei. Cell. 1985 Aug;42(1):173–182. doi: 10.1016/s0092-8674(85)80113-6. [DOI] [PubMed] [Google Scholar]
- De Lange T., Borst P. Genomic environment of the expression-linked extra copies of genes for surface antigens of Trypanosoma brucei resembles the end of a chromosome. Nature. 1982 Sep 30;299(5882):451–453. doi: 10.1038/299451a0. [DOI] [PubMed] [Google Scholar]
- De Lange T., Kooter J. M., Michels P. A., Borst P. Telomere conversion in trypanosomes. Nucleic Acids Res. 1983 Dec 10;11(23):8149–8165. doi: 10.1093/nar/11.23.8149. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Fairlamb A. H., Weislogel P. O., Hoeijmakers J. H., Borst P. Isolation and characterization of kinetoplast DNA from bloodstream form of Trypanosoma brucei. J Cell Biol. 1978 Feb;76(2):293–309. doi: 10.1083/jcb.76.2.293. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Hoeijmakers J. H., Frasch A. C., Bernards A., Borst P., Cross G. A. Novel expression-linked copies of the genes for variant surface antigens in trypanosomes. Nature. 1980 Mar 6;284(5751):78–80. doi: 10.1038/284078a0. [DOI] [PubMed] [Google Scholar]
- Johnson P. J., Kooter J. M., Borst P. Inactivation of transcription by UV irradiation of T. brucei provides evidence for a multicistronic transcription unit including a VSG gene. Cell. 1987 Oct 23;51(2):273–281. doi: 10.1016/0092-8674(87)90154-1. [DOI] [PubMed] [Google Scholar]
- Kooter J. M., Borst P. Alpha-amanitin-insensitive transcription of variant surface glycoprotein genes provides further evidence for discontinuous transcription in trypanosomes. Nucleic Acids Res. 1984 Dec 21;12(24):9457–9472. doi: 10.1093/nar/12.24.9457. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Kooter J. M., van der Spek H. J., Wagter R., d'Oliveira C. E., van der Hoeven F., Johnson P. J., Borst P. The anatomy and transcription of a telomeric expression site for variant-specific surface antigens in T. brucei. Cell. 1987 Oct 23;51(2):261–272. doi: 10.1016/0092-8674(87)90153-x. [DOI] [PubMed] [Google Scholar]
- Michels P. A., Liu A. Y., Bernards A., Sloof P., Van der Bijl M. M., Schinkel A. H., Menke H. H., Borst P., Veeneman G. H., Tromp M. C. Activation of the genes for variant surface glycoproteins 117 and 118 in Trypanosoma brucei. J Mol Biol. 1983 Jun 5;166(4):537–556. doi: 10.1016/s0022-2836(83)80283-6. [DOI] [PubMed] [Google Scholar]
- Michels P. A., Van der Ploeg L. H., Liu A. Y., Borst P. The inactivation and reactivation of an expression-linked gene copy for a variant surface glycoprotein in Trypanosoma brucei. EMBO J. 1984 Jun;3(6):1345–1351. doi: 10.1002/j.1460-2075.1984.tb01975.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Myler P., Nelson R. G., Agabian N., Stuart K. Two mechanisms of expression of a predominant variant antigen gene of Trypanosoma brucei. Nature. 1984 May 17;309(5965):282–284. doi: 10.1038/309282a0. [DOI] [PubMed] [Google Scholar]
- Pays E., Delauw M. F., Van Assel S., Laurent M., Vervoort T., Van Meirvenne N., Steinert M. Modifications of a Trypanosoma b. brucei antigen gene repertoire by different DNA recombinational mechanisms. Cell. 1983 Dec;35(3 Pt 2):721–731. doi: 10.1016/0092-8674(83)90105-8. [DOI] [PubMed] [Google Scholar]
- Pays E., Guyaux M., Aerts D., Van Meirvenne N., Steinert M. Telomeric reciprocal recombination as a possible mechanism for antigenic variation in trypanosomes. Nature. 1985 Aug 8;316(6028):562–564. doi: 10.1038/316562a0. [DOI] [PubMed] [Google Scholar]
- Pays E., Van Assel S., Laurent M., Dero B., Michiels F., Kronenberger P., Matthyssens G., Van Meirvenne N., Le Ray D., Steinert M. At least two transposed sequences are associated in the expression site of a surface antigen gene in different trypanosome clones. Cell. 1983 Sep;34(2):359–369. doi: 10.1016/0092-8674(83)90370-7. [DOI] [PubMed] [Google Scholar]
- Rothwell V., Aline R., Jr, Parsons M., Agabian N., Stuart K. Expression of a minichromosomal variant surface glycoprotein gene in Trypanosoma brucei. Nature. 1985 Feb 14;313(6003):595–597. doi: 10.1038/313595a0. [DOI] [PubMed] [Google Scholar]
- Schwartz D. C., Cantor C. R. Separation of yeast chromosome-sized DNAs by pulsed field gradient gel electrophoresis. Cell. 1984 May;37(1):67–75. doi: 10.1016/0092-8674(84)90301-5. [DOI] [PubMed] [Google Scholar]
- Shea C., Glass D. J., Parangi S., Van der Ploeg L. H. Variant surface glycoprotein gene expression site switches in Trypanosoma brucei. J Biol Chem. 1986 May 5;261(13):6056–6063. [PubMed] [Google Scholar]
- Shea C., Lee M. G., Van der Ploeg L. H. VSG gene 118 is transcribed from a cotransposed pol I-like promoter. Cell. 1987 Aug 14;50(4):603–612. doi: 10.1016/0092-8674(87)90033-x. [DOI] [PubMed] [Google Scholar]
- Van der Ploeg L. H., Bernards A., Rijsewijk F. A., Borst P. Characterization of the DNA duplication-transposition that controls the expression of two genes for variant surface glycoproteins in Trypanosoma brucei. Nucleic Acids Res. 1982 Jan 22;10(2):593–609. doi: 10.1093/nar/10.2.593. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Van der Ploeg L. H., Cornelissen A. W., Michels P. A., Borst P. Chromosome rearrangements in Trypanosoma brucei. Cell. 1984 Nov;39(1):213–221. doi: 10.1016/0092-8674(84)90207-1. [DOI] [PubMed] [Google Scholar]
- Van der Ploeg L. H., Cornelissen A. W. The contribution of chromosomal translocations to antigenic variation in Trypanosoma brucei. Philos Trans R Soc Lond B Biol Sci. 1984 Nov 13;307(1131):13–26. doi: 10.1098/rstb.1984.0105. [DOI] [PubMed] [Google Scholar]
- Van der Ploeg L. H., Schwartz D. C., Cantor C. R., Borst P. Antigenic variation in Trypanosoma brucei analyzed by electrophoretic separation of chromosome-sized DNA molecules. Cell. 1984 May;37(1):77–84. doi: 10.1016/0092-8674(84)90302-7. [DOI] [PubMed] [Google Scholar]
- Van der Ploeg L. H., Valerio D., De Lange T., Bernards A., Borst P., Grosveld F. G. An analysis of cosmid clones of nuclear DNA from Trypanosoma brucei shows that the genes for variant surface glycoproteins are clustered in the genome. Nucleic Acids Res. 1982 Oct 11;10(19):5905–5923. doi: 10.1093/nar/10.19.5905. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Vickerman K. Antigenic variation in trypanosomes. Nature. 1978 Jun 22;273(5664):613–617. doi: 10.1038/273613a0. [DOI] [PubMed] [Google Scholar]
- Vickerman K. On the surface coat and flagellar adhesion in trypanosomes. J Cell Sci. 1969 Jul;5(1):163–193. doi: 10.1242/jcs.5.1.163. [DOI] [PubMed] [Google Scholar]
- Williams R. O., Young J. R., Majiwa P. A., Doyle J. J., Shapiro S. Z. Contextural genomic rearrangements of variable-antigen genes in Trypanosoma brucei. Cold Spring Harb Symp Quant Biol. 1981;45(Pt 2):945–949. doi: 10.1101/sqb.1981.045.01.111. [DOI] [PubMed] [Google Scholar]
- Williams R. O., Young J. R., Majiwa P. A. Genomic environment of T. brucei VSG genes: presence of a minichromosome. Nature. 1982 Sep 30;299(5882):417–421. doi: 10.1038/299417a0. [DOI] [PubMed] [Google Scholar]