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. 1987 Sep 25;15(18):7357–7368. doi: 10.1093/nar/15.18.7357

Transcription of the intergenic regions of the tubulin gene cluster of Trypanosoma brucei: evidence for a polycistronic transcription unit in a eukaryote.

M A Imboden 1, P W Laird 1, M Affolter 1, T Seebeck 1
PMCID: PMC306253  PMID: 3658696

Abstract

The tubulin genes of T. brucei are clustered in a tightly packed array of alternating alpha- and beta-genes. The steady state mRNA contains one abundant mRNA species each for alpha- and beta-tubulin, both carrying the identical 35 nt mini-exon sequence at their 5'-ends. We have used in vitro run-on transcription assays to investigate the mechanism of tubulin gene transcription in T. brucei. Our results show that the regions between the individual tubulin genes are transcribed at the same rate as are the genes themselves. On the other hand, transcripts containing the intergenic regions could not be detected by Northern analysis or in vivo labelling experiments. We conclude that putative transcripts from the intergenic regions have a half-life of less than one minute. These results suggest that the tubulin gene cluster is transcribed as a single contiguous transcription unit yielding a primary transcript which is rapidly processed into individual mRNAs by the polyadenylation and mini-exon trans splicing machineries.

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Selected References

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

  1. Black D. L., Chabot B., Steitz J. A. U2 as well as U1 small nuclear ribonucleoproteins are involved in premessenger RNA splicing. Cell. 1985 Oct;42(3):737–750. doi: 10.1016/0092-8674(85)90270-3. [DOI] [PubMed] [Google Scholar]
  2. 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]
  3. Brun R., Schönenberger Cultivation and in vitro cloning or procyclic culture forms of Trypanosoma brucei in a semi-defined medium. Short communication. Acta Trop. 1979 Sep;36(3):289–292. [PubMed] [Google Scholar]
  4. Campbell D. A., Thornton D. A., Boothroyd J. C. Apparent discontinuous transcription of Trypanosoma brucei variant surface antigen genes. 1984 Sep 27-Oct 3Nature. 311(5984):350–355. doi: 10.1038/311350a0. [DOI] [PMC free article] [PubMed] [Google Scholar]
  5. Cornelissen A. W., Verspieren M. P., Toulmé J. J., Swinkels B. W., Borst P. The common 5' terminal sequence on trypanosome mRNAs: a target for anti-messenger oligodeoxynucleotides. Nucleic Acids Res. 1986 Jul 25;14(14):5605–5614. doi: 10.1093/nar/14.14.5605. [DOI] [PMC free article] [PubMed] [Google Scholar]
  6. 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]
  7. Darnell J. E., Jr Variety in the level of gene control in eukaryotic cells. Nature. 1982 Jun 3;297(5865):365–371. doi: 10.1038/297365a0. [DOI] [PubMed] [Google Scholar]
  8. De Lange T., Liu A. Y., Van der Ploeg L. H., Borst P., Tromp M. C., Van Boom J. H. Tandem repetition of the 5' mini-exon of variant surface glycoprotein genes: a multiple promoter for VSG gene transcription? Cell. 1983 Oct;34(3):891–900. doi: 10.1016/0092-8674(83)90546-9. [DOI] [PubMed] [Google Scholar]
  9. De Lange T., Michels P. A., Veerman H. J., Cornelissen A. W., Borst P. Many trypanosome messenger RNAs share a common 5' terminal sequence. Nucleic Acids Res. 1984 May 11;12(9):3777–3790. doi: 10.1093/nar/12.9.3777. [DOI] [PMC free article] [PubMed] [Google Scholar]
  10. Dente L., Cesareni G., Cortese R. pEMBL: a new family of single stranded plasmids. Nucleic Acids Res. 1983 Mar 25;11(6):1645–1655. doi: 10.1093/nar/11.6.1645. [DOI] [PMC free article] [PubMed] [Google Scholar]
  11. Ehlers B., Czichos J., Overath P. RNA turnover in Trypanosoma brucei. Mol Cell Biol. 1987 Mar;7(3):1242–1249. doi: 10.1128/mcb.7.3.1242. [DOI] [PMC free article] [PubMed] [Google Scholar]
  12. Glass D. J., Polvere R. I., Van der Ploeg L. H. Conserved sequences and transcription of the hsp70 gene family in Trypanosoma brucei. Mol Cell Biol. 1986 Dec;6(12):4657–4666. doi: 10.1128/mcb.6.12.4657. [DOI] [PMC free article] [PubMed] [Google Scholar]
  13. Gonzalez A., Lerner T. J., Huecas M., Sosa-Pineda B., Nogueira N., Lizardi P. M. Apparent generation of a segmented mRNA from two separate tandem gene families in Trypanosoma cruzi. Nucleic Acids Res. 1985 Aug 26;13(16):5789–5804. doi: 10.1093/nar/13.16.5789. [DOI] [PMC free article] [PubMed] [Google Scholar]
  14. Hall A., Marshall C. J., Spurr N. K., Weiss R. A. Identification of transforming gene in two human sarcoma cell lines as a new member of the ras gene family located on chromosome 1. Nature. 1983 Jun 2;303(5916):396–400. doi: 10.1038/303396a0. [DOI] [PubMed] [Google Scholar]
  15. Harding J. D., Przybyla A. E., MacDonald R. J., Pictet R. L., Rutter W. J. Effects of dexamethasone and 5-bromodeoxyuridine on the synthesis of amylase mRNA during pancreatic development in vitro. J Biol Chem. 1978 Oct 25;253(20):7531–7537. [PubMed] [Google Scholar]
  16. Hoeijmakers J. H., Borst P., van den Burg J., Weissmann C., Cross G. A. The isolation of plasmids containing DNA complementary to messenger RNA for variant surface glycoproteins of Trypanosoma brucei. Gene. 1980 Mar;8(4):391–417. doi: 10.1016/0378-1119(80)90043-8. [DOI] [PubMed] [Google Scholar]
  17. Humphreys G. O., Willshaw G. A., Anderson E. S. A simple method for the preparation of large quantities of pure plasmid DNA. Biochim Biophys Acta. 1975 Apr 2;383(4):457–463. doi: 10.1016/0005-2787(75)90318-4. [DOI] [PubMed] [Google Scholar]
  18. Hunt C., Morimoto R. I. Conserved features of eukaryotic hsp70 genes revealed by comparison with the nucleotide sequence of human hsp70. Proc Natl Acad Sci U S A. 1985 Oct;82(19):6455–6459. doi: 10.1073/pnas.82.19.6455. [DOI] [PMC free article] [PubMed] [Google Scholar]
  19. Imboden M., Blum B., DeLange T., Braun R., Seebeck T. Tubulin mRNAs of Trypanosoma brucei. J Mol Biol. 1986 Apr 5;188(3):393–402. doi: 10.1016/0022-2836(86)90163-4. [DOI] [PubMed] [Google Scholar]
  20. Kimmel B. E., Samson S., Wu J., Hirschberg R., Yarbrough L. R. Tubulin genes of the African trypanosome Trypanosoma brucei rhodesiense:nucleotide sequence of a 3.7-kb fragment containing genes for alpha and beta tubulins. Gene. 1985;35(3):237–248. doi: 10.1016/0378-1119(85)90002-2. [DOI] [PubMed] [Google Scholar]
  21. 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]
  22. Kooter J. M., De Lange T., Borst P. Discontinuous synthesis of mRNA in trypanosomes. EMBO J. 1984 Oct;3(10):2387–2392. doi: 10.1002/j.1460-2075.1984.tb02144.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
  23. Laird P. W., Zomerdijk J. C., de Korte D., Borst P. In vivo labelling of intermediates in the discontinuous synthesis of mRNAs in Trypanosoma brucei. EMBO J. 1987 Apr;6(4):1055–1062. doi: 10.1002/j.1460-2075.1987.tb04858.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
  24. Mead D. A., Skorupa E. S., Kemper B. Single stranded DNA SP6 promoter plasmids for engineering mutant RNAs and proteins: synthesis of a 'stretched' preproparathyroid hormone. Nucleic Acids Res. 1985 Feb 25;13(4):1103–1118. doi: 10.1093/nar/13.4.1103. [DOI] [PMC free article] [PubMed] [Google Scholar]
  25. Michiels F., Matthyssens G., Kronenberger P., Pays E., Dero B., Van Assel S., Darville M., Carvador A., Steinert M., Hamers R. Gene activation and re-expression of a Trypanosoma brucei variant surface glycoprotein. EMBO J. 1983;2(7):1185–1192. doi: 10.1002/j.1460-2075.1983.tb01565.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
  26. Milhausen M., Nelson R. G., Sather S., Selkirk M., Agabian N. Identification of a small RNA containing the trypanosome spliced leader: a donor of shared 5' sequences of trypanosomatid mRNAs? Cell. 1984 Oct;38(3):721–729. doi: 10.1016/0092-8674(84)90267-8. [DOI] [PMC free article] [PubMed] [Google Scholar]
  27. Mount S. M. A catalogue of splice junction sequences. Nucleic Acids Res. 1982 Jan 22;10(2):459–472. doi: 10.1093/nar/10.2.459. [DOI] [PMC free article] [PubMed] [Google Scholar]
  28. Murphy W. J., Watkins K. P., Agabian N. Identification of a novel Y branch structure as an intermediate in trypanosome mRNA processing: evidence for trans splicing. Cell. 1986 Nov 21;47(4):517–525. doi: 10.1016/0092-8674(86)90616-1. [DOI] [PubMed] [Google Scholar]
  29. Nelson R. G., Parsons M., Barr P. J., Stuart K., Selkirk M., Agabian N. Sequences homologous to the variant antigen mRNA spliced leader are located in tandem repeats and variable orphons in trypanosoma brucei. Cell. 1983 Oct;34(3):901–909. doi: 10.1016/0092-8674(83)90547-0. [DOI] [PubMed] [Google Scholar]
  30. Osinga K. A., Swinkels B. W., Gibson W. C., Borst P., Veeneman G. H., Van Boom J. H., Michels P. A., Opperdoes F. R. Topogenesis of microbody enzymes: a sequence comparison of the genes for the glycosomal (microbody) and cytosolic phosphoglycerate kinases of Trypanosoma brucei. EMBO J. 1985 Dec 30;4(13B):3811–3817. doi: 10.1002/j.1460-2075.1985.tb04152.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
  31. Parsons M., Nelson R. G., Watkins K. P., Agabian N. Trypanosome mRNAs share a common 5' spliced leader sequence. Cell. 1984 Aug;38(1):309–316. doi: 10.1016/0092-8674(84)90552-X. [DOI] [PMC free article] [PubMed] [Google Scholar]
  32. 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]
  33. Sather S., Agabian N. A 5' spliced leader is added in trans to both alpha- and beta-tubulin transcripts in Trypanosoma brucei. Proc Natl Acad Sci U S A. 1985 Sep;82(17):5695–5699. doi: 10.1073/pnas.82.17.5695. [DOI] [PMC free article] [PubMed] [Google Scholar]
  34. Schibler U., Hagenbüchle O., Wellauer P. K., Pittet A. C. Two promoters of different strengths control the transcription of the mouse alpha-amylase gene Amy-1a in the parotid gland and the liver. Cell. 1983 Jun;33(2):501–508. doi: 10.1016/0092-8674(83)90431-2. [DOI] [PubMed] [Google Scholar]
  35. Seebeck T., Whittaker P. A., Imboden M. A., Hardman N., Braun R. Tubulin genes of Trypanosoma brucei: a tightly clustered family of alternating genes. Proc Natl Acad Sci U S A. 1983 Aug;80(15):4634–4638. doi: 10.1073/pnas.80.15.4634. [DOI] [PMC free article] [PubMed] [Google Scholar]
  36. Shapiro S. Z., Doxsey S. J. Purification of nuclei from a flagellate protozoan, Trypanosoma brucei. Anal Biochem. 1982 Nov 15;127(1):112–115. doi: 10.1016/0003-2697(82)90152-x. [DOI] [PubMed] [Google Scholar]
  37. Sutton R. E., Boothroyd J. C. Evidence for trans splicing in trypanosomes. Cell. 1986 Nov 21;47(4):527–535. doi: 10.1016/0092-8674(86)90617-3. [DOI] [PMC free article] [PubMed] [Google Scholar]
  38. Swinkels B. W., Gibson W. C., Osinga K. A., Kramer R., Veeneman G. H., van Boom J. H., Borst P. Characterization of the gene for the microbody (glycosomal) triosephosphate isomerase of Trypanosoma brucei. EMBO J. 1986 Jun;5(6):1291–1298. doi: 10.1002/j.1460-2075.1986.tb04358.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
  39. Thomas P. S. Hybridization of denatured RNA and small DNA fragments transferred to nitrocellulose. Proc Natl Acad Sci U S A. 1980 Sep;77(9):5201–5205. doi: 10.1073/pnas.77.9.5201. [DOI] [PMC free article] [PubMed] [Google Scholar]
  40. Thomashow L. S., Milhausen M., Rutter W. J., Agabian N. Tubulin genes are tandemly linked and clustered in the genome of trypanosoma brucei. Cell. 1983 Jan;32(1):35–43. doi: 10.1016/0092-8674(83)90494-4. [DOI] [PubMed] [Google Scholar]
  41. Tschudi C., Richards F. F., Ullu E. The U2 RNA analogue of Trypanosoma brucei gambiense: implications for a splicing mechanism in trypanosomes. Nucleic Acids Res. 1986 Nov 25;14(22):8893–8903. doi: 10.1093/nar/14.22.8893. [DOI] [PMC free article] [PubMed] [Google Scholar]
  42. Tullis R. H., Rubin H. Calcium protects DNase I from proteinase K: a new method for the removal of contaminating RNase from DNase I. Anal Biochem. 1980 Sep 1;107(1):260–264. doi: 10.1016/0003-2697(80)90519-9. [DOI] [PubMed] [Google Scholar]
  43. Walder J. A., Eder P. S., Engman D. M., Brentano S. T., Walder R. Y., Knutzon D. S., Dorfman D. M., Donelson J. E. The 35-nucleotide spliced leader sequence is common to all trypanosome messenger RNA's. Science. 1986 Aug 1;233(4763):569–571. doi: 10.1126/science.3523758. [DOI] [PubMed] [Google Scholar]
  44. White T. C., Rudenko G., Borst P. Three small RNAs within the 10 kb trypanosome rRNA transcription unit are analogous to domain VII of other eukaryotic 28S rRNAs. Nucleic Acids Res. 1986 Dec 9;14(23):9471–9489. doi: 10.1093/nar/14.23.9471. [DOI] [PMC free article] [PubMed] [Google Scholar]

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