Skip to main content
PMC home page
Nucleic Acids Research logoLink to Nucleic Acids Research
. 1994 Apr 25;22(8):1359–1364. doi: 10.1093/nar/22.8.1359

Control of polyadenylation and alternative splicing of transcripts from adjacent genes in a procyclin expression site: a dual role for polypyrimidine tracts in trypanosomes?

E Vassella 1, R Braun 1, I Roditi 1
PMCID: PMC307990  PMID: 8190625

Abstract

The procyclin-associated genes (PAGs) of Trypanosoma brucei are located downstream of tandemly repeated procyclin genes and belong to the same alpha-amanitin-resistant polycistronic transcription units. In procyclic form trypanosomes the PAG 1 pre-mRNA is alternatively spliced to give rise to three transcripts of 2.7 kb, 1.8 kb and 1.3 kb. The two larger transcripts contain additional short open reading frames (ORFs) upstream of the major ORF. Trans-splicing to generate these transcripts occurs downstream of three different polypyrimidine tracts. A minor population of procyclin mRNAs is also generated by alternative splicing at a polypyrimidine tract that begins 524 bp upstream of the major splice acceptor site of the procyclin beta-gene. The same polypyrimidine tract is also required for accurate polyadenylation of mRNAs from the upstream procyclin alpha-gene (1). Alternatively polyadenylated forms of PAG 1 mRNAs can also be detected. All polyadenylation sites are found at a similar distance upstream of splice-acceptor sites, in each case with a polypyrimidine tract between them. Our results point to a dual role for polypyrimidine tracts in the maturation of trypanosome mRNAs.

Full text

PDF
1364

Images in this article

1361Image
on p.1361

Selected References

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

  1. Agabian N. Trans splicing of nuclear pre-mRNAs. Cell. 1990 Jun 29;61(7):1157–1160. doi: 10.1016/0092-8674(90)90674-4. [DOI] [PubMed] [Google Scholar]
  2. Alexandre S., Guyaux M., Murphy N. B., Coquelet H., Pays A., Steinert M., Pays E. Putative genes of a variant-specific antigen gene transcription unit in Trypanosoma brucei. Mol Cell Biol. 1988 Jun;8(6):2367–2378. doi: 10.1128/mcb.8.6.2367. [DOI] [PMC free article] [PubMed] [Google Scholar]
  3. Aline R. F., Jr, Scholler J. K., Stuart K. Transcripts from the co-transposed segment of variant surface glycoprotein genes are in Trypanosoma brucei polyribosomes. Mol Biochem Parasitol. 1989 Jan 15;32(2-3):169–178. doi: 10.1016/0166-6851(89)90068-6. [DOI] [PubMed] [Google Scholar]
  4. Berberof M., Pays A., Pays E. A similar gene is shared by both the variant surface glycoprotein and procyclin gene transcription units of Trypanosoma brucei. Mol Cell Biol. 1991 Mar;11(3):1473–1479. doi: 10.1128/mcb.11.3.1473. [DOI] [PMC free article] [PubMed] [Google Scholar]
  5. 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]
  6. Coquelet H., Tebabi P., Pays A., Steinert M., Pays E. Trypanosoma brucei: enrichment by UV of intergenic transcripts from the variable surface glycoprotein gene expression site. Mol Cell Biol. 1989 Sep;9(9):4022–4025. doi: 10.1128/mcb.9.9.4022. [DOI] [PMC free article] [PubMed] [Google Scholar]
  7. Cross G. A. Cellular and genetic aspects of antigenic variation in trypanosomes. Annu Rev Immunol. 1990;8:83–110. doi: 10.1146/annurev.iy.08.040190.000503. [DOI] [PubMed] [Google Scholar]
  8. Cross G. A., Manning J. C. Cultivation of Trypanosoma brucei sspp. in semi-defined and defined media. Parasitology. 1973 Dec;67(3):315–331. doi: 10.1017/s0031182000046540. [DOI] [PubMed] [Google Scholar]
  9. 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]
  10. Florent I. C., Raibaud A., Eisen H. A family of genes related to a new expression site-associated gene in Trypanosoma equiperdum. Mol Cell Biol. 1991 Apr;11(4):2180–2188. doi: 10.1128/mcb.11.4.2180. [DOI] [PMC free article] [PubMed] [Google Scholar]
  11. Frohman M. A., Dush M. K., Martin G. R. Rapid production of full-length cDNAs from rare transcripts: amplification using a single gene-specific oligonucleotide primer. Proc Natl Acad Sci U S A. 1988 Dec;85(23):8998–9002. doi: 10.1073/pnas.85.23.8998. [DOI] [PMC free article] [PubMed] [Google Scholar]
  12. Fütterer J., Hohn T. Role of an upstream open reading frame in the translation of polycistronic mRNAs in plant cells. Nucleic Acids Res. 1992 Aug 11;20(15):3851–3857. doi: 10.1093/nar/20.15.3851. [DOI] [PMC free article] [PubMed] [Google Scholar]
  13. Hehl A., Vassella E., Braun R., Roditi I. A conserved stem-loop structure in the 3' untranslated region of procyclin mRNAs regulates expression in Trypanosoma brucei. Proc Natl Acad Sci U S A. 1994 Jan 4;91(1):370–374. doi: 10.1073/pnas.91.1.370. [DOI] [PMC free article] [PubMed] [Google Scholar]
  14. Hobbs M. R., Boothroyd J. C. An expression-site-associated gene family of trypanosomes is expressed in vivo and shows homology to a variant surface glycoprotein gene. Mol Biochem Parasitol. 1990 Nov;43(1):1–16. doi: 10.1016/0166-6851(90)90125-6. [DOI] [PubMed] [Google Scholar]
  15. Huang J., Van der Ploeg L. H. Requirement of a polypyrimidine tract for trans-splicing in trypanosomes: discriminating the PARP promoter from the immediately adjacent 3' splice acceptor site. EMBO J. 1991 Dec;10(12):3877–3885. doi: 10.1002/j.1460-2075.1991.tb04957.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
  16. 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]
  17. König E., Delius H., Carrington M., Williams R. O., Roditi I. Duplication and transcription of procyclin genes in Trypanosoma brucei. Nucleic Acids Res. 1989 Nov 11;17(21):8727–8739. doi: 10.1093/nar/17.21.8727. [DOI] [PMC free article] [PubMed] [Google Scholar]
  18. LeBowitz J. H., Smith H. Q., Rusche L., Beverley S. M. Coupling of poly(A) site selection and trans-splicing in Leishmania. Genes Dev. 1993 Jun;7(6):996–1007. doi: 10.1101/gad.7.6.996. [DOI] [PubMed] [Google Scholar]
  19. Maniatis T. Mechanisms of alternative pre-mRNA splicing. Science. 1991 Jan 4;251(4989):33–34. doi: 10.1126/science.1824726. [DOI] [PubMed] [Google Scholar]
  20. McKeown M. Alternative mRNA splicing. Annu Rev Cell Biol. 1992;8:133–155. doi: 10.1146/annurev.cb.08.110192.001025. [DOI] [PubMed] [Google Scholar]
  21. Miller E. N., Turner M. J. Analysis of antigenic types appearing in first relapse populations of clones of Trypanosoma brucei. Parasitology. 1981 Feb;82(1):63–80. doi: 10.1017/s0031182000041871. [DOI] [PubMed] [Google Scholar]
  22. Mowatt M. R., Wisdom G. S., Clayton C. E. Variation of tandem repeats in the developmentally regulated procyclic acidic repetitive proteins of Trypanosoma brucei. Mol Cell Biol. 1989 Mar;9(3):1332–1335. doi: 10.1128/mcb.9.3.1332. [DOI] [PMC free article] [PubMed] [Google Scholar]
  23. Mueller P. P., Hinnebusch A. G. Multiple upstream AUG codons mediate translational control of GCN4. Cell. 1986 Apr 25;45(2):201–207. doi: 10.1016/0092-8674(86)90384-3. [DOI] [PubMed] [Google Scholar]
  24. Pays E., Coquelet H., Pays A., Tebabi P., Steinert M. Trypanosoma brucei: posttranscriptional control of the variable surface glycoprotein gene expression site. Mol Cell Biol. 1989 Sep;9(9):4018–4021. doi: 10.1128/mcb.9.9.4018. [DOI] [PMC free article] [PubMed] [Google Scholar]
  25. Pays E., Coquelet H., Tebabi P., Pays A., Jefferies D., Steinert M., Koenig E., Williams R. O., Roditi I. Trypanosoma brucei: constitutive activity of the VSG and procyclin gene promoters. EMBO J. 1990 Oct;9(10):3145–3151. doi: 10.1002/j.1460-2075.1990.tb07512.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
  26. Pays E., Steinert M. Control of antigen gene expression in African trypanosomes. Annu Rev Genet. 1988;22:107–126. doi: 10.1146/annurev.ge.22.120188.000543. [DOI] [PubMed] [Google Scholar]
  27. Pays E., Tebabi P., Pays A., Coquelet H., Revelard P., Salmon D., Steinert M. The genes and transcripts of an antigen gene expression site from T. brucei. Cell. 1989 Jun 2;57(5):835–845. doi: 10.1016/0092-8674(89)90798-8. [DOI] [PubMed] [Google Scholar]
  28. Revelard P., Lips S., Pays E. A gene from the VSG expression site of Trypanosoma brucei encodes a protein with both leucine-rich repeats and a putative zinc finger. Nucleic Acids Res. 1990 Dec 25;18(24):7299–7303. doi: 10.1093/nar/18.24.7299. [DOI] [PMC free article] [PubMed] [Google Scholar]
  29. Richardson J. P., Beecroft R. P., Tolson D. L., Liu M. K., Pearson T. W. Procyclin: an unusual immunodominant glycoprotein surface antigen from the procyclic stage of African trypanosomes. Mol Biochem Parasitol. 1988 Dec;31(3):203–216. doi: 10.1016/0166-6851(88)90150-8. [DOI] [PubMed] [Google Scholar]
  30. Roditi I., Carrington M., Turner M. Expression of a polypeptide containing a dipeptide repeat is confined to the insect stage of Trypanosoma brucei. Nature. 1987 Jan 15;325(6101):272–274. doi: 10.1038/325272a0. [DOI] [PubMed] [Google Scholar]
  31. Roditi I., Schwarz H., Pearson T. W., Beecroft R. P., Liu M. K., Richardson J. P., Bühring H. J., Pleiss J., Bülow R., Williams R. O. Procyclin gene expression and loss of the variant surface glycoprotein during differentiation of Trypanosoma brucei. J Cell Biol. 1989 Feb;108(2):737–746. doi: 10.1083/jcb.108.2.737. [DOI] [PMC free article] [PubMed] [Google Scholar]
  32. Rudenko G., Le Blancq S., Smith J., Lee M. G., Rattray A., Van der Ploeg L. H. Procyclic acidic repetitive protein (PARP) genes located in an unusually small alpha-amanitin-resistant transcription unit: PARP promoter activity assayed by transient DNA transfection of Trypanosoma brucei. Mol Cell Biol. 1990 Jul;10(7):3492–3504. doi: 10.1128/mcb.10.7.3492. [DOI] [PMC free article] [PubMed] [Google Scholar]
  33. 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]
  34. Spieth J., Brooke G., Kuersten S., Lea K., Blumenthal T. Operons in C. elegans: polycistronic mRNA precursors are processed by trans-splicing of SL2 to downstream coding regions. Cell. 1993 May 7;73(3):521–532. doi: 10.1016/0092-8674(93)90139-h. [DOI] [PubMed] [Google Scholar]
  35. Young J. R., Donelson J. E., Majiwa P. A., Shapiro S. Z., Williams R. O. analysis of genomic rearrangements associated with two variable antigen genes of Trypanosoma brucei. Nucleic Acids Res. 1982 Feb 11;10(3):803–819. doi: 10.1093/nar/10.3.803. [DOI] [PMC free article] [PubMed] [Google Scholar]

Articles from Nucleic Acids Research are provided here courtesy of Oxford University Press

RESOURCES