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. 1991 Apr 25;19(8):1745–1751. doi: 10.1093/nar/19.8.1745

A novel DNA nucleotide in Trypanosoma brucei only present in the mammalian phase of the life-cycle.

J Gommers-Ampt 1, J Lutgerink 1, P Borst 1
PMCID: PMC328099  PMID: 1674368

Abstract

The existence of an unusual form of DNA modification in the bloodstream form of the African trypanosome Trypanosoma brucei has been inferred from partial resistance to cleavage of nuclear DNA with PstI and PvuII (Bernards et al, 1984; Pays et al, 1984). This putative modification is correlated with the shut-off of telomeric Variant-specific Surface Glycoprotein (VSG) gene expression sites (ESs). The modification only affects inactive VSG genes with a telomeric location, and it is absent in procyclic (insect form) trypanosomes in which no VSG is made at all. Previous attempts to detect unusual nucleosides in T.brucei DNA were unsuccessful, but we now report the detection of two unusual nucleotides, called pdJ and pdV, in T.brucei DNA, using the 32P-postlabeling technique. Nucleotide pdV was present in both bloodstream form and procyclic T.brucei DNA and co-migrated in two different two-dimensional thin layer chromatography (2D-TLC) systems with hydroxymethyldeoxyuridine 5'-monophosphate (pHOMedU). In contrast, nucleotide pdJ was exclusively present in bloodstream form trypanosomal DNA. Levels of pdJ were higher in DNA enriched for telomeric sequences than in total genomic DNA and pdJ was also detected in other Kinetoplastida species exhibiting antigenic variation. Postlabeling and 2D-TLC analyses showed base J to be different from the known eukaryotic unusual DNA bases 5-methylcytosine, N6-methyladenine and hydroxymethyluracil, and also from (glucosylated) hydroxymethylcytosine, uracil, alpha-putrescinylthymine, 5-dihydroxypentyluracil and N6-carbamoylmethyladenine. We conclude that pdJ is a novel eukaryotic DNA nucleotide and that it is probably responsible for the partial resistance to cleavage by PvuII and PstI of inactive telomeric VSG genes. It may therefore be involved in the regulation of ES activity in bloodstream form trypanosomes.

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  1. Alegria A. H. Hydroxymethylation of pyrimidine mononucleotides with formaldehyde. Biochim Biophys Acta. 1967 Dec 19;149(2):317–324. doi: 10.1016/0005-2787(67)90159-1. [DOI] [PubMed] [Google Scholar]
  2. Arwert F., Venema G. Transfection of Bacillus subtilis with bacteriophage H1 DNA: fate of transfecting DNA and transfection enhancement in B. subtilis uur+ and uur- strains. Mol Gen Genet. 1974;128(1):55–72. doi: 10.1007/BF00267294. [DOI] [PubMed] [Google Scholar]
  3. Bernards A., Michels P. A., Lincke C. R., Borst P. Growth of chromosome ends in multiplying trypanosomes. Nature. 1983 Jun 16;303(5918):592–597. doi: 10.1038/303592a0. [DOI] [PubMed] [Google Scholar]
  4. 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]
  5. Bernards A., van Harten-Loosbroek N., Borst P. Modification of telomeric DNA in Trypanosoma brucei; a role in antigenic variation? Nucleic Acids Res. 1984 May 25;12(10):4153–4170. doi: 10.1093/nar/12.10.4153. [DOI] [PMC free article] [PubMed] [Google Scholar]
  6. Bird A. P. CpG-rich islands and the function of DNA methylation. Nature. 1986 May 15;321(6067):209–213. doi: 10.1038/321209a0. [DOI] [PubMed] [Google Scholar]
  7. Blackburn E. H., Challoner P. B. Identification of a telomeric DNA sequence in Trypanosoma brucei. Cell. 1984 Feb;36(2):447–457. doi: 10.1016/0092-8674(84)90238-1. [DOI] [PubMed] [Google Scholar]
  8. 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]
  9. Borst P., Hoeijmakers J. H. Kinetoplast DNA. Plasmid. 1979 Jan;2(1):20–40. doi: 10.1016/0147-619x(79)90003-9. [DOI] [PubMed] [Google Scholar]
  10. 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]
  11. Cedar H. DNA methylation and gene activity. Cell. 1988 Apr 8;53(1):3–4. doi: 10.1016/0092-8674(88)90479-5. [DOI] [PubMed] [Google Scholar]
  12. 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]
  13. Crozatier M., De Brij R. J., Den Engelse L., Johnson P. J., Borst P. Nucleoside analysis of DNA from Trypanosoma brucei and Trypanosoma equiperdum. Mol Biochem Parasitol. 1988 Nov;31(2):127–131. doi: 10.1016/0166-6851(88)90163-6. [DOI] [PubMed] [Google Scholar]
  14. 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]
  15. Dawid I. B., Brown D. D., Reeder R. H. Composition and structure of chromosomal and amplified ribosomal DNA's of Xenopus laevis. J Mol Biol. 1970 Jul 28;51(2):341–360. doi: 10.1016/0022-2836(70)90147-6. [DOI] [PubMed] [Google Scholar]
  16. 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]
  17. Dynan W. S. Understanding the molecular mechanism by which methylation influences gene expression. Trends Genet. 1989 Feb;5(2):35–36. doi: 10.1016/0168-9525(89)90016-4. [DOI] [PubMed] [Google Scholar]
  18. 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]
  19. Frenkel K., Cummings A., Solomon J., Cadet J., Steinberg J. J., Teebor G. W. Quantitative determination of the 5-(hydroxymethyl)uracil moiety in the DNA of gamma-irradiated cells. Biochemistry. 1985 Aug 13;24(17):4527–4533. doi: 10.1021/bi00338a007. [DOI] [PubMed] [Google Scholar]
  20. Gottesdiener K., Garciá-Anoveros J., Lee M. G., Van der Ploeg L. H. Chromosome organization of the protozoan Trypanosoma brucei. Mol Cell Biol. 1990 Nov;10(11):6079–6083. doi: 10.1128/mcb.10.11.6079. [DOI] [PMC free article] [PubMed] [Google Scholar]
  21. Gupta R. C., Reddy M. V., Randerath K. 32P-postlabeling analysis of non-radioactive aromatic carcinogen--DNA adducts. Carcinogenesis. 1982;3(9):1081–1092. doi: 10.1093/carcin/3.9.1081. [DOI] [PubMed] [Google Scholar]
  22. Hattman S. DNA methylation of T-even bacteriophages and of their nonglucosylated mutants: its role in P1-directed restriction. Virology. 1970 Oct;42(2):359–367. doi: 10.1016/0042-6822(70)90279-5. [DOI] [PubMed] [Google Scholar]
  23. Jeffreys A. J., Flavell R. A. A physical map of the DNA regions flanking the rabbit beta-globin gene. Cell. 1977 Oct;12(2):429–439. doi: 10.1016/0092-8674(77)90119-2. [DOI] [PubMed] [Google Scholar]
  24. Kropinski A. M., Bose R. J., Warren R. A. 5-(4-Aminobutylaminomethyl)uracil, an unusual pyrimidine from the deoxyribonucleic acid of bacteriophage phiW-14. Biochemistry. 1973 Jan 2;12(1):151–157. doi: 10.1021/bi00725a025. [DOI] [PubMed] [Google Scholar]
  25. MARKHAM R., SMITH J. D. Chromatographic studies of nucleic acids. 4. The nucleic acid of the turnip yellow mosaic virus including a note on the nucleic acid of the tomato bushy stunt virus. Biochem J. 1951 Sep;49(4):401–406. doi: 10.1042/bj0490401. [DOI] [PMC free article] [PubMed] [Google Scholar]
  26. Marmur J., Brandon C., Neubort S., Ehrlich M., Mandel M., Konvicka J. Unique properties of nucleic acid from Bacillus subtilis phage SP-15. Nat New Biol. 1972 Sep 20;239(90):68–70. doi: 10.1038/newbio239068a0. [DOI] [PubMed] [Google Scholar]
  27. 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]
  28. 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]
  29. Pays E., Laurent M., Delinte K., Van Meirvenne N., Steinert M. Differential size variations between transcriptionally active and inactive telomeres of Trypanosoma brucei. Nucleic Acids Res. 1983 Dec 10;11(23):8137–8147. doi: 10.1093/nar/11.23.8137. [DOI] [PMC free article] [PubMed] [Google Scholar]
  30. Rae P. M., Steele R. E. Modified bases in the DNAs of unicellular eukaryotes: an examination of distributions and possible roles, with emphasis on hydroxymethyluracil in dinoflagellates. Biosystems. 1978 Apr;10(1-2):37–53. doi: 10.1016/0303-2647(78)90027-8. [DOI] [PubMed] [Google Scholar]
  31. Reddy M. V., Gupta R. C., Randerath K. 32P-base analysis of DNA. Anal Biochem. 1981 Nov 1;117(2):271–279. doi: 10.1016/0003-2697(81)90722-3. [DOI] [PubMed] [Google Scholar]
  32. Rigby P. W., Dieckmann M., Rhodes C., Berg P. Labeling deoxyribonucleic acid to high specific activity in vitro by nick translation with DNA polymerase I. J Mol Biol. 1977 Jun 15;113(1):237–251. doi: 10.1016/0022-2836(77)90052-3. [DOI] [PubMed] [Google Scholar]
  33. Sloof P., Menke H. H., Caspers M. P., Borst P. Size fractionation of Trypanosoma brucei DNA: localization of the 177-bp repeat satellite DNA and a variant surface glycoprotein gene in a mini-chromosomal DNA fraction. Nucleic Acids Res. 1983 Jun 25;11(12):3889–3901. doi: 10.1093/nar/11.12.3889. [DOI] [PMC free article] [PubMed] [Google Scholar]
  34. Swinton D., Hattman S., Crain P. F., Cheng C. S., Smith D. L., McCloskey J. A. Purification and characterization of the unusual deoxynucleoside, alpha-N-(9-beta-D-2'-deoxyribofuranosylpurin-6-yl)glycinamide, specified by the phage Mu modification function. Proc Natl Acad Sci U S A. 1983 Dec;80(24):7400–7404. doi: 10.1073/pnas.80.24.7400. [DOI] [PMC free article] [PubMed] [Google Scholar]
  35. TEMPERLI A., TUERLER H., RUEST P., DANON A., CHARGAFF E. STUDIES OF THE NUCLEOTIDE ARRANGEMENT IN DEOXYRIBONUCLEIC ACIDS. IX. SELECTIVE DEGRADATION OF PYRIMIDINE DEOXYRIBONUCLEOTIDES. Biochim Biophys Acta. 1964 Nov 15;91:462–476. doi: 10.1016/0926-6550(64)90076-3. [DOI] [PubMed] [Google Scholar]
  36. Van der Ploeg L. H., Liu A. Y., Borst P. Structure of the growing telomeres of Trypanosomes. Cell. 1984 Feb;36(2):459–468. doi: 10.1016/0092-8674(84)90239-3. [DOI] [PubMed] [Google Scholar]
  37. 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]
  38. Warren R. A. Modified bases in bacteriophage DNAs. Annu Rev Microbiol. 1980;34:137–158. doi: 10.1146/annurev.mi.34.100180.001033. [DOI] [PubMed] [Google Scholar]
  39. Zomerdijk J. C., Ouellette M., ten Asbroek A. L., Kieft R., Bommer A. M., Clayton C. E., Borst P. The promoter for a variant surface glycoprotein gene expression site in Trypanosoma brucei. EMBO J. 1990 Sep;9(9):2791–2801. doi: 10.1002/j.1460-2075.1990.tb07467.x. [DOI] [PMC free article] [PubMed] [Google Scholar]

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