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Telomere structure and function in trypanosomes: a proposal

Nature Reviews Microbiology volume 5, pages 70–75 (2007)Cite this article

Abstract

Telomeres are specialized DNA–protein complexes that stabilize chromosome ends, protecting them from nucleolytic degradation and illegitimate recombination. Telomeres form a heterochromatic structure that can suppress the transcription of adjacent genes. These structures might have additional roles in Trypanosoma brucei, as the major surface antigens of this parasite are expressed during its infectious stages from subtelomeric loci. We propose that the telomere protein complexes of trypanosomes and vertebrates are conserved and offer the hypothesis that growth and breakage of telomeric repeats has an important role in regulating parasite antigenic variation in trypanosomes.

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Figure 1: Life-cycle stages and the surface coat of Trypanosoma brucei.
Figure 2: Evolution of telomere sequences.
Figure 3: Telomere protein complexes.
Figure 4: Telomere proteins of Trypanosoma brucei.
Figure 5: Telomere length, breakage and the frequency of antigenic variation: a model.

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Acknowledgements

We are grateful to Titia de Lange, Joachim Lingner, Ed Louis and the members of the Cross laboratory for excellent advice and discussions. Our work on telomeres was supported by the National Institutes of Health. We apologize to authors whose original work could not always be cited due to length restrictions.

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  1. Bibo Li

    Present address: Department of Biology, Geology and Environmental Sciences, Cleveland State University, 2121 Euclid Avenue, Cleveland, 44115, Ohio, USA

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  1. The Rockefeller University, 1230 York Avenue, New York, 10021, New York, USA

    Oliver Dreesen, Bibo Li & George A. M. Cross

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Correspondence to George A. M. Cross.

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DATABASES

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Candida albicans

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Kluyveromyces lactis

Plasmodium falciparum

Saccharomyces cerevisiae

Schizosaccharomyces pombe

Trypanosoma brucei

Trypanosoma cruzi

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Dreesen, O., Li, B. & Cross, G. Telomere structure and function in trypanosomes: a proposal. Nat Rev Microbiol 5, 70–75 (2007). https://doi.org/10.1038/nrmicro1577

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