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  • The EMBO Journal (2005) 24, 4029 - 4040
  • doi:10.1038/sj.emboj.7600862

Published online: 17 November 2005

The F1-ATP synthase complex in bloodstream stage trypanosomes has an unusual and essential function

Achim Schnaufer1, G Desmond Clark-Walker2, Alodie G Steinberg1 and Ken Stuart1,3

  1. Seattle Biomedical Research Institute, Seattle, WA, USA
  2. Molecular Genetics and Evolution, Research School of Biological Sciences, The Australian National University, Canberra, ACT, Australia
  3. Department of Pathobiology, University of Washington, Seattle, WA, USA

Correspondence to:

Achim Schnaufer, Seattle Biomedical Research Institute, 307 Westlake Ave N, Suite 500, Seattle, WA 98109-5219, USA. Tel.: +1 206 256 7488; Fax: +1 206 256 7229; E-mail: achim.schnaufer@sbri.org

Ken Stuart, Seattle Biomedical Research Institute, 307 Westlake Ave N, Suite 500, Seattle, WA 98109-5219, USA. Tel.: +1 206 256 7316; Fax: +1 206 256 7229; E-mail: ken.stuart@sbri.org

Received 4 May 2005; Accepted 10 October 2005

Survival of bloodstream form Trypanosoma brucei, the agent of African sleeping sickness, normally requires mitochondrial gene expression, despite the absence of oxidative phosphorylation in this stage of the parasite's life cycle. Here we report that silencing expression of the alpha subunit of the mitochondrial F1-ATP synthase complex is lethal for bloodstream stage T. brucei as well as for T. evansi, a closely related species that lacks mitochondrial protein coding genes (i.e. is dyskinetoplastic). Our results suggest that the lethal effect is due to collapse of the mitochondrial membrane potential, which is required for mitochondrial function and biogenesis. We also identified a mutation in the gamma subunit of F1 that is likely to be involved in circumventing the requirement for mitochondrial gene expression in another dyskinetoplastic form. Our data reveal that the mitochondrial ATP synthase complex functions in the bloodstream stage opposite to that in the insect stage and in most other eukaryotes, namely using ATP hydrolysis to generate the mitochondrial membrane potential.

  • Keywords:

    • ATP synthase,
    • dyskinetoplasty,
    • mitochondria,
    • RNA editing,
    • trypanosome