The overall objective of this proposal is to understand the structure, function, and developmental regulation of the mitochondrial ATP synthase of the parasitic protozoan Trypanosoma brucei. This critical enzyme couples membrane potential generated by the electron transport chain to synthesis of ATP. We have recently established that the enzyme is regulated through the life cycle of T. brucei, although not to the same extent as the cytochromes of the electron transport chain. We now wish to determine the nature of regulation of the ATP synthase through the bloodstream of the mammalian host and in the insect host.
Specific aims are to: 1. Examine the complete structure of the ATP synthase to determine whether the substructure of the complex may vary or whether the protein assembly or stability might play a regulatory role. 2. Establish whether interaction of regulatory proteins with the enzyme complex may be a component of the regulation of the ATP synthase in the developmental cycle. 3. Determine the primary sequence of genes encoding critical subunits of the ATP synthase at the genomic and cDNA level, to establish whether transcript editing occurs as a function of development and to determine whether editing occurs with both nuclear and mitochondrially encoded proteins. 4. Establish whether regulation of the ATP synthase complex may occur at the level of protein expression in T. brucei. Results from these experiments will give a better understanding of the structure and functional status of the ATP synthase and may yield insights into its role in energy metabolism through the developmental stages of T. brucei. We hope that the information we obtain will enable us to specifically target this bioenergetic enzyme complex by chemical means. Due to its central role in energy metabolism we believe it is an excellent candidate for such a chemotherapeutic approach.

National Institute of Health (NIH)
National Institute of Allergy and Infectious Diseases (NIAID)
Research Project (R01)
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Tropical Medicine and Parasitology Study Section (TMP)
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State University of New York at Buffalo
Schools of Medicine
United States
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Brown B, S V; Stanislawski, A; Perry, Q L et al. (2001) Cloning and characterization of the subunits comprising the catalytic core of the Trypanosoma brucei mitochondrial ATP synthase. Mol Biochem Parasitol 113:289-301
Brown B, S V; Chi, T B; Williams, N (2001) The Trypanosoma brucei mitochondrial ATP synthase is developmentally regulated at the level of transcript stability. Mol Biochem Parasitol 115:177-87
Brown, S V; Williams, N (1999) Analysis of the 60 S ribosomal protein L27a (L29) gene of Trypanosoma brucei. Int J Parasitol 29:731-6
Zhang, J; Ruyechan, W; Williams, N (1998) Developmental regulation of two nuclear RNA binding proteins, p34 and p37, from Trypanosoma brucei. Mol Biochem Parasitol 92:79-88
Chi, T B; Brown B, S V; Williams, N (1998) Subunit 9 of the mitochondrial ATP synthase of Trypanosoma brucei is nuclearly encoded and developmentally regulated. Mol Biochem Parasitol 92:29-38
Pitula, J; Ruyechan, W T; Williams, N (1998) Trypanosoma brucei: identification and purification of a poly(A)-binding protein. Exp Parasitol 88:157-60
Fuenmayor, J; Zhang, J; Ruyechan, W et al. (1998) Identification and characterization of two DNA polymerase activities present in Trypanosoma brucei mitochondria. J Eukaryot Microbiol 45:404-10
Zhang, J; Williams, N (1997) Purification, cloning, and expression of two closely related Trypanosoma brucei nucleic acid binding proteins. Mol Biochem Parasitol 87:145-58
Chi, T B; Choi, S Y; Williams, N (1996) The ATP synthase of Trypanosoma brucei is developmentally regulated by an inhibitor peptide. Arch Biochem Biophys 333:291-7
Williams, N (1994) The mitochondrial ATP synthase of Trypanosoma brucei: structure and regulation. J Bioenerg Biomembr 26:173-8