Project description:Purpose: The is a major paucity of knowledge regarding the biology of Trypanosoma congolense, a protozoan parasite primarily responsible for Animal African Trypanosomiasis. In contrast, the closely related species T. brucei, is far better understood. To characterise core metabolism in T. congolense, comparative RNAseq analysis was undertaken to assess similarities and differences in transcript levels of genes associated with metabolism Methods: Samples from both in vitro culture and ex vivo (isolated from murine infections) bloodstream-form T. brucei and T. congolense were RNA-sequenced. Data was analyzed using a pipeline that allows for inter-species comparison Results: T. congolense exhibits increased transcript abundance in genes associated with the glycosomal succinate shunt, as well as mitochondrial metabolism, in particular the catabolism of pyruvate to acetate, compared to T. brucei. These differences occur both in vitro and ex vivo. Furthermore there are differences in nucleotide metabolism, and transcript levels of genes involved in fatty acid synthesis are reduced in T. congolense compared to T. brucei. Conclusions: Comparative RNAseq between two closely related species provided a detailed overview of similarities and differences in core metabolism. This carries significant implications for adaptation to in vitro culture, and drug efficacy, mode of action and mode of resistance.
Project description:Trypanosoma brucei gambiense is the causative agent of the fatal human disease African sleeping sickness. Using Digital Gene Expression we have compared the transcriptome of a group 1 T.b.gambiense (Eliane) and a T.b.brucei (STIB 247).
Project description:T. brucei PF cells were treated with several chemical reagents and anti-trypanosomatid drugs. The effect of each chemical perturbation on the transcriptome of T. brucei was examined by transcript profiling of treated vs. control cells. The results indicated widespread changes, suggesting that the transcriptome of T. brucei is highly responsive to environmental factors that perturb its metabolic and biological pathways.
Project description:The host range of African trypanosomes is influenced by innate protective molecules in the blood of primates. A subfraction of human high-density lipoprotein (HDL) containing apolipoprotein A-I, apolipoprotein L-I, and haptoglobin-related protein is toxic to Trypanosoma brucei brucei but not the human sleeping sickness parasite Trypanosoma brucei rhodesiense. It is thought that T. b. rhodesiense evolved from a T. b. brucei-like ancestor and expresses a defense protein that ablates the antitrypanosomal activity of human HDL. To directly investigate this possibility, we developed an in vitro selection to generate human HDL-resistant T. b. brucei. Here we show that conversion of T. b. brucei from human HDL sensitive to resistant correlates with changes in the expression of the variant surface glycoprotein (VSG) and abolished uptake of the cytotoxic human HDLs. Complete transcriptome analysis of the HDL-susceptible and -resistant trypanosomes confirmed that VSG switching had occurred but failed to reveal the expression of other genes specifically associated with human HDL resistance, including the serum resistance-associated gene (SRA) of T. b. rhodesiense. In addition, we found that while the original active expression site was still utilized, expression of three expression site-associated genes (ESAG) was altered in the HDL-resistant trypanosomes. These findings demonstrate that resistance to human HDLs can be acquired by T. b. brucei. Keywords: Trypanosoma, VSG, antigenic switching, HDL-resistance
