Nutrient availability regulates proline/alanine transporters in Trypanosoma brucei.

摘要: Trypanosoma brucei is a species of unicellular parasite that can cause severe diseases in livestock and humans, including African trypanosomiasis Chagas disease. Adaptation to diverse environments changes nutritional conditions are essential for T. establish an infection when changing hosts, or during invasion different host tissues. One such adaptation the ability rapidly switch its energy metabolism from glucose mammalian blood proline catabolism insect stages vice versa. However, mechanisms support parasite's response nutrient availability remain unclear. Using RNAseq qRT-PCR, we investigated amino acid starvation found increased mRNA levels several transporters, all genes transporter AAT7-B subgroup. Functional characterization revealed members plasma membrane-localized expressed Saccharomyces cerevisiae supported uptake proline, alanine cysteine, while other acids were poorly recognized. All showed preference which transported with high low affinity. RNAi-mediated downregulation resulted reduction intracellular concentrations growth arrest under cultured procyclic form parasites. Taken together, these results suggest role transporters catabolism.