Characterization of a Potential Glucose Transporter in \u3ci\u3eTrypanosoma brucei\u3c/i\u3e

Trypanosoma brucei, the African trypanosome, is an organism heavily dependent on glucose for ATP production during the infectious stage of its life cycle. Here, we have explored the role of an uncharacterized protein designated “novel glucose transporter” (NGT) as a potential glucose transporter. Sequence analyses suggests that NGT shares similarities (either at the primary sequence level or structurally) with Trypanosome Hexose Transporters 1 (TbTHT1), and human GLUT3, both of which are membrane sugar transporters. NGT was localized by fluorescence microscopy to subcellular structures consistent with lysosomes. Silencing NGT expression with RNA interference in parasites resulted in a growth defect in high glucose media, but not in low glucose media. Further genetic manipulation, to generate cells with single copy NGT disruptions, led to altered binding of the lectin concanavalin A to EP procyclin when compared to the parental cell line. To summarize, NGT, a protein with similarities to known sugar transporters, localizes near the lysosome, and interference with NGT expression plays a role in viability in high glucose media and alters parasite surface molecules glycosylation or expression