Trypanosoma brucei aquaglyceroporins facilitate the uptake of arsenite and antimonite in a pH dependent way.
BACKGROUND
Trypanosoma brucei is a primitive parasitic protozoan that thrives in diverse environments such as the midgut of the tsetse fly and the blood of a mammalian host. For an adequate adaptation to these environments, the parasite's aquaglyceroporins play an important role.


RESULTS
In order to test their ability to transport trivalent arsenic and antimony, we expressed the three known Trypanosoma brucei aquaglyceroporins (TbAQPs) in the heterologous systems of yeast null aquaporin mutant and Xenopus laevis oocytes. For both expression systems, we found a pH dependent intracellular accumulation of As(III) or Sb(III) mediated by all of the three TbAQPs, with the exception of TbAQP1-As(III) uptake. Additionally, we observed that Trypanosoma brucei aquaglyceroporins allow the passage of As(III) in both directions.


CONCLUSIONS
Taken together, these results demonstrated that T. brucei aquaglyceroporins can serve as entry routes for As(III) and Sb(III) into the parasitic cell, and that this uptake is pH sensitive. Therefore, aquaporins of protozoan parasites may be considered useful as a vehicle for drug delivery.
Institute for Anatomy, Central University of Venezuela, Caracas, Venezuela.
Néstor L
NL
Uzcátegui
Katherine
K
Figarella
Bjoern
B
Bassarak
Nestor W
NW
Meza
Rita
R
Mukhopadhyay
Jose L
JL
Ramirez
Michael
M
Duszenko
D000965:Antimony / Q000378:metabolism*; D051397:Aquaglyceroporins / Q000378:metabolism*; D018053:Arsenites / Q000378:metabolism*; D001692:Biological Transport; D006863:Hydrogen-Ion Concentration; D014346:Trypanosoma brucei brucei / Q000378:metabolism*
D051397:Aquaglyceroporins; D018053:Arsenites; C061374:antimonite; D000965:Antimony; C015001:arsenite