Inorganic phosphate modulates the cell division and differentiation in Trypanosoma rangeli
Santos, A. L. A.; Dick, C. F.; Fonseca de Souza, A. L.; Meyer-Fernandes, J. R.
Laboratório de Bioquímica Celular, IBqM, CCS, UFRJ, RJ. E-mail: santosala@bioqmed.ufrj.br
Trypanosoma rangeli is a South American trypanosoma, considered harmless to humans and animals although can infect triatomines. After the ingestion of trypomastigote forms during the blood meal, T. rangeli differentiate into short epimastigotes, proliferate in digestive tract, across the intestinal barrier and achieve haemolymph, where long forms are founded. Parasites complete your development in the lumen of salivary gland of insect, where metacyclogenesis takes place.
Inorganic phosphate is an important nutrient to all cellular functions. The phosphate is an essential compound to the cell growth and production of many cellular components as nucleic acids, lipids, sugars, among others. This fact gives importance to the study of proteins kinases and phosphatases, the proteins that control the phosphorylation-dephosphorylation events. These events contribute to the parasite-host cell interaction in many aspects as cell division and differentiation, nutrients acquisition and cell adhesion.
In this work, we investigate the role of ecto-phosphatase of T. rangeli on the cell division and differentiation. We evaluate the percentage of short and long forms of T. rangeli during the cell proliferation at the low- or high-phosphate culture medium.
We observed that when cell proliferation was arrested in low-phosphate concentration medium, no long epimastigote form was founded at the culture medium. At the high-phosphate medium, cells exhibit a normal growth curve and the number of short forms decreased at the tenth day of culture when the long forms begin to appear. The initial phosphate concentration was reduced to 20% at the fifteenth day for the cells maintained at the high-phosphate culture medium while no significant change was observed for the phosphate-starved cells. Taken together, these results suggest that the inorganic phosphate is a nutrient required to cell division and differentiation in T. rangeli.
Supported by CNPq, CAPES and FAPERJ.
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