Overexpression of TcAUK1 in epimastigotes of Trypanosoma cruzi induces chromatin alterations

FASSOLARI M; FLAWIÁ MM; ALONSO GD

Potrero de los Funes, San Luis.

Congreso; XLVII Reunion AnualSAIB; 2011

SAIB

Aurora kinase family members coordinate a range of events associated with mitosis and cytokinesis. Yeast contain a single aurora kinase homologue (Ipl1), while mammals contain three (Aurora A, B and C). Aurora A is important for centrosome maturation, segregation and the assembly of the mitotic spindle. Aurora B and the yeast Ipl1 are each considered chromosomal passenger proteins. Early in mitosis Aurora B phosphorylates Ser-10 on histone H3 contributing in Drosophila, but not in humans, towards chromosome condensation. The function of Aurora C is less well understood. In T. cruzi, we have previously identified three aurora kinases paralogs (TcAUK1, 2 and 3) establishing TcAUK1 as a nuclear protein whose protein expression is regulated in a cell cycle-dependent way. In the present study we generate TcAUK1 overexpressing epimastigotes and begin to evaluate their phenotype. By Southern, northern and western blot was confirmed their overexpressing condition and by indirect immunofluorescence was determined the nuclear localization of TcAUK1 in transfected parasites. In addition, overexpressing-parasite extracts showed higher kinase activity levels than controls. Interestingly, DAPI DNA staining showed an altered chromatin distribution in the overexpressing parasites when compared with the empty vector control suggesting a possible role for this enzyme in cell cycle regulation