Functional characterization of TcCYC2 cyclin from Trypanosoma cruzi”.

POTENZA M.,; SCHENKMAN S; LAVERRIERE M.; TÉLLEZ - IÑÓN MARIA T

EXPERIMENTAL PARASITOLOGY

ACADEMIC PRESS INC ELSEVIER SCIENCE

Lugar: Amsterdam; Año: 2012 vol. 132 p. 537 - 545

0014-4894

In eukaryotes, an oscillating network of protein kinase activities drives the order and timing of the cellcycle progression. Complexes formed by cyclins associated to cyclin-dependent kinases (CDKs) are thecentral components of this network. Cyclins act as the activating subunits and their abundance is regulatedby different mechanisms in order to promote or prevent kinase activity. Protein synthesis, proteasomaldegradation and/or differential subcellular compartmentalization modulate cyclin expression levelsalong the cell cycle. We describe in this work the characterization of Trypanosoma cruzi Cyclin 2 (TcCYC2),which contributes to a better understanding of the cell cycle regulation in this protozoan parasite. We found TcCYC2 exhibited cyclin function in a yeast complementation assay and over-expression of hemagglutinin tagged TcCYC2-HA rendered shorter duplication times and smaller cell sizes in the epimastigote form of the parasite. Analysis of synchronized cultures showed that over-expression of TcCYC2-HA altered the timing epimastigotes pass through G2/M boundary or cytokinesis. Taken together, our results showed that TcCYC2 is a functional cyclin whose over-expression modifies the dynamics of the cell cycle as well as the morphology of epimastigote forms of T. cruzi,  suggesting it plays an important role in the cell cycle regulation machinery.