Functional study of elongator proteins in Trypanosoma cruzi

MEYER CG; TORRES HN; FLAWIÁ MM; ALONSO GD

Villa Carlos Paz. Cordoba, Argentina.

Congreso; XLIV Reunión Anual de la Sociedad Argentina de Investigación en Bioquímica y Biología Molecular (SAIB).; 2008

Sociedad Argentina de Investigación en Bioquímica y Biología Molecular

N-terminal tails of nucleosomal histones are subjected to post translational modifications (PTM) that regulate several cell processes such as chromatin structure, transcription, DNA damage repair and replication. Lysine acetylation of this tails is a dynamic PTM that involves histone acetyltransferases (HATs) and histone deacetylases (HDAC). Growing evidence correlate histone acetylation with gene activation, and histone deacetylation with gene repression. We have previously reported the PCR-amplification of a Trypanosoma cruzi sequence with Elp3 identity named TcElp3. This sequence was not able to complement an Elp3 deficient yeast strain and the recombinant protein expressed in bacteria did not show enzymatic activity. In this work we analyze the over-expression of TcElp3 in epimastigotes of CL Brener and Tulahuen 2 strains using pTREX vector. Immunofluorescence microscopy showed that TcElp3 has a perinuclear localization which is enhanced in over-expressing parasites. We also studied the effect of histone deacetylases inhibitors trichostatin A (TSA) and sodium butyrate on epimastigotes grown in vitro. When parasites were treated with 50 nM TSA strong proliferation inhibition was observed. In addition a sub G1 peak and cell cycle alterations were observed in flow cytometry DNA histogram. We are currently repeating these experiments with over-expressing parasites.