AUTHOR=Chiurillo Miguel A. , Moraes Barros Roberto R. , Souza Renata T. , Marini Marjorie M. , Antonio Cristiane R. , Cortez Danielle R. , Curto María Á. , Lorenzi Hernán A. , Schijman Alejandro G. , Ramirez José L. , da Silveira José F. 

TITLE=Subtelomeric I-SceI-Mediated Double-Strand Breaks Are Repaired by Homologous Recombination in Trypanosoma cruzi

JOURNAL=Frontiers in Microbiology

VOLUME=7

YEAR=2016

URL=https://www.frontiersin.org/journals/microbiology/articles/10.3389/fmicb.2016.02041

DOI=10.3389/fmicb.2016.02041

ISSN=1664-302X

ABSTRACT=<p><italic>Trypanosoma cruzi</italic> chromosome ends are enriched in surface protein genes and pseudogenes (e.g., trans-sialidases) surrounded by repetitive sequences. It has been proposed that the extensive sequence variability among members of these protein families could play a role in parasite infectivity and evasion of host immune response. In previous reports we showed evidence suggesting that sequences located in these regions are subjected to recombination. To support this hypothesis we introduced a double-strand break (DSB) at a specific target site in a <italic>T. cruzi</italic> subtelomeric region cloned into an artificial chromosome (pTAC). This construct was used to transfect <italic>T. cruzi</italic> epimastigotes expressing the I-SceI meganuclease. Examination of the repaired sequences showed that DNA repair occurred only through homologous recombination (HR) with endogenous subtelomeric sequences. Our findings suggest that DSBs in subtelomeric repetitive sequences followed by HR between them may contribute to increased variability in <italic>T. cruzi</italic> multigene families.</p>