TY - JOUR
T1 - Cloning and characterization of DNA polymerase η from Trypanosoma cruzi
T2 - Roles for translesion bypass of oxidative damage
AU - De Moura, Michelle Barbi
AU - Schamber-Reis, Bruno Luiz Fonseca
AU - Silva, Danielle Gomes Passos
AU - Rajão, Matheus Andrade
AU - Macedo, Andréa Mara
AU - Franco, Glória Regina
AU - Pena, Sérgio Danilo Junho
AU - Teixeira, Santuza Maria Ribeiro
AU - Machado, Carlos Renato
PY - 2009/6
Y1 - 2009/6
N2 - We report the cloning and characterization of the DNA polymerase η gene from Trypanosoma cruzi (TcPolg), the causative agent of Chagas disease. This protein, which can bypass cyclobutane pyrimidine dimers, contains motifs that are conserved between Y family polymerases. In vitro assays showed that the recombinant protein is capable of synthesizing DNA in undamaged primer-templates. Intriguingly, T. cruzi overexpressing TcPolg does not increase its resistance to UV-light (with or without caffeine) or cisplatin, despite the ability of the protein to enhance UV resistance in a RAD30 mutant of Saccharomyces cerevisiae. Parasites overexpressing TcPolg are also unable to restore growth after treatment with zeocin or gamma irradiation. T. cruzi overexpressing TcPolg are more resistant to treatment with hydrogen peroxide (H2O2) compared to nontransfected cells. The observed H2O2 resistance could be associated with its ability to bypass 8-oxoguanine lesions in vitro. The results presented here suggest that TcPolh is able to bypass UV and oxidative lesions. However the overexpression of the gene only interferes in response to oxidative lesions, possibly due to the presence of these lesions during the S phase.
AB - We report the cloning and characterization of the DNA polymerase η gene from Trypanosoma cruzi (TcPolg), the causative agent of Chagas disease. This protein, which can bypass cyclobutane pyrimidine dimers, contains motifs that are conserved between Y family polymerases. In vitro assays showed that the recombinant protein is capable of synthesizing DNA in undamaged primer-templates. Intriguingly, T. cruzi overexpressing TcPolg does not increase its resistance to UV-light (with or without caffeine) or cisplatin, despite the ability of the protein to enhance UV resistance in a RAD30 mutant of Saccharomyces cerevisiae. Parasites overexpressing TcPolg are also unable to restore growth after treatment with zeocin or gamma irradiation. T. cruzi overexpressing TcPolg are more resistant to treatment with hydrogen peroxide (H2O2) compared to nontransfected cells. The observed H2O2 resistance could be associated with its ability to bypass 8-oxoguanine lesions in vitro. The results presented here suggest that TcPolh is able to bypass UV and oxidative lesions. However the overexpression of the gene only interferes in response to oxidative lesions, possibly due to the presence of these lesions during the S phase.
KW - DNA polymerase η
KW - Functional complementation
KW - Translesion synthesis
KW - Trypanosoma cruzi
UR - http://www.scopus.com/inward/record.url?scp=67549102396&partnerID=8YFLogxK
U2 - 10.1002/em.20450
DO - 10.1002/em.20450
M3 - Artículo Científico
C2 - 19229999
AN - SCOPUS:67549102396
SN - 0893-6692
VL - 50
SP - 375
EP - 386
JO - Environmental and Molecular Mutagenesis
JF - Environmental and Molecular Mutagenesis
IS - 5
ER -
