10.3389/fcimb.2018.00214.s003 Elisa Azuara-Liceaga Elisa Azuara-Liceaga Abigail Betanzos Abigail Betanzos Cesar S. Cardona-Felix Cesar S. Cardona-Felix Elizabeth J. Castañeda-Ortiz Elizabeth J. Castañeda-Ortiz Helios Cárdenas Helios Cárdenas Rosa E. Cárdenas-Guerra Rosa E. Cárdenas-Guerra Guillermo Pastor-Palacios Guillermo Pastor-Palacios Guillermina García-Rivera Guillermina García-Rivera David Hernández-Álvarez David Hernández-Álvarez Carlos H. Trasviña-Arenas Carlos H. Trasviña-Arenas Corina Diaz-Quezada Corina Diaz-Quezada Esther Orozco Esther Orozco Luis G. Brieba Luis G. Brieba Image_3_The Sole DNA Ligase in Entamoeba histolytica Is a High-Fidelity DNA Ligase Involved in DNA Damage Repair.JPEG Frontiers 2018 EhDNAligI protozoan DNA insults ligation repairing 8-oxoG adduct NER and BER pathways 2018-07-12 04:21:02 Figure https://frontiersin.figshare.com/articles/figure/Image_3_The_Sole_DNA_Ligase_in_Entamoeba_histolytica_Is_a_High-Fidelity_DNA_Ligase_Involved_in_DNA_Damage_Repair_JPEG/6808733 <p>The protozoan parasite Entamoeba histolytica is exposed to reactive oxygen and nitric oxide species that have the potential to damage its genome. E. histolytica harbors enzymes involved in DNA repair pathways like Base and Nucleotide Excision Repair. The majority of DNA repairs pathways converge in their final step in which a DNA ligase seals the DNA nicks. In contrast to other eukaryotes, the genome of E. histolytica encodes only one DNA ligase (EhDNAligI), suggesting that this ligase is involved in both DNA replication and DNA repair. Therefore, the aim of this work was to characterize EhDNAligI, its ligation fidelity and its ability to ligate opposite DNA mismatches and oxidative DNA lesions, and to study its expression changes and localization during and after recovery from UV and H<sub>2</sub>O<sub>2</sub> treatment. We found that EhDNAligI is a high-fidelity DNA ligase on canonical substrates and is able to discriminate erroneous base-pairing opposite DNA lesions. EhDNAligI expression decreases after DNA damage induced by UV and H<sub>2</sub>O<sub>2</sub> treatments, but it was upregulated during recovery time. Upon oxidative DNA damage, EhDNAligI relocates into the nucleus where it co-localizes with EhPCNA and the 8-oxoG adduct. The appearance and disappearance of 8-oxoG during and after both treatments suggest that DNA damaged was efficiently repaired because the mainly NER and BER components are expressed in this parasite and some of them were modulated after DNA insults. All these data disclose the relevance of EhDNAligI as a specialized and unique ligase in E. histolytica that may be involved in DNA repair of the 8-oxoG lesions.</p>