http://scholars.ntou.edu.tw/handle/123456789/24629
Title: | Thallium(I) induces a prolonged inhibition of (6-4)photoproduct binding and UV damage excision repair activities in zebrafish (Danio rerio) embryos via protein inactivation | Authors: | Huang, Ya-Yun Paul, Ganjai Vikram Hsu, Todd |
Keywords: | 6-4 photoproduct;Thallium;UV;Zebrafish | Issue Date: | 2023 | Publisher: | ELSEVIER IRELAND LTD | Journal Volume: | 388 | Source: | CHEMICO-BIOLOGICAL INTERACTIONS | Abstract: | Cyclobutane pyrimidine dimer (CPD) and (6-4)photoproduct (6-4 PP) are two major types of UV-induced DNA lesion and 6-4 PP is more mutagenic than CPD. Activated by lesion detection, nucleotide excision repair (NER) eliminates CPDs and 6-4 PPs. Thallium (Tl) is a toxic metal existing primarily as Tl+ in the aquatic environment. Ingestion of Tl+-contaminated foods and water is a major route of human poisoning. As Tl+ may inhibit enzyme activities via binding to sulfhydryl groups, this study explored if Tl+ could intensify UV mutagenicity by inactivating NER-linked damage recognition factors using zebrafish (Danio rerio) embryo as a model system. Incubation of Tl+ (as thallium nitrate) at 0.1-0.4 mu g/mL with zebrafish extracts for 20 min caused a concentrationdependent inhibition of 6-4 PP binding activities as shown by a photolesion-specific band shift assay, while CPD binding activities were insensitive to Tl+. The ability of Tl+ to suppress 6-4 PP detection was stronger than that of Hg2+. Exposure of zebrafish embryos at 1 h post fertilization (hpf) to Tl+ at 0.4-1 mu g/mL for 9 or 71 h also specifically inhibited 6-4 PP detection, indicating that Tl+ induced a prolonged inhibition of 6-4 PP sensing ability primarily via its direct interaction with damage recognition molecules. Tl+-mediated inhibition of 6-4 PP binding in embryos at distinct stages resulted in a suppression of NER capacity monitored by a transcriptionbased DNA repair assay. Our results revealed the potential of Tl+ to enhance UV mutagenicity by disturbing the removal of 6-4 PP through repressing the lesion detection step of NER. |
URI: | http://scholars.ntou.edu.tw/handle/123456789/24629 | ISSN: | 0009-2797 | DOI: | 10.1016/j.cbi.2023.110837 |
Appears in Collections: | 生命科學暨生物科技學系 |
Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.