PUBLICATION

Heat stress modulates nucleotide excision repair capacity in zebrafish (Danio rerio) early and mid-early embryos via distinct mechanisms

Authors
Chien, L.C., Wu, Y.H., Ho, T.N., Huang, Y.Y., Hsu, T.
ID
ZDB-PUB-190902-27
Date
2019
Source
Chemosphere   238: 124653 (Journal)
Registered Authors
Hsu, Todd
Keywords
Heat stress, Nucleotide excision repair, UV, Zebrafish embryos
MeSH Terms
  • Animals
  • DNA/metabolism
  • DNA Damage*
  • DNA Repair*
  • Embryo, Nonmammalian/metabolism
  • Gene Expression
  • Heat-Shock Response/genetics*
  • Time Factors
  • Ultraviolet Rays/adverse effects*
  • Zebrafish/embryology
  • Zebrafish/genetics*
  • Zebrafish/metabolism
  • Zebrafish Proteins/genetics
PubMed
31473528 Full text @ Chemosphere
Abstract
Discharge of heated effluent at 8-12 °C above ambient into water areas is known to retard the growth of aquatic organisms due to heat stress. Nucleotide excision repair (NER) maintains genome integrity by removing helix-distorting adducts such as UV-induced DNA lesions. This study explored how NER in zebrafish (Danio rerio) embryos at different hours post fertilization (hpf) responded to + 8.5 °C heat shock for 30 min. Our transcription-based repair assay monitoring the ability of zebrafish extracts to upregulate a UV-suppressed gene expression detected a 2-fold increase of NER capacity in 10 hpf early embryos after heat stress. In contrast, heat stress caused a mild inhibition of NER capacity in 24 hpf mid-early embryos. Heat-treated and untreated 10 hpf zebrafish extracts displayed similar levels of UV-damaged-DNA binding activities, while an apparently weaker (6-4) photoproduct (6-4 PP) binding activity was present in heat-stressed 24 hpf zebrafish extracts. Heat stress enhanced UV-induced NER in 10 hpf embryos by increasing the efficiency of damage incision/excision based on both genomic DNA electrophoresis and terminal deoxytransferase (TdT)-mediated end labeling assay. UV-irradiated embryos preexposed to heat stress produced a significantly larger amount of NER-associated DNA fragments about 20-30 nucleotides in length than embryos only heat-treated or irradiated. Correlated with its inhibitory effect on 6-4 PP damage recognition, heat stress downregulated damage incision/excision activities in 24 hpf embryos. Hence, thermal stress may positively or negatively modulate NER capacity in zebrafish embryos at different stages by targeting at the step of DNA incision/excision or damage recognition.
Genes / Markers
Figures
Expression
Phenotype
Mutations / Transgenics
Human Disease / Model
Sequence Targeting Reagents
Fish
Antibodies
Orthology
Engineered Foreign Genes
Mapping