PUBLICATION
            Pxr- and Nrf2- mediated induction of ABC transporters by heavy metal ions in zebrafish embryos
- Authors
 - Hu, J., Tian, J., Zhang, F., Wang, H., Yin, J.
 - ID
 - ZDB-PUB-191011-28
 - Date
 - 2019
 - Source
 - Environmental pollution (Barking, Essex : 1987) 255: 113329 (Journal)
 - Registered Authors
 - Hu, Jia, Tian, Jingjing, Wang, Han, Yin, Jian
 - Keywords
 - ABC transporters, Heavy metal ions, Nuclear factor E2 related factor 2, Pregnane X receptor, Zebrafish embryo
 - MeSH Terms
 - 
    
        
        
            
                
- Inactivation, Metabolic
 - Receptors, Aryl Hydrocarbon/metabolism
 - Zebrafish Proteins/metabolism
 - Zebrafish/embryology*
 - Receptors, Steroid/genetics
 - Animals
 - ATP-Binding Cassette Transporters/metabolism*
 - Transcription Factors/metabolism
 - NF-E2-Related Factor 2/genetics*
 - Glutathione/metabolism
 - Metals, Heavy/toxicity*
 - Pregnane X Receptor/genetics*
 
 - PubMed
 - 31600704 Full text @ Environ. Pollut.
 
            Citation
        
        
            Hu, J., Tian, J., Zhang, F., Wang, H., Yin, J. (2019) Pxr- and Nrf2- mediated induction of ABC transporters by heavy metal ions in zebrafish embryos. Environmental pollution (Barking, Essex : 1987). 255:113329.
        
    
                
                    
                        Abstract
                    
                    
                
                
            
        
        
    
        
            
            
 
    
    
        
    
    
    
        
                Transcription factors including pregnane X receptor (Pxr) and nuclear factor-erythroid 2-related factor-2 (Nrf2) are important modulators of Adenosine triphosphate-binding cassette (ABC) transporters in mammalian cells. However, whether such modulation is conserved in zebrafish embryos remains largely unknown. In this manuscript, pxr- and nrf2-deficient models were constructed with CRISPR/Cas9 system, to evaluate the individual function of Pxr and Nrf2 in the regulation of ABC transporters and detoxification of heavy metal ions like Cd2+ and Ag+. As a result, both Cd2+ and Ag+ conferred extensive interactions with ABC transporters in wild type (WT) embryos: their accumulation and toxicity were affected by the activity of ABC transporters, and they significantly induced the mRNA expressions of ABC transporters. These induction effects were reduced by the mutation of pxr and nrf2, but elevations in the basal expression of ABC transporters compensated for the loss of their inducibility. This could be an explanation for remaining transporter function in both mutant models as well as the unaltered toxicity of metal ions in pxr-deficient embryos. However, mutation of nrf2 disrupted the production of glutathione (GSH), resulting in the enhanced toxicity of Cd2+/Ag+ in zebrafish embryos. In addition, elevated expressions of other transcription factors like aryl hydrocarbon receptor (ahr) 1b, peroxisome proliferator-activated receptor (ppar)-β, and nrf2 were found in pxr-deficient models without any treatment, while enhanced induction of ahr1b, ppar-β and pxr could only be seen in nrf2-deficient embryos after the treatment of metal ions, indicating different compensation phenomena for the absence of transcription factors. After all, pxr-deficient and nrf2-deficient zebrafish embryos are useful tools in the functional investigation of Pxr and Nrf2 in the early life stages of aquatic organisms. However, the compensatory mechanisms should be taken into consideration when interpreting the results and need in-depth investigations.
            
    
        
        
    
    
    
                
                    
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                        Human Disease / Model
                    
                    
                
                
            
        
        
    
        
            
            
        
        
    
    
    
                
                    
                        Sequence Targeting Reagents
                    
                    
                
                
            
        
        
    
        
            
            
        
        
    
    
    
                
                    
                        Fish
                    
                    
                
                
            
        
        
    
        
            
            
        
        
    
    
    
                
                    
                        Orthology
                    
                    
                
                
            
        
        
    
        
            
            
        
        
    
    
    
                
                    
                        Engineered Foreign Genes
                    
                    
                
                
            
        
        
    
        
            
            
        
        
    
    
    
                
                    
                        Mapping