PUBLICATION
            The ceramide synthase 2b gene mediates genomic sensing and regulation of sphingosine Levels during zebrafish embryogenesis
- Authors
 - Mendelson, K., Pandey, S., Hisano, Y., Carellini, F., Das, B., Hla, T., Evans, T.
 - ID
 - ZDB-PUB-170929-3
 - Date
 - 2017
 - Source
 - eLIFE 6: (Journal)
 - Registered Authors
 - Evans, Todd
 - Keywords
 - biochemistry, developmental biology, stem cells, zebrafish
 - MeSH Terms
 - 
    
        
        
            
                
- Homeostasis*
 - Oxidoreductases/metabolism*
 - Zebrafish/embryology*
 - Sphingosine/metabolism*
 - Animals
 - Gene Expression Regulation
 
 - PubMed
 - 28956531 Full text @ Elife
 
            Citation
        
        
            Mendelson, K., Pandey, S., Hisano, Y., Carellini, F., Das, B., Hla, T., Evans, T. (2017) The ceramide synthase 2b gene mediates genomic sensing and regulation of sphingosine Levels during zebrafish embryogenesis. eLIFE. 6.
        
    
                
                    
                        Abstract
                    
                    
                
                
            
        
        
    
        
            
            
 
    
    
        
    
    
    
        
                Sphingosine-1-phosphate (S1P) is generated through phosphorylation of sphingosine by sphingosine kinases (Sphk1 and Sphk2). We show that sphk2 maternal-zygotic mutant zebrafish embryos (sphk2MZ) display early developmental phenotypes, including a delay in epiboly, depleted S1P levels, elevated levels of sphingosine, and resistance to sphingosine toxicity. The sphk2MZ embryos also have strikingly increased levels of maternal transcripts encoding ceramide synthase 2b (Cers2b), and loss of Cers2b in sphk2MZ embryos phenocopies sphingosine toxicity. An upstream region of the cers2b promoter supports enhanced expression of a reporter gene in sphk2MZ embryos compared to wildtype embryos. Furthermore, ectopic expression of Cers2b protein itself reduces activity of the promoter, and this repression is relieved by exogenous sphingosine. Therefore, the sphk2MZ genome recognizes the lack of sphingosine kinase activity and up-regulates cers2b as a salvage pathway for sphingosine turnover. Cers2b can also function as a sphingolipid-responsive factor to mediate at least part of a feedback regulatory mechanism.
            
    
        
        
    
    
    
                
                    
                        Genes / Markers
                    
                    
                
                
            
        
        
    
        
            
            
        
        
    
    
    
                
                    
                        Expression
                    
                    
                
                
            
        
        
    
        
            
            
        
        
    
    
    
                
                    
                        Phenotype
                    
                    
                
                
            
        
        
    
        
            
            
        
        
    
    
    
                
                    
                        Mutations / Transgenics
                    
                    
                
                
            
        
        
    
        
            
            
        
        
    
    
    
                
                    
                        Human Disease / Model
                    
                    
                
                
            
        
        
    
        
            
            
        
        
    
    
    
                
                    
                        Sequence Targeting Reagents
                    
                    
                
                
            
        
        
    
        
            
            
        
        
    
    
    
                
                    
                        Fish
                    
                    
                
                
            
        
        
    
        
            
            
        
        
    
    
    
                
                    
                        Orthology
                    
                    
                
                
            
        
        
    
        
            
            
        
        
    
    
    
                
                    
                        Engineered Foreign Genes
                    
                    
                
                
            
        
        
    
        
            
            
        
        
    
    
    
                
                    
                        Mapping