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
  • Animals
  • Gene Expression Regulation
  • Homeostasis*
  • Oxidoreductases/metabolism*
  • Sphingosine/metabolism*
  • Zebrafish/embryology*
PubMed
28956531 Full text @ Elife
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
Figures
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Expression
Phenotype
Mutations / Transgenics
Human Disease / Model
Sequence Targeting Reagents
Fish
Antibodies
Orthology
Engineered Foreign Genes
Mapping