Comprehensive analysis of sphingosine‐1‐phosphate receptor mutants during zebrafish embryogenesis

Abstract

The lipid mediator sphingosine-1-phosphate (S1P) regulates various physiological and pathological phenomena such as angiogenesis and oncogenesis. Secreted S1P associates with the G-protein-coupled S1P receptors (S1PRs), leading to the activation of downstream signaling molecules. In mammals, five S1prs have been identified and the genetic disruption of a single S1pr1 gene causes vascular defects. In zebrafish, seven s1prs have been isolated. We found that individual s1prs showed unique expression patterns with some overlapping expression domains during early embryogenesis. We generated all s1pr single-mutant zebrafish by introducing premature stop codons in their coding regions using transcription activator-like effector nucleases and analyzed their phenotypes during early embryogenesis. Zygotic s1pr1, s1pr3a, s1pr3b, s1pr4, s1pr5a and s1pr5b mutants showed no developmental defects and grew into adults, whereas zygotic s1pr2 mutant showed embryonic lethality with a cardiac defect, showing quite distinct embryonic phenotypes for individual S1pr mutants between zebrafish and mouse. We further generated maternal-zygotic s1pr1, s1pr3a, s1pr3b, s1pr4, s1pr5a and s1pr5b mutants and found that these maternal-zygotic mutants also showed no obvious developmental defects, presumably suggesting the redundant functions of the S1P receptor-mediated signaling in zebrafish.

The ceramide synthase 2b gene mediates genomic sensing and regulation of sphingosine levels during zebrafish embryogenesis

“…The dramatic blastoderm constriction phenotype is remarkably similar to the maternal-zygotic betty boop ( bbp ) mutant embryo ( Holloway et al, 2009 ), suggesting that it could also involve defects in a p38/MAPKAPK2 pathway. Although S1P 2 couples through Gα 13 to control cell migration ( Ye and Lin, 2013 ), and Gα 13 signaling plays an important role in epiboly progression ( Solnica-Krezel, 2006 ), the receptor-dependent pathway seems less likely to be involved, since similar phenotypes are not observed in embryos lacking S1P receptors ( Hisano et al, 2015b ).…”

Beyond Immune Cell Migration: The Emerging Role of the Sphingosine-1-phosphate Receptor S1PR4 as a Modulator of Innate Immune Cell Activation

“…S1PR4-deficient mice and zebrafish are born at normal frequencies and do not show an obvious abnormal phenotype when they remain unchallenged [ 76 , 77 ]. This indicates a negligible influence of S1PR4 during embryonic development and on the development of individual immune cell populations, although S1PR4 is highly expressed by hematopoietic stem cells [ 78 , 79 ].…”

Post-transcriptional Modulation of Sphingosine-1-Phosphate Receptor 1 by miR-19a Affects Cardiovascular Development in Zebrafish

“…However a recent paper by Hisano et al analyzed all of the available s1pr zebrafish mutants generated by TALEN-mediated frameshift mutations. They demonstrated that none of the s1pr mutants showed developmental defects with the exception of s1pr2 mutant which exhibits embryonic lethality arising from its cardiac defect (Hisano et al, 2015 ). These data suggest a previously unrevealed redundancy in functions of the S1P receptor-mediated signaling in zebrafish similarly to the partially overlapping expression of S1P receptors observed in mouse (Means and Brown, 2009 ).…”