title: Sphingosine 1-phosphate regulation of extracellular signal-regulated kinase-1/2 in embryonic stem cells.
abstract: Recent evidence suggests that sphingosine 1-phosphate (S1P) regulates self-renewal of human embryonic stem (ES) cells and differentiation of mouse embryoid bodies (derived from mouse ES cells) to cardiomyocytes. We have investigated the role of S1P in regulating ERK-1/2 signaling in mouse ES cells. In this regard, we found that both mouse ES-D3 and CGR8 cells express S1P(1), S1P(2), S1P(3), and S1P(5) but lack S1P(4). The treatment of ES cells with S1P induced the activation of ERK-1/2 via a mechanism that was not mediated by S1P(1), S1P(2), or S1P(3). This was based on: (i) the failure of S1P(1), S1P(2), or S1P(3) antagonists to inhibit S1P-stimulated ERK-1/2 activation and (ii) the failure of SEW 2871 (S1P(1) receptor agonist) to stimulate ERK-1/2 activation. The treatment of ES cells with phytosphingosine 1-phosphate (phyto-S1P), which we show here is an agonist of the S1P(5) receptor, stimulated ERK-1/2 activation. These findings therefore suggest that S1P(5) may mediate the effects of S1P in terms of regulating ERK-1/2 signaling in ES cells. The S1P-dependent activation of ERK-1/2 was sensitive to inhibition by pertussis toxin (uncouples the G-protein, G(i) from GPCR), bisindolylmaleimide I (PKC inhibitor), and PP2 (c-Src inhibitor), but was not reduced by LY29004 (PI3K inhibitor) suggesting that S1P uses G(i)-, PKC-, and c-Src-dependent mechanisms to activate the ERK-1/2 pathway in ES cells.
authors.affiliation: Cell Biology Group, SIPBS, University of Strathclyde, Glasgow G4 0NR, United Kingdom.
authors.forename: Alayna
authors.initials: A
authors.lastname: Rodgers
authors.forename: David
authors.initials: D
authors.lastname: Mormeneo
authors.forename: Jaclyn S
authors.initials: JS
authors.lastname: Long
authors.forename: Antonio
authors.initials: A
authors.lastname: Delgado
authors.forename: Nigel J
authors.initials: NJ
authors.lastname: Pyne
authors.forename: Susan
authors.initials: S
authors.lastname: Pyne
mesh_terms: D000818:Animals; D015153:Blotting, Western; D016466:CHO Cells; D002460:Cell Line; D045744:Cell Line, Tumor; D006224:Cricetinae; D003412:Cricetulus; D004247:DNA / Q000096:biosynthesis; D053595:Embryonic Stem Cells / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism; D004789:Enzyme Activation / Q000187:drug effects; D015870:Gene Expression; D006801:Humans; D008246:Lysophospholipids / Q000494:pharmacology*; D051379:Mice; D019950:Mitogen-Activated Protein Kinase 1 / Q000378:metabolism*; D048052:Mitogen-Activated Protein Kinase 3 / Q000378:metabolism*; D010982:Platelet-Derived Growth Factor / Q000494:pharmacology; D011493:Protein Kinase C / Q000378:metabolism; D016392:Proto-Oncogene Proteins pp60(c-src) / Q000378:metabolism; D049349:Receptors, Lysosphingolipid / Q000235:genetics / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013110:Sphingosine / Q000031:analogs & derivatives* / Q000494:pharmacology
chemical_list: D008246:Lysophospholipids; D010982:Platelet-Derived Growth Factor; D049349:Receptors, Lysosphingolipid; C060506:sphingosine 1-phosphate; D004247:DNA; D016392:Proto-Oncogene Proteins pp60(c-src); D011493:Protein Kinase C; D019950:Mitogen-Activated Protein Kinase 1; D048052:Mitogen-Activated Protein Kinase 3; D013110:Sphingosine