title: Sphingosine 1-phosphate activates Erk-1/-2 by transactivating epidermal growth factor receptor in rat-2 cells.
abstract: We investigated a signaling pathway leading to activation of extracellular signal-regulated protein kinase (Erk) 1 and 2 in Rat-2 cells stimulated with sphingosine 1-phosphate (S1P). S1P treatment transiently activated Erk-1/-2 in a dose-dependent manner, and its activation was blocked by pertussis toxin, expression of RasN17, or inhibition of Raf or MEK-1/-2. S1P-induced activation of Erk-1/-2 was also suppressed by the inhibition of epidermal growth factor (EGF) receptor tyrosine kinase with the specific inhibitor AG1478, suggesting that activation of EGF receptor tyrosine kinase was involved in the signaling pathway. S1P-induced Erk-1/-2 activation was enhanced up to 2-fold by inhibiting protein kinase C (PKC) with GF109203X, and PKC inhibition in the absence of S1P treatment also activated Erk-1/-2. The stimulatory effects of Erk-1/-2 activation by PKC inhibition was blocked by treating cells with AG1478, suggesting the involvement of PKC in the regulation of EGF receptor tyrosine kinase activation that leads to Erk-1/-2 activation. Together, these results suggest that S1P activates the EGF receptor through a PKC-dependent pathway that links Ras signaling to the activation of Erk-1/-2 in Rat-2 cells.
authors.affiliation: Department of Life Science, Kwangju Institute of Science and Technology, Korea.
authors.forename: J H
authors.initials: JH
authors.lastname: Kim
authors.forename: J H
authors.initials: JH
authors.lastname: Kim
authors.forename: W K
authors.initials: WK
authors.lastname: Song
authors.forename: J H
authors.initials: JH
authors.lastname: Kim
authors.forename: J S
authors.initials: JS
authors.lastname: Chun
mesh_terms: D016475:3T3 Cells; D000818:Animals; D002460:Cell Line; D004305:Dose-Response Relationship, Drug; D004789:Enzyme Activation; D004791:Enzyme Inhibitors / Q000494:pharmacology; D066246:ErbB Receptors / Q000235:genetics / Q000378:metabolism*; D006367:HeLa Cells; D049691:History, Medieval; D006801:Humans; D007211:Indoles / Q000494:pharmacology; D008246:Lysophospholipids; D048369:MAP Kinase Kinase 1; D048370:MAP Kinase Kinase 2; D008301:Maleimides / Q000494:pharmacology; D051379:Mice; D019950:Mitogen-Activated Protein Kinase 1 / Q000378:metabolism*; D048052:Mitogen-Activated Protein Kinase 3; D020929:Mitogen-Activated Protein Kinase Kinases / Q000037:antagonists & inhibitors; D020928:Mitogen-Activated Protein Kinases / Q000378:metabolism*; D037342:Pertussis Toxin; D011493:Protein Kinase C / Q000037:antagonists & inhibitors; D017346:Protein Serine-Threonine Kinases / Q000037:antagonists & inhibitors; D011505:Protein-Tyrosine Kinases / Q000037:antagonists & inhibitors; D019908:Proto-Oncogene Proteins c-raf / Q000037:antagonists & inhibitors; D011799:Quinazolines; D051381:Rats; D015398:Signal Transduction; D013110:Sphingosine / Q000031:analogs & derivatives* / Q000378:metabolism*; D013997:Time Factors; D015533:Transcriptional Activation; D020032:Tyrphostins / Q000494:pharmacology; D010566:Virulence Factors, Bordetella / Q000494:pharmacology
chemical_list: D004791:Enzyme Inhibitors; D007211:Indoles; D008246:Lysophospholipids; D008301:Maleimides; D011799:Quinazolines; D020032:Tyrphostins; D010566:Virulence Factors, Bordetella; C101044:RTKI cpd; C060506:sphingosine 1-phosphate; D037342:Pertussis Toxin; C482128:MAP2K2 protein, human; D066246:ErbB Receptors; D011505:Protein-Tyrosine Kinases; D017346:Protein Serine-Threonine Kinases; D019908:Proto-Oncogene Proteins c-raf; D011493:Protein Kinase C; D019950:Mitogen-Activated Protein Kinase 1; D048052:Mitogen-Activated Protein Kinase 3; D020928:Mitogen-Activated Protein Kinases; D048369:MAP Kinase Kinase 1; D048370:MAP Kinase Kinase 2; C482125:MAP2K1 protein, human; C482127:Map2k1 protein, mouse; D020929:Mitogen-Activated Protein Kinase Kinases; C070515:bisindolylmaleimide I; D013110:Sphingosine