title: Sphingosine 1-phosphate induces filopodia formation through S1PR2 activation of ERM proteins.
abstract: Previously we demonstrated that the sphingolipids ceramide and S1P (sphingosine 1-phosphate) regulate phosphorylation of the ERM (ezrin/radixin/moesin) family of cytoskeletal proteins [Canals, Jenkins, Roddy, Hernande-Corbacho, Obeid and Hannun (2010) J. Biol. Chem. 285, 32476-3285]. In the present article, we show that exogenously applied or endogenously generated S1P (in a sphingosine kinase-dependent manner) results in significant increases in phosphorylation of ERM proteins as well as filopodia formation. Using phosphomimetic and non-phosphorylatable ezrin mutants, we show that the S1P-induced cytoskeletal protrusions are dependent on ERM phosphorylation. Employing various pharmacological S1PR (S1P receptor) agonists and antagonists, along with siRNA (small interfering RNA) techniques and genetic knockout approaches, we identify the S1PR2 as the specific and necessary receptor to induce phosphorylation of ERM proteins and subsequent filopodia formation. Taken together, the results demonstrate a novel mechanism by which S1P regulates cellular architecture that requires S1PR2 and subsequent phosphorylation of ERM proteins.
authors.affiliation: Departments of Molecular and Cellular Biology and Pathobiology, Medical University of South Carolina, Charleston, SC 29425, USA.
authors.forename: K Alexa Orr
authors.initials: KA
authors.lastname: Gandy
authors.forename: Daniel
authors.initials: D
authors.lastname: Canals
authors.forename: Mohamad
authors.initials: M
authors.lastname: Adada
authors.forename: Masayuki
authors.initials: M
authors.lastname: Wada
authors.forename: Patrick
authors.initials: P
authors.lastname: Roddy
authors.forename: Ashley J
authors.initials: AJ
authors.lastname: Snider
authors.forename: Yusuf A
authors.initials: YA
authors.lastname: Hannun
authors.forename: Lina M
authors.initials: LM
authors.lastname: Obeid
mesh_terms: D000818:Animals; D001483:Base Sequence; D045744:Cell Line, Tumor; D002465:Cell Movement / Q000502:physiology; D002478:Cells, Cultured; D003598:Cytoskeletal Proteins / Q000235:genetics / Q000378:metabolism*; D006367:HeLa Cells; D006801:Humans; D008246:Lysophospholipids / Q000378:metabolism* / Q000494:pharmacology; D051379:Mice; D018345:Mice, Knockout; D050505:Mutant Proteins / Q000235:genetics / Q000378:metabolism; D009361:Neoplasm Invasiveness / Q000503:physiopathology; D010766:Phosphorylation; D011554:Pseudopodia / Q000187:drug effects / Q000378:metabolism*; D034741:RNA, Small Interfering / Q000235:genetics; D049349:Receptors, Lysosphingolipid / Q000819:agonists / Q000037:antagonists & inhibitors / Q000172:deficiency / Q000235:genetics / Q000378:metabolism*; D013110:Sphingosine / Q000031:analogs & derivatives* / Q000378:metabolism / Q000494:pharmacology; D000081025:Sphingosine-1-Phosphate Receptors; D000099149:Ezrin
chemical_list: D003598:Cytoskeletal Proteins; D008246:Lysophospholipids; D050505:Mutant Proteins; D034741:RNA, Small Interfering; D049349:Receptors, Lysosphingolipid; D013110:Sphingosine; D000081025:Sphingosine-1-Phosphate Receptors; D000099149:Ezrin; C477522:S1PR2 protein, human; C533955:sphingosine-1-phosphate receptor-2, mouse; C060506:sphingosine 1-phosphate