title: Cross-talk between fMLP and vitronectin receptors triggered by urokinase receptor-derived SRSRY peptide.
abstract: The urokinase-type plasminogen activator receptor (uPAR) sustains cell migration through its capacity to promote pericellular proteolysis, regulate integrin function, and mediate chemotactic signaling in response to urokinase. We have characterized the early signaling events triggered by the Ser-Arg-Ser-Arg-Tyr (SRSRY) chemotactic uPAR sequence. Cell exposure to SRSRY peptide promotes directional migration on vitronectin-coated filters, regardless of uPAR expression, in a specific and dose-dependent manner, with maximal effect at a concentration level as low as 10 nm. A similar concentration profile is observed in a quantitative analysis of SRSRY-dependent cytoskeletal rearrangements, mostly consisting of filamentous structures localized in a single cell region. SRSRY analogues with alanine substitutions fail to drive F-actin formation and cell migration, indicating a critical role for each amino acid residue. As with ligand-dependent uPAR signaling, SRSRY stimulates protein kinase C activity and results in ERK1/2 phosphorylation. The involvement of the high affinity N-formyl-Met-Leu-Phe receptor (FPR) in this process is indicated by the finding that 100 nm N-formyl-Met-Leu-Phe inhibits binding of D2D3 to the cell surface, as well as SRSRY-stimulated cell migration and F-actin polarization. Moreover, cell exposure to SRSRY promotes FPR-dependent vitronectin release and increased uPAR.alphavbeta5 vitronectin receptor physical association, indicating that alphavbeta5 activity is regulated by the SRSRY uPAR sequence via FPR. Finally, we provide evidence that alphavbeta5 is required for SRSRY-dependent ERK1/2 phosphorylation, whereas it is not required for protein kinase C activation. The data indicate that the ability of uPAR to stimulate cell migration and cytoskeletal rearrangements is retained by the SRSRY peptide alone and that it is supported by cross-talk between FPR and alphavbeta5.
authors.affiliation: Department of Experimental Oncology, National Cancer Institute, 80131 Naples, Italy.
authors.forename: Lucia
authors.initials: L
authors.lastname: Gargiulo
authors.forename: Immacolata
authors.initials: I
authors.lastname: Longanesi-Cattani
authors.forename: Katia
authors.initials: K
authors.lastname: Bifulco
authors.forename: Paola
authors.initials: P
authors.lastname: Franco
authors.forename: Rosanna
authors.initials: R
authors.lastname: Raiola
authors.forename: Pietro
authors.initials: P
authors.lastname: Campiglia
authors.forename: Paolo
authors.initials: P
authors.lastname: Grieco
authors.forename: Gianfranco
authors.initials: G
authors.lastname: Peluso
authors.forename: M Patrizia
authors.initials: MP
authors.lastname: Stoppelli
authors.forename: Maria V
authors.initials: MV
authors.lastname: Carriero
mesh_terms: D000199:Actins / Q000737:chemistry / Q000378:metabolism; D000409:Alanine / Q000737:chemistry; D000730:Androstadienes / Q000494:pharmacology; D015153:Blotting, Western; D002448:Cell Adhesion; D002460:Cell Line; D002465:Cell Movement; D002633:Chemotaxis; D002867:Chromones / Q000494:pharmacology; D003599:Cytoskeleton / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D005419:Flavonoids / Q000494:pharmacology; D006801:Humans; D047468:Immunoprecipitation; D039564:Integrin alphaV / Q000378:metabolism; D039302:Integrin alphaVbeta3 / Q000737:chemistry*; D039663:Integrin beta4 / Q000378:metabolism; D019950:Mitogen-Activated Protein Kinase 1 / Q000378:metabolism; D048052:Mitogen-Activated Protein Kinase 3 / Q000378:metabolism; D009025:Morpholines / Q000494:pharmacology; D009240:N-Formylmethionine Leucyl-Phenylalanine / Q000378:metabolism; D009281:Naphthalenes / Q000494:pharmacology; D010455:Peptides / Q000737:chemistry; D010766:Phosphorylation; D011485:Protein Binding; D011493:Protein Kinase C / Q000378:metabolism; D011956:Receptors, Cell Surface / Q000378:metabolism*; D044042:Receptors, Formyl Peptide / Q000737:chemistry*; D055293:Receptors, Urokinase Plasminogen Activator; D011994:Recombinant Proteins / Q000737:chemistry; D015398:Signal Transduction; D013696:Temperature; D013997:Time Factors; D019096:Vitronectin / Q000737:chemistry; D000077191:Wortmannin
chemical_list: D000199:Actins; D000730:Androstadienes; D002867:Chromones; D005419:Flavonoids; D039564:Integrin alphaV; D039302:Integrin alphaVbeta3; D039663:Integrin beta4; D009025:Morpholines; D009281:Naphthalenes; C524898:PLAUR protein, human; D010455:Peptides; D011956:Receptors, Cell Surface; D044042:Receptors, Formyl Peptide; D055293:Receptors, Urokinase Plasminogen Activator; D011994:Recombinant Proteins; D019096:Vitronectin; C085911:2-(4-morpholinyl)-8-phenyl-4H-1-benzopyran-4-one; D009240:N-Formylmethionine Leucyl-Phenylalanine; D011493:Protein Kinase C; D019950:Mitogen-Activated Protein Kinase 1; D048052:Mitogen-Activated Protein Kinase 3; C058819:calphostin C; D000409:Alanine; C093973:2-(2-amino-3-methoxyphenyl)-4H-1-benzopyran-4-one; D000077191:Wortmannin