Platelet-derived growth factor-BB modulates membrane mobility of beta1 integrins.
Platelet-derived growth factor (PDGF)-BB elicits a migratory response including reorganization of the actin cytoskeleton in different cell types. Here we have investigated the effects of PDGF-BB stimulation on beta(1) integrin containing focal adhesions in human diploid fibroblasts adhered to collagen type I. Stimulation with PDGF-BB dissociated focal adhesions and relocated beta(1) integrins from focal adhesions to the periphery of the cells. These changes were rapid and transient in character. Relocation of beta(1) integrins was prevented by inhibitors of phosphoinositide-3-kinase and protein kinase C. PDGF-BB stimulated fibroblasts exhibited an increased diffusion coefficient of cell surface beta(1) integrins as determined by fluorescence recovery of photobleaching. The cell surface expression of beta(1) integrins was not changed after stimulation with PDGF-BB. Our data suggest that PDGF-BB increases the dynamic properties of cell-surface beta(1) integrins, which most likely are important for the migratory response elicited by PDGF-BB.
Ahlén
Karina
K
Department of Medical Biochemistry and Microbiology, University of Uppsala, Biomedical Center, Box 582, SE-751 23 Uppsala, Sweden.
Ring
Patrik
P
Tomasini-Johansson
Bianca
B
Holmqvist
Kristina
K
Magnusson
Karl-Eric
KE
Rubin
Kristofer
K
D000077214:Becaplermin; D002448:Cell Adhesion / Q000187:drug effects / Q000502:physiology; D002462:Cell Membrane / Q000187:drug effects / Q000378:metabolism* / Q000648:ultrastructure*; D002478:Cells, Cultured; D018914:Cells, Immobilized / Q000187:drug effects / Q000502:physiology; D024042:Collagen Type I / Q000378:metabolism*; D003599:Cytoskeleton / Q000187:drug effects / Q000378:metabolism; D005347:Fibroblasts / Q000166:cytology* / Q000187:drug effects / Q000378:metabolism*; D036681:Fluorescence Recovery After Photobleaching / Q000379:methods; D006801:Humans; D019012:Integrin beta1 / Q000378:metabolism* / Q000648:ultrastructure; D008560:Membrane Fluidity; D010982:Platelet-Derived Growth Factor / Q000378:metabolism* / Q000494:pharmacology; D021381:Protein Transport / Q000502:physiology*; D020574:Proto-Oncogene Proteins c-sis
D024042:Collagen Type I; D019012:Integrin beta1; D010982:Platelet-Derived Growth Factor; D020574:Proto-Oncogene Proteins c-sis; D000077214:Becaplermin