Chemotaxis of MDCK-F cells toward fibroblast growth factor-2 depends on transient receptor potential canonical channel 1.
Movement toward the source of a chemoattractant gradient is a basic cellular property in health and disease. Enhanced migration during metastasis involves deregulated growth factor signaling. Growth factor stimulation and cell migration converge both on the important second messenger Ca(2+). To date, the molecular identification of Ca(2+) entry pathways activated by growth factors during chemotaxis is still an open issue. We investigated the involvement of the nonselective Ca(2+) channel TRPC1 (transient receptor potential canonical 1) in FGF-2 guided chemotaxis by means of time-lapse video microscopy and by functional Ca(2+) measurements. To specifically address TRPC1 function in transformed MDCK cells we altered the expression levels by siRNA or overexpression. We report that TRPC1 channels are required for the orientation of transformed MDCK cells in FGF-2 gradients because TRPC1 knockdown or pharmacological blockade prevented chemotaxis. Stimulation with FGF-2 triggered an immediate Ca(2+) influx via TRPC1 channels that depended on phospholipase C and phosphatidylinositol 3-kinase signaling. Impeding this Ca(2+) influx abolished chemotaxis toward FGF-2. This functional connection correlated with clustering of FGF receptors and TRPC1 channels as was observed by immunolabeling. These findings show the important interplay between growth factor signaling and Ca(2+) influx in chemotaxis.
Institute of Physiology II, University of Münster, Robert-Koch-Str. 27b, 48149, Münster, Germany. afabian@uni-muenster.de
Anke
A
Fabian
Thomas
T
Fortmann
Etmar
E
Bulk
Valerie C
VC
Bomben
Harald
H
Sontheimer
Albrecht
A
Schwab
D000730:Androstadienes / Q000494:pharmacology; D000818:Animals; D002118:Calcium / Q000378:metabolism; D020013:Calcium Signaling; D002460:Cell Line; D002633:Chemotaxis / Q000502:physiology*; D004285:Dogs; D004963:Estrenes / Q000494:pharmacology; D016222:Fibroblast Growth Factor 2 / Q000378:metabolism*; D006801:Humans; D036341:Intercellular Signaling Peptides and Proteins; D019950:Mitogen-Activated Protein Kinase 1 / Q000378:metabolism; D048052:Mitogen-Activated Protein Kinase 3 / Q000378:metabolism; D010455:Peptides / Q000494:pharmacology; D011760:Pyrrolidinones / Q000494:pharmacology; D051496:Receptor, Fibroblast Growth Factor, Type 1 / Q000378:metabolism; D013111:Spider Venoms / Q000494:pharmacology; D050052:TRPC Cation Channels / Q000502:physiology*; D000077191:Wortmannin
D000730:Androstadienes; D004963:Estrenes; D036341:Intercellular Signaling Peptides and Proteins; C411249:MTx4 protein, Grammostola spatulata; D010455:Peptides; D011760:Pyrrolidinones; D013111:Spider Venoms; D050052:TRPC Cation Channels; C096351:transient receptor potential cation channel, subfamily C, member 1; D016222:Fibroblast Growth Factor 2; C060229:1-(6-((3-methoxyestra-1,3,5(10)-trien-17-yl)amino)hexyl)-1H-pyrrole-2,5-dione; D051496:Receptor, Fibroblast Growth Factor, Type 1; D019950:Mitogen-Activated Protein Kinase 1; D048052:Mitogen-Activated Protein Kinase 3; D002118:Calcium; D000077191:Wortmannin