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PubMed · 11030651

Localized Rac activation dynamics visualized in living cells.

V S Kraynov·C Chamberlain·G M Bokoch·M A Schwartz·S Slabaugh·K M Hahn
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Abstract

Signaling proteins are thought to be tightly regulated spatially and temporally in order to generate specific and localized effects. For Rac and other small guanosine triphosphatases, binding to guanosine triphosphate leads to interaction with downstream targets and regulates subcellular localization. A method called FLAIR (fluorescence activation indicator for Rho proteins) was developed to quantify the spatio-temporal dynamics of the Rac1 nucleotide state in living cells. FLAIR revealed precise spatial control of growth factor-induced Rac activation, in membrane ruffles and in a gradient of activation at the leading edge of motile cells. FLAIR exemplifies a generally applicable approach for examining spatio-temporal control of protein activity.

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3T3 CellsActinsAnimalsBiosensing TechniquesBloodCell MembraneCell MovementCell NucleusCell PolarityEnzyme ActivationFluorescenceGuanosine TriphosphateMiceNuclear EnvelopePlatelet-Derived Growth FactorRecombinant Fusion ProteinsSpectrometry, Fluorescencerac1 GTP-Binding ProteinJournal ArticleResearch Support, Non-U.S. Gov'tResearch Support, U.S. Gov't, P.H.S.

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V S Kraynov, C Chamberlain, G M Bokoch, M A Schwartz, S Slabaugh, K M Hahn. 2000-10-13. Localized Rac activation dynamics visualized in living cells.. https://doi.org/10.1126/science.290.5490.333

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