title: Localized Rac activation dynamics visualized in living cells.
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.
authors.affiliation: Department of Cell Biology, The Scripps Research Institute, La Jolla, CA 92037, USA.
authors.forename: V S
authors.initials: VS
authors.lastname: Kraynov
authors.forename: C
authors.initials: C
authors.lastname: Chamberlain
authors.forename: G M
authors.initials: GM
authors.lastname: Bokoch
authors.forename: M A
authors.initials: MA
authors.lastname: Schwartz
authors.forename: S
authors.initials: S
authors.lastname: Slabaugh
authors.forename: K M
authors.initials: KM
authors.lastname: Hahn
mesh_terms: D016475:3T3 Cells; D000199:Actins / Q000378:metabolism; D000818:Animals; D015374:Biosensing Techniques; D001769:Blood; D002462:Cell Membrane / Q000201:enzymology* / Q000502:physiology / Q000648:ultrastructure; D002465:Cell Movement; D002467:Cell Nucleus / Q000201:enzymology*; D016764:Cell Polarity; D004789:Enzyme Activation; D005453:Fluorescence; D006160:Guanosine Triphosphate / Q000378:metabolism*; D051379:Mice; D009685:Nuclear Envelope / Q000201:enzymology; D010982:Platelet-Derived Growth Factor / Q000494:pharmacology; D011993:Recombinant Fusion Proteins / Q000378:metabolism; D013050:Spectrometry, Fluorescence; D020830:rac1 GTP-Binding Protein / Q000378:metabolism*
chemical_list: D000199:Actins; D010982:Platelet-Derived Growth Factor; D011993:Recombinant Fusion Proteins; D006160:Guanosine Triphosphate; D020830:rac1 GTP-Binding Protein