title: Activation of endogenous Cdc42 visualized in living cells.
abstract: Signaling proteins are tightly regulated spatially and temporally to perform multiple functions. For Cdc42 and other guanosine triphosphatases, the subcellular location of activation is a critical determinant of cell behavior. However, current approaches are limited in their ability to examine the dynamics of Cdc42 activity in living cells. We report the development of a biosensor capable of visualizing the changing activation of endogenous, unlabeled Cdc42 in living cells. With the use of a dye that reports protein interactions, the biosensor revealed localized activation in the trans-Golgi apparatus, microtubule-dependent Cdc42 activation at the cell periphery, and activation kinetics precisely coordinated with cell extension and retraction.
authors.affiliation: Department of Pharmacology, University of North Carolina School of Medicine, Chapel Hill, NC 27599-7365, USA.
authors.forename: Perihan
authors.initials: P
authors.lastname: Nalbant
authors.forename: Louis
authors.initials: L
authors.lastname: Hodgson
authors.forename: Vadim
authors.initials: V
authors.lastname: Kraynov
authors.forename: Alexei
authors.initials: A
authors.lastname: Toutchkine
authors.forename: Klaus M
authors.initials: KM
authors.lastname: Hahn
mesh_terms: D000199:Actins / Q000378:metabolism; D000465:Algorithms; D000818:Animals; D015374:Biosensing Techniques; D002448:Cell Adhesion; D002460:Cell Line; D002462:Cell Membrane / Q000378:metabolism*; D016764:Cell Polarity; D022081:Cell Surface Extensions / Q000378:metabolism / Q000648:ultrastructure; D042783:Endothelial Cells / Q000378:metabolism / Q000648:ultrastructure; D005347:Fibroblasts; D005453:Fluorescence; D005456:Fluorescent Dyes / Q000737:chemistry / Q000378:metabolism; D049452:Green Fluorescent Proteins; D006801:Humans; D008164:Luminescent Proteins; D051379:Mice; D008870:Microtubules / Q000378:metabolism; D018375:Neutrophil Activation; D009504:Neutrophils / Q000378:metabolism*; D011506:Proteins / Q000737:chemistry / Q000378:metabolism; D011554:Pseudopodia / Q000378:metabolism; D011744:Pyrimidinones / Q000378:metabolism; D012680:Sensitivity and Specificity; D051316:Wiskott-Aldrich Syndrome Protein; D020764:cdc42 GTP-Binding Protein / Q000378:metabolism*; D020741:rho GTP-Binding Proteins / Q000378:metabolism; D021601:trans-Golgi Network / Q000378:metabolism* / Q000648:ultrastructure
chemical_list: D000199:Actins; D005456:Fluorescent Dyes; D008164:Luminescent Proteins; D011506:Proteins; D011744:Pyrimidinones; C495767:WAS protein, human; C495768:Was protein, mouse; D051316:Wiskott-Aldrich Syndrome Protein; D049452:Green Fluorescent Proteins; C003954:merocyanine dye; C503256:RHOQ protein, human; C503260:Rhoq protein, mouse; D020764:cdc42 GTP-Binding Protein; D020741:rho GTP-Binding Proteins