title: Endogenous activation patterns of Cdc42 GTPase within Drosophila embryos.
abstract: Knowing when and where a given protein is activated within intact animals assists in elucidating its in vivo function. With the use of a genetically encoded A-probe (activation bioprobe), we revealed that Cdc42 guanosine triphosphatase (GTPase) remains inactive within Drosophila embryos during the first two-thirds of embryogenesis. Within the central nervous system where Cdc42 activity first becomes up-regulated, individual neurons display patterns restricted to specific subcellular compartments. At both organismal and cellular levels, Cdc42's endogenous activation patterns in the wild type allow predictions of where loss-of-function phenotypes will emerge in cdc42/cdc42 mutants. Genetic tests support the importance of suppressing endogenous Cdc42 activities until needed. Thus, bioprobe-assisted analysis uncovers how ubiquitously expressed signaling proteins control cellular events through continual regulation of their activities within animals.
authors.affiliation: Department of Biology and Miami Institute of Molecular Imaging and Computation, University of Miami, Coral Gables, FL 33146, USA.
authors.forename: Daichi
authors.initials: D
authors.lastname: Kamiyama
authors.forename: Akira
authors.initials: A
authors.lastname: Chiba
mesh_terms: D000818:Animals; D001369:Axons / Q000648:ultrastructure; D002490:Central Nervous System / Q000196:embryology / Q000201:enzymology; D003712:Dendrites / Q000648:ultrastructure; D004330:Drosophila / Q000196:embryology* / Q000201:enzymology / Q000235:genetics; D029721:Drosophila Proteins / Q000235:genetics / Q000378:metabolism*; D004625:Embryo, Nonmammalian / Q000201:enzymology*; D047108:Embryonic Development; D004789:Enzyme Activation; D031541:Fluorescence Resonance Energy Transfer; D015336:Molecular Probe Techniques; D009046:Motor Neurons / Q000166:cytology / Q000201:enzymology*; D009154:Mutation; D038081:Organogenesis; D010641:Phenotype; D020764:cdc42 GTP-Binding Protein / Q000235:genetics / Q000378:metabolism*
chemical_list: D029721:Drosophila Proteins; D020764:cdc42 GTP-Binding Protein