title: Trimeric G protein-dependent frizzled signaling in Drosophila.
abstract: Frizzled (Fz) proteins are serpentine receptors that transduce critical cellular signals during development. Serpentine receptors usually signal to downstream effectors through an associated trimeric G protein complex. However, clear evidence for the role of trimeric G protein complexes for the Fz family of receptors has hitherto been lacking. Here, we show roles for the Galpha(o) subunit (Go) in mediating the two distinct pathways transduced by Fz receptors in Drosophila: the Wnt and planar polarity pathways. Go is required for transduction of both pathways, and epistasis experiments suggest that it is an immediate transducer of Fz. While overexpression effects of the wild-type form are receptor dependent, the activated form (Go-GTP) can signal when the receptor is removed. Thus, Go is likely part of a trimeric G protein complex that directly transduces Fz signals from the membrane to downstream components.
authors.affiliation: Department of Genetics and Development, Center for Neurobiology and Behavior, College of Physicians and Surgeons, Columbia University, 701 West 168 Street, New York, NY 10032, USA.
authors.forename: Vladimir L
authors.initials: VL
authors.lastname: Katanaev
authors.forename: Romina
authors.initials: R
authors.lastname: Ponzielli
authors.forename: Michel
authors.initials: M
authors.lastname: Sémériva
authors.forename: Andrew
authors.initials: A
authors.lastname: Tomlinson
mesh_terms: D000818:Animals; D016764:Cell Polarity / Q000235:genetics / Q000502:physiology; D004330:Drosophila; D029721:Drosophila Proteins / Q000378:metabolism*; D051157:Frizzled Receptors; D019206:GTP-Binding Protein alpha Subunits, Gi-Go / Q000235:genetics / Q000502:physiology*; D049452:Green Fluorescent Proteins / Q000235:genetics; D036341:Intercellular Signaling Peptides and Proteins / Q000378:metabolism; D008565:Membrane Proteins / Q000378:metabolism*; D010641:Phenotype; D011518:Proto-Oncogene Proteins / Q000378:metabolism; D043562:Receptors, G-Protein-Coupled; D015398:Signal Transduction; D014921:Wings, Animal / Q000254:growth & development / Q000378:metabolism; D051153:Wnt Proteins; D051155:Wnt1 Protein
chemical_list: D029721:Drosophila Proteins; D051157:Frizzled Receptors; D036341:Intercellular Signaling Peptides and Proteins; D008565:Membrane Proteins; D011518:Proto-Oncogene Proteins; D043562:Receptors, G-Protein-Coupled; D051153:Wnt Proteins; D051155:Wnt1 Protein; C058784:fz protein, Drosophila; C074622:wg protein, Drosophila; D049452:Green Fluorescent Proteins; D019206:GTP-Binding Protein alpha Subunits, Gi-Go