title: Evidence that Armadillo transduces wingless by mediating nuclear export or cytosolic activation of Pangolin.
abstract: Secreted proteins of the Wnt family have profound organizing roles during animal development and are transduced via the activities of the Frizzled (Fz) class of transmembrane receptors and the TCF/LEF/Pangolin class of transcription factors. beta-catenins, including Drosophila Armadillo (Arm), link activation of Fz at the cell surface to transcriptional regulation by TCF in the nucleus. The consensus view is that Wnt signaling induces beta-catenin to enter the nucleus and combine with TCF to form a transcription factor complex in which TCF binds DNA and the C-terminal domain of beta-catenin activates transcription. Here, we present findings, which challenge this view and suggest instead that beta-catenin may transduce Wnt signals by exporting TCF from the nucleus or activating it in the cytoplasm.
authors.affiliation: Department of Genetics, Howard Hughes Medical Institute, Columbia University, College of Physicians and Surgeons, New York, NY 10032, USA.
authors.forename: Siu-Kwong
authors.initials: SK
authors.lastname: Chan
authors.forename: Gary
authors.initials: G
authors.lastname: Struhl
mesh_terms: D021581:Active Transport, Cell Nucleus; D000818:Animals; D001135:Armadillos / Q000502:physiology*; D003598:Cytoskeletal Proteins; D003600:Cytosol / Q000378:metabolism*; D004330:Drosophila; D029721:Drosophila Proteins / Q000235:genetics*; D005047:Etoposide / Q000378:metabolism; D005786:Gene Expression Regulation; D019476:Insect Proteins / Q000378:metabolism*; D009687:Nuclear Proteins; D017434:Protein Structure, Tertiary; D011518:Proto-Oncogene Proteins / Q000235:genetics*; D012097:Repressor Proteins; D015398:Signal Transduction; D015534:Trans-Activators; D014157:Transcription Factors / Q000378:metabolism*; D051155:Wnt1 Protein; D051176:beta Catenin
chemical_list: D003598:Cytoskeletal Proteins; D029721:Drosophila Proteins; D019476:Insect Proteins; D009687:Nuclear Proteins; D011518:Proto-Oncogene Proteins; D012097:Repressor Proteins; D015534:Trans-Activators; D014157:Transcription Factors; D051155:Wnt1 Protein; D051176:beta Catenin; C115159:pan protein, Drosophila; C094236:pendulin; C074622:wg protein, Drosophila; D005047:Etoposide