Evidence that Armadillo transduces wingless by mediating nuclear export or cytosolic activation of Pangolin.
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.
Chan
Siu-Kwong
SK
Department of Genetics, Howard Hughes Medical Institute, Columbia University, College of Physicians and Surgeons, New York, NY 10032, USA.
Struhl
Gary
G
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
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