Unipolar membrane association of Dishevelled mediates Frizzled planar cell polarity signaling.
Drosophila epithelia acquire a planar cell polarity (PCP) orthogonal to their apical-basal axes. Frizzled (Fz) is the receptor for the PCP signal, and Dishevelled (Dsh) transduces the signal. Here, I demonstrate that unipolar relocalization of Dsh to the membrane is required to mediate PCP, but not Wingless (Wg) signaling. Dsh membrane localization reflects the activation of Fz/PCP signaling, revealing that the initially symmetric signal evolves to one that displays unipolar asymmetry, specifying the cells' ultimate polarity. This transition from symmetric to asymmetric Dsh localization requires Dsh function, and reflects an amplification process that generates a steep intracellular activity gradient necessary to determine PCP.
Axelrod
J D
JD
Department of Pathology, Stanford University School of Medicine, Stanford, California 94305-5324, USA. jaxelrod@cmgm.stanford.edu
D048868:Adaptor Proteins, Signal Transducing; D000818:Animals; D015153:Blotting, Western; D002462:Cell Membrane / Q000378:metabolism / Q000648:ultrastructure; D016764:Cell Polarity / Q000235:genetics / Q000502:physiology*; D000072261:Dishevelled Proteins; D004330:Drosophila / Q000166:cytology / Q000378:metabolism*; D029721:Drosophila Proteins; D051157:Frizzled Receptors; D049452:Green Fluorescent Proteins; D008164:Luminescent Proteins / Q000378:metabolism; D008565:Membrane Proteins / Q000235:genetics / Q000378:metabolism*; D008856:Microscopy, Fluorescence; D010750:Phosphoproteins / Q000235:genetics / Q000378:metabolism; D011518:Proto-Oncogene Proteins / Q000235:genetics / Q000378:metabolism; D011956:Receptors, Cell Surface / Q000235:genetics / Q000378:metabolism*; D043562:Receptors, G-Protein-Coupled; D012097:Repressor Proteins / Q000235:genetics / Q000378:metabolism; D015398:Signal Transduction; D051155:Wnt1 Protein
D048868:Adaptor Proteins, Signal Transducing; D000072261:Dishevelled Proteins; D029721:Drosophila Proteins; D051157:Frizzled Receptors; D008164:Luminescent Proteins; D008565:Membrane Proteins; D010750:Phosphoproteins; D011518:Proto-Oncogene Proteins; D011956:Receptors, Cell Surface; D043562:Receptors, G-Protein-Coupled; D012097:Repressor Proteins; D051155:Wnt1 Protein; C000606588:dsh protein, Drosophila; C058784:fz protein, Drosophila; C074622:wg protein, Drosophila; D049452:Green Fluorescent Proteins