The Apical Determinants aPKC and dPatj Regulate Frizzled-dependent Planar Cell Polarity in the Drosophila Eye

Cell. 2005 May 20;121(4):621-631. doi: 10.1016/j.cell.2005.03.014.

Abstract

Planar cell polarity (PCP) is a common feature of many vertebrate and invertebrate epithelia and is perpendicular to their apical/basal (A/B) polarity axis. While apical localization of PCP determinants such as Frizzled (Fz1) is critical for their function, the link between A/B polarity and PCP is poorly understood. Here, we describe a direct molecular link between A/B determinants and Fz1-mediated PCP establishment in the Drosophila eye. We demonstrate that dPatj binds the cytoplasmic tail of Fz1 and propose that it recruits aPKC, which in turn phosphorylates and inhibits Fz1. Accordingly, components of the aPKC complex and dPatj produce PCP defects in the eye. We also show that during PCP signaling, aPKC and dPatj are downregulated, while Bazooka is upregulated, suggesting an antagonistic effect of Bazooka on dPatj/aPKC. We propose a model whereby the dPatj/aPKC complex regulates PCP by inhibiting Fz1 in cells where it should not be active.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Animals
  • Binding Sites / physiology
  • Cell Membrane / metabolism
  • Cell Polarity / genetics*
  • Down-Regulation / physiology
  • Drosophila Proteins / genetics
  • Drosophila Proteins / metabolism*
  • Drosophila melanogaster / embryology*
  • Drosophila melanogaster / metabolism
  • Drosophila melanogaster / ultrastructure
  • Epithelial Cells / metabolism*
  • Epithelial Cells / ultrastructure
  • Eye / embryology*
  • Eye / metabolism
  • Eye / ultrastructure
  • Eye Proteins / genetics
  • Eye Proteins / metabolism*
  • Frizzled Receptors
  • Intracellular Signaling Peptides and Proteins / metabolism
  • Macromolecular Substances
  • Membrane Proteins / genetics
  • Membrane Proteins / metabolism*
  • Phosphorylation
  • Photoreceptor Cells, Invertebrate / embryology
  • Photoreceptor Cells, Invertebrate / metabolism
  • Protein Binding / physiology
  • Protein Kinase C / metabolism*
  • Receptors, G-Protein-Coupled
  • Tight Junction Proteins
  • Up-Regulation / physiology

Substances

  • Drosophila Proteins
  • Eye Proteins
  • Frizzled Receptors
  • Intracellular Signaling Peptides and Proteins
  • Macromolecular Substances
  • Membrane Proteins
  • PATJ protein, Drosophila
  • PATJ protein, human
  • Receptors, G-Protein-Coupled
  • Tight Junction Proteins
  • baz protein, Drosophila
  • crb protein, Drosophila
  • fz protein, Drosophila
  • PKC-3 protein
  • Protein Kinase C