Wnt-5a induces Dishevelled phosphorylation and dopaminergic differentiation via a CK1-dependent mechanism

J Cell Sci. 2007 Feb 15;120(Pt 4):586-95. doi: 10.1242/jcs.03368. Epub 2007 Jan 23.

Abstract

Previously, we have shown that Wnt-5a strongly regulates dopaminergic neuron differentiation by inducing phosphorylation of Dishevelled (Dvl). Here, we identify additional components of the Wnt-5a-Dvl pathway in dopaminergic cells. Using in vitro gain-of-function and loss-of-function approaches, we reveal that casein kinase 1 (CK1) delta and CK1epsilon are crucial for Dvl phosphorylation by non-canonical Wnts. We show that in response to Wnt-5a, CK1epsilon binds Dvl and is subsequently phosphorylated. Moreover, in response to Wnt-5a or CK1epsilon, the distribution of Dvl changed from punctate to an even appearance within the cytoplasm. The opposite effect was induced by a CK1epsilon kinase-dead mutant or by CK1 inhibitors. As expected, Wnt-5a blocked the Wnt-3a-induced activation of beta-catenin. However, both Wnt-3a and Wnt-5a activated Dvl2 by a CK1-dependent mechanism in a cooperative manner. Finally, we show that CK1 kinase activity is necessary for Wnt-5a-induced differentiation of primary dopaminergic precursors. Thus, our data identify CK1 as a component of Wnt-5a-induced signalling machinery that regulates dopaminergic differentiation, and suggest that CK1delta/epsilon-mediated phosphorylation of Dvl is a common step in both canonical and non-canonical Wnt signalling.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adaptor Proteins, Signal Transducing / metabolism*
  • Animals
  • Casein Kinase I / metabolism*
  • Cell Differentiation / drug effects*
  • Cell Line
  • Cells, Cultured
  • Dishevelled Proteins
  • Immunohistochemistry
  • Kinetics
  • Mesencephalon / cytology
  • Mesencephalon / embryology
  • Mice
  • Models, Biological
  • Neurons / cytology
  • Neurons / drug effects*
  • Phosphoproteins / metabolism*
  • Phosphorylation / drug effects
  • Rats
  • Rats, Sprague-Dawley
  • Wnt Proteins / pharmacology*
  • Wnt-5a Protein

Substances

  • Adaptor Proteins, Signal Transducing
  • Dishevelled Proteins
  • Dvl2 protein, mouse
  • Phosphoproteins
  • Wnt Proteins
  • Wnt-5a Protein
  • Wnt5a protein, mouse
  • Casein Kinase I