Myristoylated Naked2 antagonizes Wnt-beta-catenin activity by degrading Dishevelled-1 at the plasma membrane

J Biol Chem. 2010 Apr 30;285(18):13561-8. doi: 10.1074/jbc.M109.075945. Epub 2010 Feb 20.


In Drosophila, naked cuticle is an inducible antagonist of the Wnt-beta-catenin pathway, likely acting at the level of Dishevelled (Dsh/Dvl), an essential component of this pathway. The mechanism by which naked cuticle and its two vertebrate orthologs, Naked1 (NKD1) and Naked2 (NKD2), inhibit Dvl function is unknown. NKD2 is myristoylated, a co-translational modification that leads to its plasma membrane localization. In contrast, myristoylation-deficient G2A NKD2 is cytoplasmic. Herein we show that the ability of Nkd2/NKD2 to antagonize Wnt-beta-catenin activity during zebrafish embryonic development and in mammalian HEK293 cells is myristoylation-dependent. NKD2 and Dvl-1 interact and co-localize at the lateral membrane of polarized epithelial cells. In reciprocal overexpression and siRNA knockdown experiments, NKD2 and Dvl-1 destabilize each other via enhanced polyubiquitylation; this effect is also dependent upon Naked2 myristoylation. Cell fractionation and ubiquitylation assays indicate that endogenous NKD2 interacts with a slower migrating, ubiquitylated form of Dvl-1 in plasma membrane fractions. These results provide a mechanism by which NKD2 antagonizes Wnt signaling: myristoylated NKD2 interacts with Dvl-1 at the plasma membrane, and this interaction leads to their mutual ubiquitin-mediated proteasomal degradation.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adaptor Proteins, Signal Transducing / genetics
  • Adaptor Proteins, Signal Transducing / metabolism*
  • Animals
  • Caco-2 Cells
  • Calcium-Binding Proteins
  • Carrier Proteins / genetics
  • Carrier Proteins / metabolism*
  • Cell Membrane / genetics
  • Cell Membrane / metabolism*
  • Cell Polarity / physiology
  • Dishevelled Proteins
  • Dogs
  • Drosophila
  • Drosophila Proteins
  • Epithelial Cells / metabolism*
  • Humans
  • Myristic Acid / metabolism*
  • Phosphoproteins / genetics
  • Phosphoproteins / metabolism*
  • Proteasome Endopeptidase Complex / genetics
  • Proteasome Endopeptidase Complex / metabolism
  • Protein Modification, Translational / physiology*
  • Signal Transduction / physiology
  • Ubiquitination / physiology
  • Wnt Proteins / genetics
  • Wnt Proteins / metabolism*
  • beta Catenin / genetics
  • beta Catenin / metabolism*


  • Adaptor Proteins, Signal Transducing
  • Calcium-Binding Proteins
  • Carrier Proteins
  • DVL1 protein, human
  • Dishevelled Proteins
  • Drosophila Proteins
  • NKD1 protein, human
  • NKD2 protein, human
  • Phosphoproteins
  • Wnt Proteins
  • beta Catenin
  • dsh protein, Drosophila
  • Myristic Acid
  • Proteasome Endopeptidase Complex