Dishevelled (Dvl-2) activates canonical Wnt signalling in the absence of cytoplasmic puncta

J Cell Sci. 2005 Nov 15;118(Pt 22):5279-89. doi: 10.1242/jcs.02647. Epub 2005 Nov 1.

Abstract

Dishevelled family proteins are multidomain intracellular transducers of Wnt signals. Ectopically expressed mammalian Dishevelled 2 (Dvl-2) activates downstream signalling and localises to cytoplasmic puncta. It has been suggested that these Dvl-2-containing structures correspond to intracellular vesicles and may be involved in the Wnt signal transduction process. We report that cytoplasmic puncta are primarily formed in cells expressing Dvl-2 at high levels. Lower levels of expression can activate signalling without forming puncta. The structures do not localise with markers of the early or late endocytic pathway and time-lapse analysis demonstrates that Dvl-2 puncta move in a random fashion over short distances but do not originate from the plasma membrane. Based on our findings, we propose that Dvl-2 puncta are protein aggregates that are not required for signalling.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adaptor Proteins, Signal Transducing
  • Animals
  • Antigens, CD / metabolism
  • Biomarkers / analysis
  • Cricetinae
  • Cytoplasm / metabolism*
  • Dishevelled Proteins
  • Dogs
  • Endocytosis
  • Endoplasmic Reticulum / metabolism
  • Humans
  • Membrane Proteins / metabolism
  • Phosphoproteins / chemistry
  • Phosphoproteins / genetics
  • Phosphoproteins / metabolism*
  • Platelet Membrane Glycoproteins / metabolism
  • Protein Binding
  • Protein Structure, Tertiary
  • Protein Transport
  • Signal Transduction* / drug effects
  • Tetraspanin 30
  • Time Factors
  • Transfection
  • Vesicular Transport Proteins
  • Wnt Proteins / metabolism*

Substances

  • Adaptor Proteins, Signal Transducing
  • Antigens, CD
  • Biomarkers
  • CD63 protein, human
  • DVL2 protein, human
  • Dishevelled Proteins
  • Membrane Proteins
  • Phosphoproteins
  • Platelet Membrane Glycoproteins
  • Tetraspanin 30
  • Vesicular Transport Proteins
  • Wnt Proteins
  • early endosome antigen 1