A PTK7/Ror2 Co-Receptor Complex Affects Xenopus Neural Crest Migration

PLoS One. 2015 Dec 17;10(12):e0145169. doi: 10.1371/journal.pone.0145169. eCollection 2015.

Abstract

Neural crest cells are a highly migratory pluripotent cell population that generates a wide array of different cell types and failure in their migration can result in severe birth defects and malformation syndromes. Neural crest migration is controlled by various means including chemotaxis, repellent guidance cues and cell-cell interaction. Non-canonical Wnt PCP (planar cell polarity) signaling has previously been shown to control cell-contact mediated neural crest cell guidance. PTK7 (protein tyrosine kinase 7) is a transmembrane pseudokinase and a known regulator of Wnt/PCP signaling, which is expressed in Xenopus neural crest cells and required for their migration. PTK7 functions as a Wnt co-receptor; however, it remains unclear by which means PTK7 affects neural crest migration. Expressing fluorescently labeled proteins in Xenopus neural crest cells we find that PTK7 co-localizes with the Ror2 Wnt-receptor. Further, co-immunoprecipitation experiments demonstrate that PTK7 interacts with Ror2. The PTK7/Ror2 interaction is likely relevant for neural crest migration, because Ror2 expression can rescue the PTK7 loss of function migration defect. Live cell imaging of explanted neural crest cells shows that PTK7 loss of function affects the formation of cell protrusions as well as cell motility. Co-expression of Ror2 can rescue these defects. In vivo analysis demonstrates that a kinase dead Ror2 mutant cannot rescue PTK7 loss of function. Thus, our data suggest that Ror2 can substitute for PTK7 and that the signaling function of its kinase domain is required for this effect.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Cell Movement*
  • Neural Crest / cytology
  • Neural Crest / embryology
  • Neural Crest / metabolism*
  • Protein Binding
  • Receptor Protein-Tyrosine Kinases / genetics
  • Receptor Protein-Tyrosine Kinases / metabolism*
  • Receptor Tyrosine Kinase-like Orphan Receptors / genetics
  • Receptor Tyrosine Kinase-like Orphan Receptors / metabolism*
  • Wnt Signaling Pathway
  • Xenopus
  • Xenopus Proteins / genetics
  • Xenopus Proteins / metabolism*

Substances

  • Xenopus Proteins
  • PTK7 protein, Xenopus
  • Receptor Protein-Tyrosine Kinases
  • Receptor Tyrosine Kinase-like Orphan Receptors
  • Ror2 protein, Xenopus

Grants and funding

This work was funded by Deutsche Forschungsgemeinschaft, grant number BO 1978/ 4-2. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.