Modulation of mouse neural crest cell motility by N-cadherin and connexin 43 gap junctions

Connexin 43 (Cx43 alpha1) gap junction has been shown to have an essential role in mediating functional coupling of neural crest cells and in modulati ng neural crest cell migration. Here, we showed that N-cadherin and wnt1 ar e required for efficient dye coupling but not for the expression of Cx43 al pha1 gap junctions in neural crest cells. Cell motility was found to be alt ered in the N-cadherin-deficient neural crest cells, but the alterations we re different from that elicited by Cx43 alpha1 deficiency. In contrast, wnt 1-deficient neural crest cells showed no discernible change in cell motilit y. These observations suggest that dye coupling may not be a good measure o f gap junction communication relevant to motility. Alternatively, Cx43 alph a1 may serve a novel function in motility. We observed that p120 catenin (p 120ctn), an Armadillo protein known to modulate cell motility, is colocaliz ed not only with N-cadherin but also with Cx43 alpha1. Moreover, the subcel lular distribution of p120ctn was altered with N-cadherin or Cx43 alpha1 de ficiency. Based on these findings, we propose a model in which Cx43 alpha1 and N-cadherin may modulate neural crest cell motility by engaging in a dyn amic cross-talk with the cell's locomotory apparatus through p120ctn signal ing.