During gastrulation, embryonic cells acquire new positions and identities through coordinated cell movements that are driven by signalling cues and by cell-cell adhesion. On , Fong et al. show that in zebrafish ectoderm, the T-box gene Tbx2b acts through a Wnt receptor to regulate cell adhesion and,consequently, the cell movements underlying neural plate formation. They show that Tbx2b-deficient embryos express less cadherin than wild-type embryos do and that isolated cells adhere poorly to each other. In chimaeric embryos, Tbx2b-depleted cells fail to move normally during gastrulation and so are excluded from the developing neural plate. Finally, the researchers use this exclusion phenotype to show that Tbx2b acts through Fz7, a Wnt receptor. They suggest that this developmental link between T-box genes and Wnt signalling may be evolutionarily conserved, and that the regulation of cell-cell adhesion might be a general function of T-box proteins.
