DIFFERENTIAL PERTURBATIONS IN THE MORPHOGENESIS OF ANTERIOR STRUCTURES INDUCED BY OVEREXPRESSION OF TRUNCATED XB-CADHERIN AND N-CADHERIN INXENOPUS EMBRYOS
S. Dufour et al., DIFFERENTIAL PERTURBATIONS IN THE MORPHOGENESIS OF ANTERIOR STRUCTURES INDUCED BY OVEREXPRESSION OF TRUNCATED XB-CADHERIN AND N-CADHERIN INXENOPUS EMBRYOS, The Journal of cell biology, 127(2), 1994, pp. 521-535
Cadherins, a family of Ca-dependent adhesion molecules, have been prop
osed to act as regulators of morphogenetic processes and to be major e
ffecters in the maintenance of tissue integrity. In this study, we hav
e compared the effects of the expression of two truncated cadherins du
ring early neurogenesis in Xenopus laevis. mRNA encoding deleted forms
of XB- and N-cadherin lacking most of the extracellular domain were i
njected into the four animal dorsal blastomeres of 32-cell stage Xenop
us embryos. These truncated cadherins altered the cohesion of cells de
rived from the injected blastomeres and induced morphogenetic defects
in the anterior neural tissue to which they chiefly contributed. Trunc
ated XB-cadherin was more efficient than N-cadherin in inducing these
perturbations. Moreover, the coexpression of both truncated cadherins
had additive perturbation effects on neural development. The two trunc
ated cadherins can interact with the three known catenins, but with di
stinct affinities. These results suggest that the adhesive signal medi
ated by cadherins can be perturbed by overexpressing their cytoplasmic
domains by competing with different affinity with catenins and/or a c
ommon anchor structure. Therefore, the correct regulation of cadherin
function through the cytoplasmic domain appears to be a crucial step i
n the formation of the neural tissue.