INHIBITION OF MORPHOGENETIC MOVEMENT DURING XENOPUS GASTRULATION BY INJECTED SULFATASE - IMPLICATIONS FOR ANTEROPOSTERIOR AND DORSOVENTRAL AXIS FORMATION

In order to explore the role of morphogenetic movement in the establis hment of anteroposterior and dorsoventral axes, we sought to identify novel in vivo inhibitors of gastrulation movements in Xenopus laevis. Injection of hydrolytic sulfatase into the blastocoels of gastrula sta ge embryos resulted in severe anteroposterior truncation, without a co rresponding truncation of the dorsoventral axis. Confocal microscopy o f whole embryos revealed that gastrulation movements are severely disr upted by sulfatase; in addition, sulfatase dramatically inhibited chor domesodermal cell elongation and convergent extension movements in pla nar dorsal marginal zone explants. The phenotype of anteroposterior re duction elicited by sulfatase is distinctly different from commonly ge nerated dorsoanterior phenotypes (e.g., ultraviolet irradiation of the vegetal cortex prior to cortical rotation or suramin injection), and the two varieties of phenotype appear to result from inhibition of dis tinct, separable components of the axis-generating machinery. (C) 1997 Academic Press.