Ultrastructural study of contacts between cells of the dorsal ectoderm and chordamesoderm during gastrulation in Xenopus laevis.

In gastrulae of Xenopus laevis, various morphological types of intercellular approximation occur between the dorsal ectoderm and chordamesoderm. Ruthenium red staining reveals that in some areas the glycocalyces of heterotypic cells appear to come into contact. These observations, in conjunction with the results of previous studies, suggest that cell contacts offer a possible pathway for the transmission of inductive stimuli, and that they may be important in the regionalization of the neuralized ectoderm.