Gap junction formation between normal and reaggregated endoderm cells ofXenopus laevis neurulae.

摘要: Using freeze-fracture electron microscopy and fluorescent dye injection we have analysed the contacts between cells of deeper endoderm taken from neurulae ofXenopus laevis. Endodermal in situ large 1.5 μm diameter gap junctions composed 8 nm P-face particles corresponding E-face pits. Beside junctions, particle aggregates typical desmosomal plaques are present but there no tight junctions. The dissociation into single involves profound structural alterations surface membrane including complete disappearance junctional structures among them reaggregation leads to restoration IMP (Intra Membrane Particle) pattern and, after ca. 30 min, establishment functional pathways allowing for intercellular transfer dye. Concomitantly reappear. observation that endodermal which go beyond cell themselves is discussed as an adaptation plasma changing environmental conditions.