A morphological study on regulation of hyaline bleb formation in early embryonic cells of Cynops pyrrhogaster

Summary Presumptive ectodermal cells isolated from the animal pole region of Cynops pyrrhogaster embryos showed active formation of hyaline blebs after the eleventh cleavage. The role of the submembranous cortical layer (SCL) in hyaline bleb formation was investigated in relation to the number of cleavages. Rhodamine-phalloidin staining and transmission electron-microscopy showed structural changes in the SCL after the eleventh cleavage. Partial breakdown of the SCL by electric pulses and deformation of the SCL by treatment with cycloheximide and nocodazole induced hyaline bleb formation before the eleventh cleavage. These results suggest that the SCL plays an important role in hyaline bleb formation after the eleventh cleavage.