The appearance of ganglioside during embryological development of the frog

Embryological stages after fertilization were examined for the appearance of gangliosides. In Rana pipiens, gangliosides were found to appear first at the late gastrula, a stage well before any morphological appearance of a nervous system. Furthermore, at this stage and at a later stage, hatching, only two of the four major gangliosides were detected, namely, monosialoganglioside G_M1 and disialoganglioside G_D1a.