The appearance of carbohydrate-rich material in the developing Golgi apparatus of amoebae

The silver proteinate reaction was used to stain carbohydrate-rich substances in normal Amoeba proteus and in the developing Golgi apparatus of renucleated amoebae. Normal cells contained stained material, which probably is glycoprotein, in the cell surface, cisternae at the concave pole of the Golgi apparatus, and cytoplasmic vesicles and vacuoles. Previous radioautographic studies had shown tht glycosylation occurs in the Golgi apparatus, and that material in the Golgi apparatus is precursor to the cell surface. Amoebae were enucleated for 5 d, which results in a decline of the Golgi apparatus, the disappearance of the glycoprotein-containing cisternae preceding that of the rest of the organelle. A new nucleus was then transplanted into the enucleate amoebae, bringing about the regeneration of the Golgi apparatus. small curved cisternae that appeared 30 min after renucleation lacked staining with silver proteinate. By 1 h after renucleation, however, the content of cisternae toward the concave poles of Golgi bodies stained with silver proteinate. The Golgi apparatus in cells fixed 6 h and 1 d after operation resembled that of normal amoebae in both morphology and staining pattern. The results suggest that the developing Golgi apparatus acquired the capacity to participate in assembly of cell-surface material within 1 h after renucleation. This occurred before development of the normal enzymic activity of the Golgi apparatus was completed.