Structural Localization of Some Phosphatases in the Golgi Region of Cultivated Cells

Abstract

1. Localization of some phosphatase activities was investigated in the cells cultivated in the multipurpose culture chambers developed by Rose.
2. The activity of thiamine pyrophosphatase was specifically confined to the surface of the phase-gray flecks in the Golgi region. The reaction products encrusted the phase-gray flecks and formed what looked like a tubule with chromophilic walls and a chromophobic lumen, which was similar to a Golgi body demonstrated by metallic impregnation in vertebrate somatic cells.
3. Based on theevidences obtained in the study, it was justified that the phase-gray flecks were the true representatives of the Golgi apparatus in the living cultivated cells and supposedly correspond to the double membrane systems of the Golgi complex observed under the electron microscope.
4. The activity of the acid phosphatase was also found to be associated with the phase-gray flecks, but not with the phase-white vacuoles in the Golgi region which were presumably considered to be lysosomes or secretory droplets.
5. In many preparations showing thiamine pyrophosphatase and acid phosphatase activities, while deposits of the reaction products were found in a very small quantity on the phase-gray flecks in the more central porition of the Golgi region, they were concentrated in a greater quantity on the more peripherally located flecks in the same region. No significant staining was obtained in the test for alkaline phosphatase.