Abstract
Cyanidioschyzon merolae has been used as a suitable model system for studies of organelles because the cells have a simple structure: they contain only one nucleus, one mitochondrion, one chloroplast, one microbody, one Golgi apparatus. However, lysosomes have never been identified. We are studying on structures that fluoresced yellow after staining with DAPI because the accumulation of polyphosphate in vacuoles is known in several organisms and DAPI emits a yellow fluorescence when it associates with polyphosphate. There was plurality of these structures in a cell and the number varied among the cells. During cell division, these structures attached to mitochondria and were inherited almost evenly. Quinacrine, which accumulates in acidic organelles, stained the similar structures. Electron microscopy showed the similar structures containing electron-dense material surrounded by monolayer membranes. These results suggest that the structures stained with DAPI are acidic and membrane surrounded organelles. For further identification, we isolated these structures.
