Role of Calcium in the Control of Cytoplasmic Streaming in Permeabilized Nitella Cell

The most plausible factor responsible for controlling the Cytoplasmic Streaming is the Ca++ concentration in the Cytoplasm. Many reports have indicated that various kinds of movements in Eukaryotic cells are regulated by Ca++. It has also been found that red and far red light affect Ca++ movement across the cell membrane (Dreyer and Weisenseel, 1979; Hale and Roux, 1980). In Nitellainternodal Cell Cytoplasmic Streaming is stopped more rapidly in the presence of Ca++when the cells were irradiated with far-red light and the effect of the light was completely removed by EGTA (Ethylene Glycol-bis, N-N-tetra acetic acid). These facts may be interpreted as showing that Calcium accumulates in the Cytoplasm during irradiation and that an increase in Ca++ Concentration in the Cytoplasm inhibits Cytoplasmic Streaming