Measurement of Activites of Flippase and Endocytosis on a Plasma Membrane of CHO Cells by Processing the Fluorescence Microscopic Images.

Image processing technique is applied to measurements of activities of phosphatidylserine flippase and endocytosis on a plasma membrane of CHO cells. The fluorescent phosphatidylserine probes (C6- NBD-PS) translocated to inner layer of the plasma membranes aer distributed in the cytoplasmic membranes. Intensity of the fluoescence within the cytoplasmic area is analyzed quantitatively by use of the NIH image. Endocytosis of lucifer yellow molecules are analyzed by the same method after the cytoplamic area is determined by comparing the phase contrast image of the cell. The present technique is available for intact cells cultured on a dish and makes possible to measure the actvities of each cell.