By exchanging cytoplasmic proteins with exogenously added proteins, antibodies or cytosol that has been prepared from cells at distinct stages of the cell cycle or differentiation, or from disease states, we can modulate the intracellular environment and reconstitute various physiological phenomena in semi-intact cells. The semi-intact cell method was originally established by Dr. Simons’ group to study polarized vesicular trafficking in Madin-Darby canine kidney (MDCK) cells (Ikonen et al., 1995). We have refined the method by coupling it with GFP-visualization techniques and have established many types of assay for cell cycledependent changes in organelle morphology and membrane trafficking. Using our analytical system, we can manipulate intracellular conditions and.
