Abstract
We have been analyzing the mechanism of protein targeting to the vacuoloes using tobacco BY-2 cells as model. We have already shown that tobacco BY-2 cells at log phase of growth have two distinct vacuolar targeting machinery. To extend this knowledge, we are currently analyzing vacolar targeting in stationary-grown BY-2 cells. Transformed cells expressing either secretory GFP or cytochrome b5-RFP fusion accumulated the florescence of these proteins in the vacuoles of stationary-grown cells. Because starvation is one of the reasons to stop cell growth, we analyzed if sugar removal from the medium caused the relocation these proteins to the vacuole. Cyt b5-RFP, but not secretory GFP, was trasnsported to the vacuole under this starvation condition. We are currently analyzing this starvation-induced vacuolar relocation mechanism. In this symposium, recent data on the transduction of starvation signal to cause the relocation will be discussed.
