Subcellular localization was carried out using 35S:pSKYAtSBT1.1-YFP-and 35S:pSKYAtPSK4-YFP-expressing roots. The roots were stained with propidium iodide and examined with a laser scanning confocal microscope. Confocal microscopy was performed using a Nikon C1si confocal scanning system attached to a 90i microscope (http://www.nikoninstruments.com). The emission signals for YFP and propidium iodide were acquired using sequential scanning mode to eliminate emission signal bleed-through. The 488 line of the argon laser and 515/30 emission filters were used for acquisition of YFP images. The propidium iodide images of root cells were acquired using the 561 argon laser and 590/50 emission filter.