Fig. 8. Vps20p and Vta1p are required for multivesicular body sorting and LY accumulation in the vacuole. The two MVB reporter proteins, Fth1-GFP-Ub (left) and Sna3-GFP (centre) were localised in wild-type (SF838-9D), vps20 (SF838-9Dvpl10) and vta1 (PLY3046) cells. For visualisation of Fth1-GFP-Ub, cells were grown in 100 µM of the iron chelator BPS for 6 hours prior to microscopy. Cells were resuspended in 1% sodium azide, 1% sodium fluoride, 100 mM Tris pH 8.0 prior to microscopy. Endocytosis of LY (right) was measured by incubating cells in media containing LY for 60 minutes at 30°C, washing and viewing the cells by DIC and fluorescence microscopy. Bar, 5 µm.