Fig. 6. Characterization of Met30p stability. The HA-tagged full-length Met30 and Met30ΔF proteins were expressed from a GAL1 promoter by growing the cells for 2 h in 2% galactose. Glucose (2%) and cycloheximide (50 μg/ml) were added and the cells were allowed to grow for the indicated times in the presence or absence of 1 mM l–methionine. Upper panel: the stability of both HA-Met30 and HA–Met30ΔF was monitored in W303-1A wild-type cells. Lower panel: the stability of HA-Met30 was monitored in the SCF mutants skp1-11 and cdc53-1 by shifting the cells to 37°C before the addition of galactose as well as in met4Δ mutant cells.