FIGURE 6:

TORC1-mediated activation of Art1 is sufficient to down-regulate the inactive Can1(E184Q) and Can1(87-ELK-89>AAA) mutants. (A) Hypothetical model for the mechanism of Art1-mediated down-regulation of Can1(E184Q) following Gap1-mediated Arg uptake. (B) Strains (with gap1Δ can1Δ mutations) expressing Can1(E184Q) and the gap1Δ can1Δ bul1/2Δ strain expressing GFP-fused wild-type or mutant Can1 (as indicated) were grown on Gal Pro. Glu was added for 1.5 h and then Am for 3 h, before imaging. The PM-to-intracellular-GFP fluorescence intensity ratios (as in Figure 1B) are plotted for the main conditions (n = 60 cells). Quantifications for other control strains are shown in Supplemental Figure S4A. (C) The same strains were grown on Gal Pro, Glu was added for 0.5 h and then Am for 20 min. Protein extracts were probed as in Figure 1C. (D) Strains expressing Can1-GFP or the indicated mutants were grown in Gal Pro. Glu was added for 1.5 h before imaging as in Figure 1A. See also Supplemental Figure S4B. (E) Strains expressing Can1-GFP or the mutant carrying Ala substitutions of residues 87–89 were examined as in Figure 5C. See also Supplemental Figure S4D.