Figure 4

GCN2-dependent effect upon Trp depletion is linked to aromatic amino acid biosynthesis. (A) Simplified schematic of aromatic amino acid anabolism indicating where excess amino acids inhibit biosynthesis according to reference [11]. The crucial step is the feedback inhibition of the first step (red lines). (B) Growth curve of gcn2 Δ with depletion of Trp, Tyr and Phe showing growth recovery in complete media versus Trp depleted media. (C) Heatmap of the wild type and gcn2 Δ strains depleted of all three aromatic amino acids. Red arrow indicates tRNA^Trp and black arrows indicate tRNA^Phe and tRNA^Tyr. (D) Histogram of the relative charging level before and 60 min after triple amino acid depletion for the gcn2 Δ strain.