Figure 1. SAGA is epistatic to the TORC1 and TORC2 pathways in the regulation of differentiation in response to nutrient availability.

• A–D
  Expression of ste11 ⁺ (A, C) and mei2 ⁺ (B, D) using quantitative RT–PCR of RNA extracted from cells grown either in nutrient rich medium (dark gray) or shifted for 4 h to starvation medium (light gray). Cells of the following genotypes were analyzed: wild‐type isogenic controls (WT), gcn5Δ, tsc1Δ, gcn5Δ tsc1Δ, tsc2Δ, gcn5Δ tsc2Δ, rhb1‐DA4—a constitutively active (CA) rhb1 mutant 34, gcn5Δ rhb1‐DA4, tor2‐L1310P—a CA tor2 mutant 33, gcn5Δ tor2‐L1310P, tor1Δ, gcn5Δ tor1Δ, gad8Δ, and gcn5Δ gad8Δ. act1 ⁺ served as a control for normalization across samples. Values from a WT strain grown in rich medium were set at 1 to allow comparisons across culture conditions and mutant strains. Each column represents the mean value of 4 (A, B) or 3 (C, D) independent experiments, overlaid with individual data points and error bars showing the standard error of the mean (SEM). Statistical significance was determined by two‐way ANOVA followed by Bonferroni's multiple comparison tests (n = 4 for A, B; n = 3 for C, D); *P ≤ 0.01.
• E, F
  Cells were grown to mid‐log phase either in rich medium or shifted for 8 h to starvation medium. Zygotes and tetrads, which correspond to differentiated cells, were counted under a light microscope. Cells of the following genotypes were analyzed: WT isogenic controls, gcn5Δ, tsc1Δ, gcn5Δ tsc1Δ, rhb1‐DA4, gcn5Δ rhb1‐DA4, gad8Δ, and gcn5Δ gad8Δ. Each value represents the mean percentage and SEM of differentiating cells to the total number of cells, averaged from four independent experiments. At least 200 cells from the indicated genotypes were counted in each experiment. White arrowheads indicate zygotes. Scale bar, 10 μm.