Fig 4.

Hac1 and Gcn4 mutually influence their mRNA expression levels. (A) Relative GCN4 mRNA levels of either a haploid or diploid wild-type strain (RH2816 and RH2656) and a haploid or diploid HAC1 deletion strain (RH3351 and RH3412) were determined by qRT-PCR and normalized against H2A. Starting from one main culture with an OD₆₀₀ of ∼0.6 at 30°C, cultures were divided and cultivated for a further 90 min under the indicated conditions. Amino acid starvation was induced by 10 mM 3AT (dark gray bars, +3AT), ER stress conditions were achieved by 1 μg/ml tunicamycin (black bars, +Tm). Experiments were performed from three independent cultures for each strain and condition. The mRNA levels were normalized to the respective untreated (YNB) wild type. Standard deviations are indicated as error bars. (B) HAC1 mRNA levels were analyzed similarly in either a haploid or a diploid wild-type strain (RH2816 and RH2656) and a haploid or a diploid GCN4 deletion strain (RH2676 and RH2658).