Fig. 6

Phosphorylation of Hsf1 by Sch9 is required for Hsf1 activation upon glucose depletion but is not required for Hsf1 activation upon heat shock. a, b Total protein or total RNA was prepared from glucose-grown, glucose depleted, or heat shocked (42 °C, 15 min) cells as described in Methods section. Analysis of Hsf1 phosphorylation was performed as described in Fig. 5. H4: hyper-phosphorylated Hsf1 species formed upon heat shock. RT–PCR for the genes indicated was performed with total RNA. Actin (ACT1) levels were used as a loading control. Glucose starvation in RT–PCR experiments was 30 min to allow for the expression of a detectable amount of Hsf1-induced transcripts. The Hsf1–H3 species was stable during a 30 min glucose depletion time course (Supplementary Fig. 4c)