Research Paper Volume 8, Issue 4 pp 777—795

Figure 8. HSF-1 is required for induced thermotolerance and full activation of heat shock response and mitochondrial unfolded protein response. While hsf-1 mutant worms show equivalent 37°C heat stress survival compared to WT worms (A), hsf-1 mutants failed to exhibit induced thermotolerance under heat stress after exposure to a mild 35°C heat stress for 2 hours (B-F). hsf-1 mutants are able to increase Phsp-16.2::GFP reporter activity in response to heat stress, but the magnitude of increase is markedly less than WT (G). Similarly, hsf-1 mutants show decreased induction of the Phsp-6::GFP mitoUPR reporter in response to oxidative stress compared to WT worms (G). Once activated, the duration of the HSR, as measured by Phsp-16.2::GFP reporter activity, is reduced in hsf-1 worms compared to WT (H). Similarly, the duration of the mitoUPR in hsf-1 worms is also decreased compared to WT worms after induction with 4 mM PQ (I). Error bars indicate SEM. *p<0.05, **p<0.01, ***p<0.001.