Figure 4.

Reactive oxygen species‐mediated activation of the oxidative stress response is independent of synaptic transmission. (A) The ROS generator paraquat induces expression of the Pgst‐4:: GFP reporter independent of synaptic transmission. Images show GFP fluorescence of Pgst‐4::GFP reporter animals. Left panel: Wild‐type or synaptic mutant Pgst‐4:: GFP reporter strains (unc‐26(e205), snt‐1(md290)) were treated with water or 100 mm paraquat on day 1 and imaged 8 h later. Right panel: Bar graphs show quantification of fluorescent intensity [A.U.] for wild‐type or synaptic mutants. Fluorescent intensity arbitrary units [A.U.] (y‐axis) for water‐ and paraquat‐treated samples is indicated for each strain. (B) Paraquat induces transcription of sod genes in wild‐type (N2) and synaptic mutant animals. Eight hours after treating day 1 adult wild‐type or mutant animals with water or 100 mm paraquat, RNA was harvested. mRNA levels of sod genes were evaluated by qRT‐PCR and plotted as fold induction (PQ/water) (y‐axis) for each sod gene. (C) Fluoxetine represses expression of the Pgst‐4:: GFP. Images show GFP fluorescence of Pgst‐4:: GFP reporter animals treated with increasing concentrations of Fluoxetine alone, or in combination with 50 μm Mianserin, on day 1 of adulthood. Images were captured 24 h after treatment. (D) Quantification of (C) Fluoxetine‐induced repression of Pgst‐4:: GFP. Fluorescent intensity [A.U.] (y‐axis) is plotted as a function of Fluoxetine concentration [μm] (x‐axis). All error bars show SEM of 3–6 independent experiments. For detailed statistics, see Table S6 (Supporting information). *P<0.05, **P<0.01, ***P<0.001, n.s., not significant P>0.05.