Fig. (3) Mutants affected in genes encoding ETF and ETF-dH display decreased intracellular oxidation upon heat shock. Cells of the parental strain (BY4741) and of mutants affected in AIM45(aim45), YGR207c/CIR1 (cir1) and YOR356w/CIR2 (cir2) were loaded with the oxidant-sensitive fluorescent probe 2’,7’-dichlorodihydrofluorescein diacetate and exposed to 50ºC for 30min. Fluorescence was recorded in each cell lysate and compared to loaded cells without exposition to 50ºC. *P < 0.05 and **P < 0.01 when compared with strain BY4741 with the same time incubation..