Fig. 2: Cytosolic NADP redox homoeostasis is robustly maintained.

a Epifluorescence microscopy images of yeast cells expressing NAPstar3, showing cpT-Sapphire and mCherry fluorescence as well as brightfield microscopy. Representative image; images were obtained from three independent yeast cultures. b–g Response of PeredoxDS, NAPstar3 and NAPstarC probes, expressed in the cytosol of wild-type and Δzwf1 yeast cells, to the addition of exogenous H₂O₂ at the indicated concentrations (n = 3 experimental repeats in which H₂O₂ responses were monitored in cells derived from independent cultures. Identical experimental settings were used for all panels allowing for direct comparison of TS/mC between datasets. h Epifluorescence microscopy images showing cpT-Sapphire and mCherry fluorescence of NAPstar3b expressed in the cytosol of HeLa cells. Representative image; images were obtained from four separate HeLa cell cultures. i Response to NAPstar3b (n = 148 individual cells for the starved condition and n = 151 individual cells for the glucose condition, monitored in both cases in the course of four experimental replicates) and HyPer7 (n = 144 individual cells for the starved condition and n = 154 individual cells for the glucose condition, monitored in both cases in the course of n = 3 experimental replicates) probes, expressed in the cytosol of HeLa cells cultured in a perfusion chamber, to the perfusion of buffers with stepwise increases in H₂O₂ concentration. Within each experimental replicate, the response was determined as the mean of the individual cell responses. Data are presented as the mean of experimental replicates with error bars representing the standard deviation between experimental replicates.