Supplementary Figure 3: Enhanced GSH biosynthesis confers resistance to oxidative stress.

(a, b) Cells were serum-starved for 20–24 h in the presence or absence of 1 μM GSK690693, followed by treatment with 1 mM H₂O₂ for 6 h. Cell death was assessed by 7-AAD staining followed by FACS (data are from one experiment that was independently repeated two times with similar results (Supplementary Table 1)). (c) Total glutathione levels in cells serum-starved for 20–24 h in the presence or absence of 50 μM BSO (n = 3 biologically independent replicates (Supplementary Table 1)). (d–f) Cells were serum-starved for 20–24 h in the presence or absence of 1 μM GSK690693 or 50 μM BSO, followed by treatment with 500 μM H₂O₂ for 4 h. Cells were immunoblotted for the indicated proteins (data is representative of three independent experiments). All error bars represent s.e.m. ^∗∗P < 0.01, ^∗∗∗P < 0.001 by a two-sided Student’s t-test. Unprocessed original scans of blots are shown in Supplementary Fig. 6.